National Bureau of Standards

Library, M.W. Bldg

APR 8 1965

^ecknical ^iote 304

BIBLIOGRAPHY ON TROPOSPHERIC PROPAGATION

OF RADIO WAVES

WILHELM NUPEN

mm

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards is a principal focal point in the Federal Government for assuring

maximum application of the physical and engineering sciences to the advancement of technology in industry and commerce. Its responsibilities include development and maintenance of the national stand- ards of measurement, and the provisions of means for making measurements consistent with those standards; determination of physical constants and properties of materials; development of methods

for testing materials, mechanisms, and structures, and making such tests as may be necessary, particularly for government agencies; cooperation in the establishment of standard practices for incorporation in codes and specifications; advisory service to government agencies on scientific and technical problems; invention and development of devices to serve special needs of the Government; assistance

to industry, business, and consumers in the development and acceptance of commercial standards and

simplified trade practice recommendations; administration of programs in cooperation with United

States business groups and standards organizations for the development of international standards of

practice; and maintenance of a clearinghouse for the collection and dissemination of scientific, technical, and engineering information. The scope of the Bureau's activities is suggested in the following

listing of its four Institutes and their organizational units. Institute for Basic Standards. Electricity. Metrology. Heat. Radiation Physics. Mechanics. Applied Mathematics. Atomic Physics. Physical Chemistry. Laboratory Astrophysics.* Radio Standards Laboratory: Radio Standards Physics; Radio Standards Engineering.** Office of Standard Ref- erence Data. Institute for Materials Research. Analytical Chemistry. Polymers. Metallurgy. Inorganic Materials. Reactor Radiations. Cryogenics.** Office of Standard Reference Materials.

Central Radio Propagation Laboratory.** Ionosphere Research and Propagation. Troposphere

and Space Telecommunications. Radio Systems. Upper Atmosphere and Space Physics.

Institute for Applied Technology. Textiles and Apparel Technology Center. Building Research.

Industrial Equipment. Information Technology. Performance Test Development. Instrumentation.

Transport Systems. Office of Technical Services. Office of Weights and Measures. Office of Engineering Standards. Office of Industrial Services.

* NBS Group, Joint Institute for Laboratory Astrophysics at the University of Colorado.

* * Located at Boulder, Colorado.
NATIONAL BUREAU OF STANDARDS

Technical Note 304

ISSUED APRIL 1, 1965

BIBLIOGRAPHY ON TROPOSPHERIC PROPAGATION

OF RADIO WAVES

Wilhelm Nupen

Central Radio Propagation Laboratory

National Bureau of Standards

Boulder, Colorado

NBS Technical Notes are designed to supplement the Bureau's regular publications program. They provide a means for making available scientific data that are of transient or limited interest. Technical Notes may be

listed or referred to in the open literature.

For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C., 20402 - Price $2.00
NOTE:

Abstractors /Tropospheric radio wave propagation bibliography

MGA Staff members:

A. A ANDREW ASSUR

R.B RONALD BAKER

C.E.P.B C.E.P. BROOKS

I.L. D IS ADORE L. DORDICK

M.B. G M.B. GAVRISHEFF

D. M. G DOROTHY M. GROPP

P. A. K PAULINE A. KEEHN

E. K ELEMER KISS

H. P. K HARRIS P. KRAMER

D. B. K DOV B. KRIMGOLD

N. N NNDEM E. U, NNDEM

S.N SYLVIA NOWINSKA

W. N WILHELM NUPEN

M. R MALCOLM RIGBY

I.S ISMAIL SAAD

E.Z.S EVELYN Z. SINHA

O. T OTTO TABORSKY

G. T GEZA THURONYI

Others:

H.T.D H.T.Dougherty

R. M ROBERT Mc COLLUM

R.S.Q R.S. QUIROS

BRITISH INSTITUTE OF RADIO ENGINEERS

ELECTRICAL ENGINEERS

N. T. G. NACHRICHTENTECHNISCHE GESELLSCHAFT

WIRELESS ENGINEERS

Library Symbols:

DBS...

DGS .. DLC .. DWB . . DN-HO

. .U.S. National Bureau of Standards, Washington, D.C.

.. U. S. Geological Survey, Washington, D.C.

..Library of Congress, Washington, D.C.

. .U.S. Weather Bureau, Suitland, Maryland

. .U.S. Navy Hydrographic Office, Suitland, Maryland
CONTENTS

INTRODUCTION Page i

SUBJECT OUTLINE iii

GEOGRAPHICAL OUTLINE xxxv

BIBLIOGRAPHY ON TROPOSPHERIC

PROPAGATION OF RADIOWAVES

AUTHOR INDEX 280

SUBJECT INDEX (alphabetized) 290

LIST OF JOURNALS 299

BIBLIOGRAPHY ON TROPOSPHERIC PROPAGATION

OF RADIO WAVES

INTRODUCTION

This is the fifth in a series of bibliographies being prepared by the M&GA staff

of the American Meteorological Society for the Boulder Laboratories of the National

Bureau of Standards. The first four were:

(1) Bibliography on Ionospheric Propagation of Radio Waves (1923-

1960). NBS Technical Note No. 84, Oct. 1960. (1404 items)

(2) Bibliography on Meteoric Radio Wave Propagation. NBS Technical

Note No. 94, May 1961. (368 items)

(3) Bibliography on Auroral Radio Wave Propagation . NBS Technical

Note No. 128, Jan. 1962. (297 items)

(4) Bibliography on Atmospheric Aspects of Radio Astronomy. NBS

Technical Note No. 171, May 1963. (1013 items)

The present bibliography on Tropospheric Propagation of Radio Waves contains

over a thousand abstracts or titles taken from the literature published between 1945

and 1964, incl. , but the bulk of the literature comes after 1955.

The subject matter in this bibliography is confined to the effects of the Earth's

atmosphere on radiofrequency radiation from 10 cps to 100,000 Mc.

Obviously not all of the vast amount of current and past literature on tropospheric

propagation is included in this compilation, yet in spite of this fact, and in spite of

gaps in the coverage of the world's literature in this field, the selection of material has

been quite rigorous.

The following detailed subject outline shows the scope and the many facets of the

material included herein. A geographical and an author index are also included.

We wish to express appreciation for guidance given by the staff of the NBS Boulder

Laboratories, particularly to Mr. Bradford R.Bean, for valuable assistance in determining

the scope and content of this and previous bibliographies on radio propagation. We also

wish to thank Mrs. Doris Nickey for patient labor in typing and correcting the master

copies of these five bibliographies; to Mr. Geza Thuronyi and Elemer Kiss for abstracting

a large number of recent items; to Mrs.Susanne Manovill for preparing the Geographic

Outline; and to other members of the M&GA staff for their contributions.

These bibliographies are available through the U. S. Department of Commerce, Office

of Technical Services, Washington 25, D.C. This publication, NBS Technical Note No.

, is available from the Superintendent of Documents, U.S. Government Printing

Office, Washington 25, D.C.

Any comments, criticisms, corrections, additions, or material for future radio

propagation bibliographies should be addressed to:

Malcolm Rigby, Editor

Meteorological & Geoastrophysical Abstracts

P. O. Box 1736

Washington 13, D.C. - 20013
11

INDEX to the SUBJECT OUTLINE

I. GENERAL WORKS, p. iii - iv

1. Textbooks, Manuals, Monographs, p. iii 2. Scientific reports, Technical re- ports, Committee reports, Project reports, Research programs, p. iii 3. Theses, p. iii

4. Data publications, p. iii 5. General reviews and surveys, p. iv

6. Bibliographies, p. iv

7. Conferences, symposia, p. iv

8. History, p. iv

9. Nomenclature, p. iv

II. THEORIES, FORMULAS, MODELS, p. iv - viii

1. Theories, p. iv - vi

2. Formulas, p. vi - viii

3. Models, p. viii

III. ATMOSPHERIC STRUCTURE AND CHARACTERISTICS, p. viii - xiii

1. Stratification, p. viii - ix

2. Atmospheric factors, p. ix

3. Refractive index, p. ix - x

4. Air masses, p. x - xi

5. Fronts, p. xi

6. Turbulence, p. xi

7. Winds, p. xi

8. Storms, p. xi

9. Clouds, p. xi

10. Atmospheric altitudes (tables in

km, ft, mb), p. xii

11. Miscellaneous, p. xiii

12. Ionosphere, p. xiii

IV. PHYSICO - CHEMICAL FACTORS AND PROCESSES, p. xiii

1. Scattering, p. xiii

2. Reflection, p. xiv

3. Refraction, p. xiv

4. Diffraction, p. xiv

5. Absorption, p. xiv

6. Attenuation, p. xv

7. Scintillation, p. xv

8. Dielectrics, p. xv

9. Surface conductivity, p. xv

10. Ionization, p. xv

11. Miscellaneous, p. xv

V. WAVE CHARACTERISTICS, p. xvi - xxii

1. Frequency bands (EHF.SHF, UHF,

VHF, HF, MF.LF, VLF, ELF, etc. ), p. xvi

2. KMc/s (GC/s), Mc/s, Kc/s,

and Cps, p. xvii - xix

VI. RADIO COMMUNICATION, p. xxii - xxvii

1. Experimental transmission, p. xxii

2. Transmission losses, p. xxii

3. Forecasting conditions for radio

communication, p. xxii - xxiii

4. Effects on radio communication, p. xxiii

3. Wavelength (mm, cm, m, km), p. xix - xx

4. Propagation modes, p. xx - xxi

5. Fading, p. xxi

6. Echoes, p. xxi

7. Miscellaneous waves, p. xxi - xxii

5. Terrestrial effects, p. xxiii • xxiv

6. Miscellaneous, p. xxiv

7. Reception, Field strength, p. xxiv - xxv

8. Radio communication paths, p. xxv

9. Path lengths (Mi, Ft, Km) , p. xxvi - xxvii

VII. INSTRUMENTS, EQUIPMENT, DESIGN CONSIDERATIONS, p. xxvii - xxx

1. Antenna types, p. xxvii 4. System design considerations, p. xxviii

2. Antenna characteristics, p. xxviii 5. Miscellaneous instruments, p. xxviii

3. System reliabilities, p. xxviii

VIII. TECHNIQUES AND METHODS, THEORETICAL AND APPLIED, p. xxx - xxxiv
Ill SUBJECT OUTLINE

I. GENERAL WORKS

1. Textbooks, E-71, 143, 161, 168, 181, 436, 449, 575, 597, 676, 687, 693,

699, 710, 769, 784, 880, 1095

Manuals, E-195, 226

Monographs, E-12, 42, 67, 76, 147, 165, 173, 222, 240, 281, 293, 297,

310, 389, 405, 406, 418, 432, 483, 536, 583, 699, 821, 822,

824, 875, 895, 909, 912, 917, 923, 932, 936, 942, 944, 1059

2. Scientific reports, E-33, 35, 36, 67, 87, 101, 108, 129-132, 145, 200, 255,

261, 264, 369, 385, 437, 480, 501, 641, 788, 813, 823, 851, 869,

888, 987, 998, 1014, 1073

Technical reports, E-34, 93, 99, 113, 122, 140, 146, 151, 152, 177, 194,

195, 197, 215, 269, 272, 298, 337, 343, 360, 397, 418, 531, 580,

622, 638, 659, 667, 737, 789, 798, 800, 819, 821, 822, 835, 337,

879, 882, 929, 963, 964, 1054, 1075, 1083, 1093

Interim reports, E-157, 595

Committee reports, E-49, 51, 87, 124, 303, 586, 648, 728, 756

Project reports

The "Arowa" project, E-595

The Canterbury project, E-145, 228

Research programs, 1043, 1107

Cheyenne Mountain Propagation Program, E-237, 271, 272

Japan's Antarctic Research Expedition, E-571

Arctic radio research, 1066

3. Theses, E-242

Compilations, E-98, 337, 501, 1083

4. Data publications, E-40, 60, 61, 70, 76, 118, 132, 145, 241, 322, 460,

630, 688, 696

Statistical data, E-82, 131, 162, 167, 198, 241, 260, 289, 297, 331,379,

Atlases, E-341, 675 1058

Maps

Air-sea refractive index difference, E-460

Annual temperature, E-341

Ground conductivity/U.S. , E-245, 252, 977

Humidity, E-341

USA, average absolute humidity, E-442

World wide, E-441

Inversion frequency, E-194, 341

Probable service coverage of radio stations, E-1021

Refractive index, E-341, 808, 840

World wide (sea level values), E-611, 696

Radio Refractiv? Index Data Centers, 1104
CurvesBasic propagation loss, E-927

Calculating absorption for different atmospheric layers, E-827

Calculating field strength, E-48, 140, 497, 559, 728, 977

Communication prediction, E-941

Communication system engineers, E-456

Coupling loss/narrow b-sam antennas, E-918

Ground wave propagation, E-303, 432, 737, 1025

Polarization, E-84

Reflection, E-48

Refraction, E-175

Nomograms, E-263, 456

Refractive index, E-79, 122, 123, 196

5. General reviews and surveys, E-33, 45, 68,87, 106, 121, 130, 145, 160,

180, 240, 241, 276, 279, 235, 314, 325, 329, 359, 380,

394, 395, 407, 410, 435, 437, 480, 504, 536, 555, 582,

589, 618, 624, 638, 646, 659, 824, 899, 920, 929, 944,

1061

British works, E-944

Japanese works, E-993

Soviet bloc works, E-883

U.S. works since 1957, E-895

Scattering theories, E-920

Theories/index of refraction, absorption and dispersion, E-972

Theories of radio wave propagation in terrestrial waveguides, E-1024

6. Bibliographies (>50refs.), E-14, 46, 76, 87, 98, 129, 136, 168, 181, 192,

205, 255, 276, 277, 314, 322, '325, 337, 397, 404, 406,

436, 449, 452, 465, 501, 505, 595, 597, 605, 646, 658,

659, 676, 684, 710, 744, 769, 771, 796, 824, 841, 875,

880, 883, 886, 950, 972, 987, 993, 1031, 1073, 1083, 1093

7. Conferences, Symposia, E-169, 193, 227, 306, 407, 421, 452, 465, 526,

570, 646, 728, 875, 919, 1038, 1063, 1098, 1102

Lectures, E-16, 139, 210, 933

Collected works, E-126, 227, 421, 452, 919

8. History, E-181, 671, 866, 893

9. Nomenclature, E-221, 348, 526

II. THEORIES, FORMULAS, MODELS, etc.

1. Theories

Booker and Gordon's/scattering, E-203, 272, 322, 340, 793, 1045

Booker and Walkinshaw's/refraction

Bremmer and van der Pol's/diffraction, E-322

Fresnel - Kirchhoff "s/diffraction, E-308, 311, 328, 405, 1057

Furutsu's/ground wave field intensity, E-270

Gallet and Villars, Weisskopf's heuristic theories, E-416

Green's theorem, E-238

Huygen - Kirchhoff s principle, E-405, 407, 794

Kirchhoff s diffraction, E-955, 1091

Kolmogorov and Obukhov's/turbulence, E-668, 923, 939

Marcuwitz - Schwinger's formatism, E-979

Millington's analysis, E-679
Nukkubgtib's/field strength, E-679

Nyquist's principle, E-864

Obukhov's/turbulent mixing, E-416, 423, 859, 1037

Raleigh's theory, E-190

S.O. Rice's/scatter, E-231

Schwarz's derivative, E-876

Sommerfeld's theory, E-534

Stratton and Wheeler's theory, extended, E-1069

Villars - Weisskopf - Wheelon/turbulent mixing, E-260, 529

Watson's residue series, E-427

Weisskopf - Villar's/scatter, E-322

Weizsacker - Heisenberg's statistical theory/turbulence, E-260

Miscellaneous

Absorption in scattering, E-1028

"Addition theorem", E-849

Airless earth, E-1024

Analysis of signal statistics, E-672

Bending of radio waves around the Earth, E-7

Bilinear refraction - diffraction, E-263

Central limit theorem, E-330, 1048, 1050

Coherent scattering/tropospheric inhomogeneities, E-836

Coherent long distance USW propagation, E-642

Cross distortion, E-764

Diffraction theories, E-286, 308, 311, 322, 328, 405, 418, 491, 534,

717, 727, 899, 955, 956, 1036

Diffusion, E-363, 376, 772, 785, 786

Dipole, E-292

Distribution law/field component fluctuations, E-884

Diversity reception, E-665

Duct, E-240

Electromagnetic wave, E-109, 282, 682

Elevated layers, E-131

Engineering calculation/USW Communication, E-505

Equilibrium theory of turbulence, E-477

Fading properties, E-1050

Field strength, E-270, 358, 459, 679

Review of theories, E-426

Flat earth scattering, E-1029

Ground wave propagation, E-466, 563, 774, 960, 1085

Hybrid ray and wave theory, E-133

Information theory/aspects, E-243, 290

Invariant bedding/electromagnetic wave propagation, E-701

Isotropic mixing, E-529

Knife edge, E-593

Kolmogorov's - Obukhov's turbulence theory, E-668, 923, 939

Layer reflection, E-843

Law of atmospheric stability/radio wave propagation, E-847

Microwave optics, E-788

Modification in air mass by eddy diffusion, E-126

Multiple path hypothesis, E-409

Noise, E-182

Nukkubgtibs/field strength, E-679

Nyquist's principle, E-864

Obstacle gain, E-322

Obukhov's turbulent mixing, E-416, 423, 859, 1037

Propagation theories, E-17, 18, 70, 81, 83, 87, 103, 180, 223, 239, 240,

263, 273, 318, 329, 367, 450, 496, 497, 547, 555, 568,

598, 624, 642-645, 672, 704, 710, 835, 1100
Radio ducts, E-78, 109

Ray theories, E-39, 48, 200, 317, 344, 407, 457, 475, 1085

Reciprocity theorem, E-387

Reflection theories, E-182, 458, 496, 843, 847

Refraction theories, E-7, 31, 86, 91, 139, 140, 166, 242, 254, 322, 384

Scatter theories, E-15, 91, 92, 139, 159, 202, 203, 231, 235, 268, 272,

275, 289, 295, 322, 335, 340, 376, 336, 389, 410, 470,

476, 477, 529, 555, 588, 597, 649, 660, 664, 672, 704,

755, 766, 788, 793, 836, 851, 920, 950, 980, 1028, 1029, 1100

Statistical theories

Atmospheric density fluctuations, E-265

Atmospheric propagation, E-644, 645

Atmospheric reflection, E-445

Atmospheric scattering, E-980

Atmospheric turbulence, E-289, 494, 498, 649, 676

Turbulence, E-126, 260, 289, 376, 416, 423, 477, 494, 498, 529, 531,

649, 668, 672, 676, 682, 758, 923, 939, 966, 1080, 1100

2. Formulas

Brogg's statistical formula, E-950

Booker and Gordon's, E-171, 216, 275

Bremmer's, E-432

Batchelor's/scatter cross section, E-577

Debye's expression/refractive index, E-886

Domb and Pryce's formula, E-43

Einstein - Focker's, E-538

Fresnel's, E-567, 656

Fresnel - Kirchoff's, E-985

Green's functions, E-246, 446

Gordon's/spherical Earth, E-312

Hankel's functions, E-956

Hufford's, E-534

Kirchhoff's approximation, E-373, 520

Laplace's differential operations, E-346

Leontovich and Fok's, E-662

Maxwell's, E-134, 543, 950, 980

Norton's prediction formula/a new regression coefficient, E-941

Poisson's, E-346

Pekeris, Booker and Gordon's integral expressions, E-417

Riccati's differential equation/solution, E-956

Sommerfield's, E-238

Van der Pol's, E-432

Van der Pol and Bremmer's, E-981

Wong's equations/ray curvature, E-1000

Watson's formula/diffraction, E-373

Watson's formula/transformation, E-446

Whittacker's functions, E-446

Miscellaneous

Absorption, E-683

Angle diversity correlation, E-922

Angle of scattering, E-748

Antenna gain loss, E-766, 922

Atmospheric structure, E-942

Attenuation coefficient, E-42

Attenuation function, E-562, 563, 594

Basic jamming situations (9 eqs.

)
Bandwidth estimation, E-1009

Conductivities, E-975

Correlation functions/amplitude-frequency-multipath distortions, E-730

Correlation functions/phase and amplitude, E-652, 654, 943

Correlation functions/transhorizon system design, E-665

Cross noise power, E-767

Cross talk calculation, E-663

Dielectric constants, E-975

Diffraction, E-48, 138, 1055

Diffraction prediction, E-994

Diffraction/surface waves, E-591, 592

Directional transmission, E-3

Eddy diffusion, E-776

Eigen values, E-318, 662

Field strength, E-48, 166, 309, 344, 405, 434, 459, 836, 931

Ground wave field strength, E-30

Ground wave/property definition, E-440

Height gain differential equation/solution, E-892

Intermodulation noise, E-863, 947

Light - shadow zones, E-42

Maximum range of radars, E-50

Narrow beam bandwidth, E-275

Nonspherical Earth, E-312

Percent of time/non-interference of signals, E-658

Radio refractive index, E-164, 177, 595, 975

Radio refractive index, analog computer solution, E-207

Radio wave propagation, E-53, 629, 731, 773

Radio wave refraction, E-155, 868, 976, 1012

Radio wave refraction, prediction, E-970, 994

Relative beam curvature, E-128

Scattering of radio waves, E-496, 506-508

Signal strength/diversity effects, E-832

Signal strength/antenna characteristics, E-1015

Signal strength/fluctuation prediction, E-38

Surface wave problem solution, E-34

System design, E-851, 854

System loss, E-658

System performance, E-854

TV band (300 - 900 Mc/s), E-162

TV distortion/estimation, E-829

Transmission loss, E-403

3 - D ray paths, E-1000

Tropospheric influence/Doppler shift/satellite signals, E-991

USW propagation, E-18

Volume, E-171

Wave phase, E-67, 1077

Waves, E-282
VX11

3. Models

Anisotropically turbulent tropospheric layer, E-788

Atmosphere, E-568, 1038, 1040

A. R.D.C., E-827

Exponential, E-614, 909

Exponential/ray bending, E-853

Fok's, E-899

Horizontally stratified, E-131

Turbulent, E-658

Booker and Gordon's troposphere, E-257

Comparison between Obukhoff et al's and the Booker and Gordon Scatter

model, E-416

Diffracted field, E-625

Fury model, E-378

em propagation, E-979

M - curve, E-656

Modified exponential model/blob cutoff, E-345

Over water propagation, E-313

Phenomenological vector/reflection from ocean, E-357

Radio refractive index, E-615, 693, 698, 704

Radio refractive index/stratospheric, E-614, 1040

Scatter models, E-113, 362, 537, 600, 863

Scatter models/blobs, E-494

Scatter models/six flux, anisotropic, E-363

Scatter models/two flux, anisotropic, E-363

Schematic fading model, E-382

Turbulent element, E-498

Waterman's model, E-1035

III. ATMOSPHERIC STRUCTURE AND CHARACTERISTICS

1. Stratification, E-21, 22, 52, 93, 105, 134, 172, 189, 263, 318, 339, 346,

347, 377, 385, 400, 493, 542, 554, 580, 584, 588, 604,

637, 703, 704, 714, 735, 753, 755. 771, 777, 779, 788,

811, 827, 842, 877, 900, 901, 936, 942, 945, 979, 996,

1040, 1041, 1080

Gravitational stratification, E-953

Thermal stratification, E-823

Water vapor stratification, E-823

"Foliation", E-1037

Horizontal stratification, E-1047

C - region, E-22, 23

Inversions, E-22, 28, 40, 56, 66, 76, 77, 112, 114, 123, 127, 152,

154, 173, 174, 176, 177, 189, 220, 307, 309, 310, 321,

360, 385, 422, 469, 470, 474, 487, 489, 546, 547, 581,

609, 741, 823, 849, 926, 942, 1074

Detection, E-179

Reflecting boundaries, E-24, 25, 53, 72, 206, 220, 393, 425, 445, 458,

541, 755, 901

Layers

Inversion layers, E-41, 229, 489, 525, 546, 566, 724, 849, 904,

921, 1002

Reflective layers, E-909, 910, 922

Lower layers, E-72, 74, 93, 116, 862, 934, 938, 951, 1041

Influence on field strength, E-151, 400
IX Ground layers, E-660, 770, 780. 785-787, 1002

Influence on radio navigation, E-780

Influence on geodetic measurements, E-780

Undulated layers, E-S37, 1026

Turbulent layers, E-542, 852

Moving layers, E-1035

Stable layers, E-542, 846, 900, 936

Small layers, E-S69

Superrefractive layers, E-1C46

Ducts, E-l. 3, 6, 39, 64, 65, 73. 78, 85, 93, 95, 99, 107, 109, 120,

127, 134, 140, 144, 145, 148, 163, 166, 173, 133-185,

195, 204, 208, 228, 261, 278, 334, 339, 365, 372, 385,

414, 446, 547, 581, 609, 621, 656, 708, 726, 741, 776,

806, 821, 860, 861, 869, 962, 979, 1024, 1061, 1067.

1074, 1097

2. Atmospheric factors

Temperature, E-10, 33, 36, 40, 56, 60, 73, 74, 76, 81, 89, 94, 101,

104, 115, 122, 123, 126, 128, 151, 153, 155, 159, 177,

180. 183, 187, 196, 209, 212, 214, 221, 222, 224, 249,

252, 263, 278, 284, 291, 309, 329, 334, 360, 365, 377,

400, 404, 416, 422, 448, 474, 483, 489, 525, 527, 542,

556, 569, 609, 611, 613, 696, 723, 806, 807, 862, 871,

940, 987, 1020, 1037, 1074

Humidity, moisture, water vapor, E-10, 36, 40, 56, 60, 73, 74, 78, 93,

102, 104, 126, 128, 153, 154, 159, 177, 180, 189. 209,

221, 250, 265, 284, 291, 329, 334, 347, 365, 374, 400,

404, 525, 527, 530, 542, 550, 609, 611-613, 637, 696,

703, 723, 770, 806, 846, 862, 871, 916. 921, 940, 942,

987, 1020, 1037, 1074

Water vapor pressure, E-10, 33, 52, 77, 84, 115, 123, 212, 249,

278, 309, 334, 422

Dew point, E-10, 40, 122, 153, 155, 222, 224

Mist, E-940

Fog, E-398, 454, 940

Pressure, E-l, 94, 114, 151. 155, 209, 212, 221, 222, 224, 291, 310,

383, 474, 525, 527, 550. 556, 611, 696, 682, 807

3. Refractive index, E-10, 40, 41, 60, 81, 84, 86, 88, 89, 101, 121, 154. 158,

188, 203, 256, 282, 284, 285, 291, 317, 318, 336, 372,

377, 402, 441, 442, 446, 525, 544, 550, 555, 581, 590,

597, 606, 610, 611, 612, 621, 641, 703, 723, 735, 748,

752, 780, 781, 784, 806-808, 810, 846, 862, 869, 878,

886, 896, 897. 917, 936, 941, 951. 968, 970, 972, 979,

996, 1000, 1012, 1047. 1059, 1074. 1097

Structure, E-285, 383, 460, 484, 497, 613, 661, 693, 696, 778. 808,

881, 931, 944, 971, 1020, 1032, 1084

Profiles, E-105, 131, 184, 185, 194-197, 237, 239, 249, 263, 269, 272,

360, 368, 384, 385, 437, 443, 522, 546, 558, 604, 615,

622, 662, 681, 696, 705, 773, 805, 904, 969, 996, 1024,

1044, 1097

Gradients, E-65, 74, 79, 128, 133, 186, 198, 209, 273, 278, 303, 360,

399, 458, 461, 479, 480. 563, 577, 584, 590, 634, 693.

703, 753, 811, 819, 823, 828, 838, 840, 842, 846, 897,

914, 930, 936, 940, 999, 1017, 1033
Equivalent gradient, E-754, 889, 936

Linear gradient, E-86, 479

Bilinear gradient, E-282

Non-linear vertical gradient, E-400

Horizontal gradient, E-1000

Vertical gradient, E-1000

Average gradient distribution, E-999

Distribution classifications, E-53, 248, 433, 688

Statistical distribution, E-999

Distribution predictions, E-33, 618, 693

Fluctuations, E-58, 70, 81, 100, 102, 110, 159, 166, 196, 198, 210,

225, 244, 274, 281, 295, 344, 374, 416, 457, 477, 478,

492, 496, 527, 529, 531, 541, 542, 556, 565, 682, 779,

915, 1017, 1077

Index curves classification, E-33, 567

M - curve, E-33, 35, 59, 109, 123, 339, 420, 548, 557, 558,

776, 862, 1061

N - curve, E-339, 453, 804, 821

Index computation, E-79, 122, 146, 176, 222-224, 250, 278, 399

Index forecasting, E-194, 236, 595

Index analyses, E-501

Index sea level values, E-610-612, 695, 696, 752

Index surface values, E-803, 309, 819, 842, 1011

Index soundings, E-241, 917

Soundings of nitrogen, E-251, 292, 813

Soundings of oxygen, E-251, 292, 813

Soundings of carbon dioxide, E-251

Soundings of water vapor, E-251, 292

Soundings of argon, E-292, 813

Mapping, E-641, 695

Sea level charts, E-931

Prediction tables, E-694, 695, 930

Measurement methods, E-929

Data centers, E-1044

Influences on the refractive index

by topography, E-124

by latitude, E-124

by water drops, E-212

Review of influences, E-483

Refractive co-index, E-999

Modified refractive index, E-73, 109, 140, 144, 173, 341, 414, 453,

548, 724, 862

Optical refractive index, E-172

Potential refractive index, E-902

Bi-exponential model, E-804

Sub-refraction, E-1099

4. Air maspes, E-55, 107, 187, 197, 239, 263, 281, 307, 400, 605, 610, 696,

755, 916, 972

Continental, E-843

Polar, E-206, 612, 673

Maritime, E-581, 843
XI

Moist, E-115, 206, 374, 581, 915

Monsoon, E-58

Tropical, E-58, 206, 843

Unstable, E-843

Inductive capacitances, E-876

5. Fronts, E-52, 55, 65, 167, 310, 377

Structure, E-942

Coastal fronts, E-249

Cold fronts, E-22, 40, 108, 612, 641, 921

Arctic fronts, E-637

Polar fronts, E-612, 637

Warm fronts, E-40, 610, 921

6. Turbulence, E-93, 101, 110, 127, 135, 206, 211, 240, 257, 282, 301, 309,

310, 318, 322, 335, 343, 345, 394, 463, 470, 492, 495,

506, 516, 529, 531, 542, 565, 588, 590, 594, 597, 649,

657, 664, 676, 704, 766, 771, 719, 785, 786, 852, 915,

923, 934-937, 939, 942, 943, 952, 968, 1002, 1049

Microstructure, E-377, 660

Eddies, E-149, 330, 531, 915, 916, 937

7. Winds, E-36, 55, 78, 102, 183, 256, 257, 278, 365, 404, 469, 524, 625,

755, 877, 925, 940, 1034

Cirocco, E-l

Air flows, E-339, 1037

Anticyclones, E-28, 487, 546, 560

Anticyclonic regions, E-860

Anticyclonic conditions, E-1007

Cyclones, E-l, 28, 377, 438

Gales, E-l

Trade winds, E-869

Tsunamis, E-377

Wind velocities, E-340, 973, 1034

Storms, E-l, 29, 215, 612

Monsoon storms, E-438

Rainstorms, E-317, 344, 932, 977, 1004

Snow storms, E-10, 398

Thunderstorms, E-10, 298, 438, 514, 567, 925, 978

Lightning, E-1085

Clouds

Cumulus, E-374, 484, 531, 661

Stratocumuli, E-524

Thunderclouds, E-77, 439

Cloud structure, E-438

Cloud scattering, E-113

Cloud base heights, E-861
Xll

10. Atmospheric altitudes, E-153, 214, 1046

Meters Km.

100 m<sters E-615 0-1 km. E-897

125 E-274 0.25 E-502

128 E-274 1-2 E-21

300 E-662, 916 3 E-805, 808

«= 500 E-327 4 E-502

500 E-155,469, 735 6 E-58

600 E-88 8.45 E-662

750 E-409 <10 E-175, 188

1000 E-703, 753, 862 18 E-25

1140 E-409 0-20 E-776

1500 E -862, 916, 1032 1-20 E-273, 322

2000 E-904 20 E-846

3000 E-151 0. 1-70 E-694

8000 E-154

Feet

1 f t. E-101 30-7800 ft. E-203

2 E-101 1000-8000 E-24

3 E-101 8000 E-383, 485

« 15 E-261 9800 E-525

32 E-101 3000-10,000 E-223

50 E-40, 101, 159 10, 000 E-79, 195,418,

100 E-40, 78, 127, 166 588, 861

=» 100 E-54, 55 11,000 E-196

150 E-40 6220-14,110 E-355

200 E-40, 621 20, 000 E-79, 195, 281,

8-220 E-204 285

300 E-40 25, 000 E-281

350 E-166 30, 000 E-79

400 E-1017 40, 000 E-142

600 E-334 60, 000 E-385, 622

900 E-1017 70, 000 E-1017

0-1000 E-145 100, 000 E-522

1000 E-40 130, 000 E-441

1200 E-1017

1000-2000 E-145, 942

2000 E-209, 861

2200 E-307, 577

«<3000 E-755

3000 E-222,637, 723

3800 E-257

4000

4560

E-485, 869

E-189

Millibcirs < 5000 E-131 1000 mb E-1084

5000 E-550, 580, 948, 900 E-921,951, 1084

1017 950-900 E-176

4000-6000 E-581 850 E-999

6000 E-861 700 E-176, 474

7000 E-146, 838 500 E-400, 862
Xlll

11. Miscellaneous

Atmospheric fine structure, E-345. 455, 902, 976

Atmospheric vertical structure, E-1033, 1040

Atmospheric vertical motion, E-400, 469-471, 599

Atmospheric gases

Atmospheric argon, E-164

Atmospheric oxygen, E-164, 640

Atmospheric nitrogen, E-164

Atmospheric water vapor, E-640

(See also humidity, moisture, water vapor)

Atmospheric stability, E-846, 847

Atmospheric thermodynamic stability, E-569

Atmospheric convective activity, E-374, 404

Atmospheric density, E-613

Atmospheric mirage, E-163

Atmospheric inhomogeneities, E-344. 345, 470, 493, 506, 543, 544,

556, 661, 670, 682,

12. Ionosphere, E-544, 687, 769, 1024

Upper air conditions, E-284, 469

Scattering, E-448, 468

Meteor scattering, E-488, 646, 708, 726,

Ionized regions, E-453, 493

Auroral displays, E-20

IV. PHYSICO - CHEMICAL FACTORS AND PROCESSES

1. Scattering, E-82, 87, 110, 135, 149, 183, 188, 210, 219, 254, 265, 283,

295, 309, 310, 317, 318, 321, 331, 332, 335, 342-

344, 363, 382, 406, 416, 417, 455, 462, 496, 498,

500, 508, 520, 529, 532, 549, 557, 561, 578, 584,

589, 594, 596, 599, 600, 605, 607, 632, 637, 643,

649, 660, 662, 671, 674, 680, 700, 707, 712, 749,

754, 755, 758, 764-766, 769, 779, 788, 792, 794,

797, 810, 818, 836, 844, 848, 851, 852, 859, 864,

873, 898, 912, 913, 923, 927, 937, 944, 997, 1028,

1034, 1049

Mechanisms, E-362, 494, 496, 506, 519, 852, 950

Angles, E-507, 508, 538, 634, 748, 852, 873, 1035

Coefficients, E-927

Doppler shifting, E-494

Cross section, E-1034

Distribution of scatterers, E-533, 639

Scattering from inhomogeneities, E-425, 642, 668, 682, 726, 792, 834,

836, 949, 950

Scattering from terrain, E-830, 859, 995

Scattering from rough land surfaces, E-352, 503, 628, 793

Scattering from rough sea surfaces, E-519, 532, 587, 834, 995

Scattering from drifting of scattering centers, E-844

Scattering from moving layers, E-1035

Scattering from wavy layers, E-937

Scattering from refractive absorbers, E-1028

Scattering from "chaffs", E-831

Scattering from sinusoidal surfaces, E-520

Scattering from trochoidal surfaces, E-520
XIV

2. Reflection, E-l, 6, 10, 17, 20, 22, 28, 54, 66, 72, 77, 82, 83, 87, 95, 132,

133, 188, 225, 318, 393, 406, 455, 469, 471, 476,

484, 583, 605, 678, 754, 769, 847, 910, 916, 967,1057

Coefficients, E-801, 1082

Partial reflection, E-715, 755, 772, 785, 786, 900, 945, 952

Specular reflection, E-901

Double reflection, E-13

Reflection from air mass boundaries, E-605, 714, 852

Reflection from tropospheric layers, E-149, 708, 777, 785, 786, 922, 990,

1026, 1040, 1041

Reflection from tropospheric inhomogeneities, E-425, 642, 726

Reflection from clear air strata (angels), E-1032

Reflection from ground, E-45, 137, 138, 201, 844, 911

Reflection from coastlines, E-1023

Reflection from rough sea surfaces, E-532, 834, 973, 1052

Reflection from rough terrain, E-445, 503, 651, 1019, 1082

Reflection from ice, E-118

Reflection from sand, E-57

Reflection from snow, E-118

Reflection from water, E-45, 357, 444

3. Refraction, E-7, 10, 17, 19, 26, 35, 39, 47, 52, 55, 65, 72, 82, 86, 115-

117, 126-128, 137, 149, 150, 154, 155, 165, 172,

175, 179, 201, 221-223, 252, 300, 301, 309, 310,

321, 339, 396, 415, 423, 433, 443, 457, 483, 493,

502, 508, 531, 593, 604, 633, 653, 657, 677, 681,

688, 693-698, 708, 726, 742, 769, 803, 811, 819,

822, 834, 853, 868, 879, 886, 887, 903, 907, 915,

921, 936, 961, 970, 991, 994, 997, 1006, 1040,

1041, 1057, 1059

Prediction, E-615

Molecular refractivity, E-807

Water drop refractivity

Superrefraction, E-36, 39, 41, 56, 61, 73, 93, 95, 103, 109, 117, 126, 156,

178, 188, 194, 208, 237, 240, 249, 282, 284, 327,

339, 365, 372, 385, 425, 437, 438, 454, 539, 541,

567, 806, 860, 925, 940

Prediction, E-365

Nocturnal, E-135

4. Diffraction, E-6, 17, 19, 31, 42, 70, 86, 93, 108, 137, 138, 150, 201, 217,

219. 299, 304, 373, 406, 455, 459, 472, 485, 551,

560-562, 568, 691, 692, 709, 718, 726, 744, 795,

836, 838, 844, 848, 876, 885, 899, 956, 985, 994,

1006, 1055, 1057, 1091

Knife edge diffraction, E-201

Loss, E-96, 328, 551

Zones, E-248

5. Absorption, E-3, 10, 82, 87, 121, 356, 683, 769, 827, 888, 972, 976

by02

, E-62, 264, 441, 770, 775, 827, 871

byH2

0, E-62, 264, 441, 518, 770, 775, 827, 871, 905, 1031

by 3

, E-827

by N2

0, E-827

by fog, E-871
6. Attenuation, E-26, 43, 44, 87, 147, 201, 214, 237, 298, 366-368, 560, 561,

578, 594, 640, 727, 774, 775, 801, 888, 905, 954,

988, 1024, 1028

by 2, E-506, 640, 729

by

3

, E-214

by H20, E-214, 502, 640, 729

by duct layers, E-339, 546

by fog, E-621

7. Scintillation, E-120, 210, 317, 344, 423, 502, 524, 682

Frequency correlation, E-1005

8. Dielectrics

Dielectric constant, E-77, 87, 94, 99, 100, 115, 134, 141, 233, 289,

415, 440, 507, 642, 644, 664, 738, 742, 761, 872,

954, 977, 983

Fluctuations, E-344! 434^ 515, 516, 649, 755, 836, 859, 1034, 1086

Irregularities, E-424, 448, 494, 649, 712, 723

Survey, E-426

Loss, E-90, 872

Noise, E-617, 707

Wedges, E-108

Plane layered dielectrics, E-1003

Distribution, E-318

Boundary conditions, E-691, 1036, 1086

Spectrum, E-852

Discontinuities, E-849

Transmitivity fluctuations, E-766

Magnetic field intensity, E-3, 9, 12

9. Surface conductivity, E-34, 252, 262, 432, 440, 644, 645, 983, 995, 1025,

1027, 1086

Seasonal variations, E-977

Sea conductivity, E-1025

Great Lakes, E-977

Contrasts near coastlines, E-960

-of different soils, E-1027

-of rocks, E-1027

-of snow, E-1027

-of ice, E-1027

-of permafrost, E-1027

10. Ionization, E-12, 77, 82, 453

Electron density, E-896

Free electron lifetime, E-12

11. Miscellaneous

Solar activities, E-10, 12, 25, 397, 544, 890

Auroral displays, E-20

Cosmic rays, E-12

Meteor scattering, E-646, 708, 726, 1043

Radio stars, E-397
XVI

V. WAVE CHARACTERISTICS

1. Frequency bands

EHF (extremely high frequency) > 30 Kmc/s or < 10 mm A . E-62, 118, 208,

214, 216, 221, 261, 264, 336, 502, 519, 546, 640, 770, 982

SHF (super high frequency) 30 Kmc/s to 3 Kmc/s or 10 to 1 cm A , E-35, 41,

45, 67. 70. 79. 86. 90, 93, 96, 102. 104, 118, 127, 128.

147. 148, 164. 182-184, 191. 214, 240, 280, 283, 285, 288.

312. 313, 318, 339, 343, 356, 357. 362, 444. 518. 519. 544.

557. 560, 561. 570. 604, 635. 640. 652. 722, 729. 777, 982

UHF (ultra high frequency) 3000 Mc/s to 300 Mc/s or 10 to 1 dm A . E-16,

31, 35, 37, 79. 84, 86, 94, 96, 97, 118, 127, 128, 135,

137, 142, 154, 160, 162, 163, 172, 185, 187, 201, 207, 217,

237, 239, 240, 271, 280, 282, 283, 285, 294, 298, 300, 301,

308. 309, 312, 313. 315, 318, 322, 324, 328, 333, 343, 353.

354, 356, 357, 362, 395, 397, 401, 439, 451, 456, 463, 472,

473, 486, 490, 525, 539, 551, 572, 593, 615, 633, 648, 649,

673, 700, 703, 727, 732, 745, 755, 757, 764, 767, 777, 789,

799, 815, 828, 836, 837, 839, 857, 902, 904, 921, 922, 984,

990, 1021, 1033, 1054, 1057, 1072, 1109

VHF (very high frequency) 300 Mc/s to 30 Mc/s or 10 to 1 m A

E-17, 18,

23, 24, 32, 35, 45, 47, 54, 62, 72, 81, 82, 84, 86, 87, 93,

97, 106, 114, 116, 118, 128, 137-139, 142, 149, 151, 152,

154, 163, 167, 174, 176, 180, 185, 187, 199, 207, 217, 219,

230, 231, 235, 236; 239, 240, 247, 248, 252, 254, 256—258,

263, 267, 268, 273, 282, 284-286, 291, 295, 298, 300-302,

308. 310, 311, 313, 314, 318, 322, 328, 333, 342, 353, 354,

356, 357, 382, 383, 388, 390-393, 395-397, 400, 411, 412,

422, 426, 448, 455, 456, 469-471, 474, 481, 486, 490-493.

497, 504, 505, 508, 517, 518, 524, 525, 536, 543, 548, 549,

551, 552, 559, 565, 571, 572, 580, 582, 596, 598, 615, 648,

662, 664-666, 670, 680, 685-687, 690, 708, 714, 717, 726,

730, 731, 734, 738, 739, 745, 755, 767, 777, 783, 785, 786,

789, 796, 799, 805, 833, 876, 887, 902, 914, 921, 930, 931,

945, 953, 969, 983, 984, 990, 1021, 1042, 1043, 1057, 1066, 1074

HF (high frequency) 30 Mc/s to 3 Mc/s or 100 m to 10 m A . E-673, 750, 874,

1053, 1066

MF (medium frequency) <3 Mc/s or 1000 to 100 m A, E-338, 429, 432, 673

LF (Low frequency) < 300 Kc/s or 10 to 1 km A. E-408, 429, 432, 510, 514,

646, 737, 1066

VLF (very low frequency) < 30 Kc/s or 100 to 10 km A . E-432, 514, 737, 1024,

1066, 1085-1095

ELF (extremely low frequency) <"3 Kc/s or r 100. 000 km A. E-432, 514

Miscellaneous frequency bands

X - band, E-444, 570, 722, 982

S - band, E-722

L - band, E-570

I -V band, E-333, 472, 984, 1007

Wide band of noise, E-1022
XVI

2- KMc/s (GC/s) , Me/s, Kc/s and Cps

KMc/s - Gc/s

10 Kc/s 100 Kmc E-659 1-10 Kmc E-640

70.1 M E-264 «1D " E-729

69.9 1* E-871 9.35 " E-1003

69.5 M E-264 5

" E-1000

10-50 n E-S19 4.11 " E-647

O. 5-40 •*> E-640 3.12 • E-599

36 M E-546 3

" E-777

15 n E-518 1.3 N E-700

11 H E-635, 729 1.1-1.2 n E-700

10 n E-777, 838 >1 u E-821

3-10 IV E-826

Mc/s

100-50,000

36,000

30, 000

29,500

24,000

15,000

7000-12000

10, 000

100-10, 000

50-10, 000

30-10, 000

9640

9400

9375

9350

9300

9250

9150

9000

8350

8000

6800

6770

5050

5000

4000-5000

4110

4090

4000

100-4000

40-4000

3840

Mc/s E-E

E

E

E

E

E

E

E

356,441

-546

-118

-160

164

518

972

577, 729

462, 888,

1097

-711,944

359

722,826

215, 127,

447,677,

780

86,240,482,

240, 656

288,965

-965

965

-312

-90

-1004

-1004

-916

1032

-338

378

-713

620

280

-191,339,

746

-453

190

-722,826.

844

3700

3480

3300

3000

30-3000

2880

2860

2800

2780

2720

2300

2290

2120

2000

1970

1750

1310

1300

1250

1200

1089

1047

1046

100 - 1046

92 - 1046

66 - 1046

60 - 1046

1000

100 - 1000

970

960

Mc/s E-240

E-523

E-215, 952

E-86, 240, 311,

367. 557, 577,

653,666,872,

937

E-328

E-339

E-127

E-55

E-312

E-625,626

E-558

E-616

E-730,731,

989, 990

E-673,912,

913, 706

E-673

E-521

E-127

E-G37

E-581

E-328

E-385

E-240

E-271,237,301,

569, 651, 1044

E-203

E-272,319

E-322

E-308

E-86, 185, 673

E-304, 354, 902

E-921

E-375
XV111

Mc/s (cont'd. ) 92-1046 Mc/s E-1045 265. 3 Mc/s E-921

950 E-674 250 E-872

915 E-802 220-250 E-89

900 E-350,689, 238 E-364

717, 743. 220 E-603,861,869,

809, 946, 1074

1101 218 E-385

700-900 E-673 210-216 E-268

630-900 E-545 203.5 E-565

880 E-674 200 E-741,912

858 E-578, 579 100-200 E-18, 66

850 E-201 40-200 E-411

810 E-674 30-200 E-106

800 E-673, 746, 180.4 E-307

751 156-174 E-734

400-800 E-462 173 E-298

50-800 E-258 172. 8 E-291,301

751 E-799 170 E-86, 692

600 E-16,259, 551, 160.2 E-217

572, 730, 160 E-215

777, 989 159. 49 E-551,572,731,

599 E- 731, 990 990

547 E-378 153 E-163

540 E-328 152. 05 E-685

533 E-324 150 E-167,524,690,

520 E-86 777

505 E-398, 280 141 E-988

500 E-361,451,637, 128 E-953

716,912 110 E-31

100-500 E-353 108 E-448, 962

445 E-1074 100 E-118,185,206,

492 E-298 259, 273, 305,

490 E-636 328,355,378,

474 E-55 703,872,912,

472 E-163 913

471 E-847 88.5 E-347

460 E-620 88-100 E-219,474

450 E-160, 759 87. 5-100 E-254

430 E-703 99.9 E-1031

418 E-385, 736 97. 8 E-347

417 E-616, 720 96.3 E-256

416. 7 E-815 94. 35 E-487

412. 85 E-539 93 E-179, 240

412 E-135 92.9 E-179

410 E-240 92.1 E-116

403 E-622, 896 91.3 E-418, 588

400 E-751,815, 91 E-298

870, 894, 90 E-149

986 89 E-176

300-400 E-401 86 E-577

388 E-815 80 E-548, 724

387 E-142 30-70 E-517

300 E-118,872 68 E-247

30-300 E-303 65. 28 E-382

297 E-364 65 E-167

280 E-142 63 E-86
XIX

Mc/s (concl'd. ) Kc/i

> 60 Mc/s E-65, 1075 3492. 5 Kc/s E-21

60 E-37, 163, 2398 E-21

524,690 1614 E-21

25-60 E-490 1000 E-1025

55 E-31 200 E-429

52 E-378 100 E-429, 1025

50 E-26, 240, 1043 50 E-429

49 E-298 40 E-429

45. 1 E-55 30 E-429

45 E-149 20 E-429, 1025

44. 1 E-116 10 E-429

42.8 E-52 10 Kc/s-100, 000 M<3 /s E-659

41 E-247 < 10 Kc/s E-1024

>40 E-456

>30 E-87,130, 276,

771,930

30 E-118, 1069

25 E-86

20 E-647

3-20 E-750

E-667,872

E-1081

E-946

E-1069

E-673

E-689

Cds

10 1000 Cps E-647

6

4.2

3

2-7

2

200 cp-500 Kc/s E-432

100 cp-1000 Kc/s

—30 cps — 10 cps

E-737

E-1068

E-1027

1.5 E-872

1.3 E-338

Miscellaneous

Frequency dependency, E-758, 815, 829, 884, 990

Frequency correlation of radio waves, E-891

Frequency correlation of signal scintillation, E-1005

Frequency fluctuations, E-939, 967

Frequency bandwidth, E-295, 738, 852, 890, 967

Bandwidth capabilities, E-295, 338, 424, 462, 468, 490, 682, 731, 816,

848, 857, 863, 946, 1009

Frequency allocations, E —1062

Voice frequency, E-1030

Sweep frequency studies, E-647

3. Wave lengths, E-12, 738, 796

mm A. E-62. 214.877.1037

2. 5 mm, E-62

3.35 " E-502

4.3 " E-261,264, 502

6 E-62

8 E-770

8.6 " E-261,419, 502,

905

8-40 " E-1052

Cm X , E-19, 73, 83, 214, 278, 406,

783,961.962,1067

1 Cm E-128, 147

1. 25 " E-41, 160

1. 5

" E-122

=» 1. 5

" E-224

3

" E-45, 59, 73, 83, 93,

147, 183, 204, 228,

454, 567, 838, 860,

925,940,1065
XX

Cm A (cont'd.

=» 3 Cm E-57

3, 1

" E-lll

3.2 " E-59, 120,261.

297,340,544,

560,932, 1079

4. 7 " E-585

6 " E-300

6-10 " E-932

6. 4 E-297, 1058

E-340

E-45,82,83,183

E-44

m E-43

E-1080

E-43

Cm E-585

E-lll

E-297, 1058

E-93

E-340

E-345

E-57

E-361

E-870

E-823

2

2 cm-11.5

10 cm

10 m-10 cm

10.7

16.2

17

23

24

25

1-42

60

75

86

dm A , E-19,47,76,150,278,

783.406.525.633

1. 07 dm E-585

1.62 E-lll

1.7 E-297

2.3 E-93

2.4 E-340

2.5 E-345

6.0 E-361, 228

7.5 E-870

8.6 E-823

M A, E-19, 149,150,278,406,470,

471. 491, 525, 565, 566, 594. 1078

1.36 m E-687

1.4 E-326

1.6-5 " E-23

2 E-85, 114

3 E-152,206,310,392,

396, 1072

3.5 E-45

3.4 E-176, 843

3. 75 E-548

5 m - 2 cm E-842

1. 9 E-72

10 E-128

«= 10 E-56,85,325,406

10 m-10 cm E-43

14 m E-15

50 E-15

125 E-485

Miscellaneous

Wavelength dependence on distance, E-617, 738

4. Propagation modes, E-188, 785, 786, 1085

Scatter propagation, E-321, 345, 380, 403, 410, 426, 488, 490, 555,

571, 623

Ground wave propagation, E-258, 428-432, 450, 499, 509-513, 534, 563,

591, 592, 655, 679, 702, 737, 740, 880, 885,

906, 907, 955, 988, 995, 1003, 1023, 1025, 1039

1081, 1086, 1095

Duct propagation, E-36, 67, 73, 200, 269, 741

Reciprocal propagation, E-685

Ionospheric propagation, E-314, 319, 321, 332, 345, 349, 901,1075, 1098, 1100

Studies, E-75, 182, 183, 192, 201, 204, 206, 320, 321, 360, 367, 368,

371, 375, 380, 394, 420, 423, 425, 429, 432,

441, 443, 450, 457, 466, 470, 477, 488, 490,

492, 509, 543, 553, 554, 557, 562, 563, 591,

592, 616-618, 620, 627-629, 649, 714, 741, 785,

786, 944, 949, 966, 967, 975, 1003, 1005, 1019,

1024, 1026, 1029, 1065, 1075
XXI

Mechanism, E-296, 426, 459-471, 492, 505, 515, 519, 546, 553, 555, 565,

567, 584, 588, 618, 620, 623, 625, 630, 649,

656, 708, 714-716, 726, 741, 755, 760, 785,

786, 796, 877, 880, 911, 937, 952

Velocity, E-3. 79, 291

See also VI. Radio Communication

5. Fading, E-81, 91, 111, 147, 179, 191, 215, 229, 235, 237, 261, 286, 294,

297, 298, 302, 308314, 338, 366, 393, 426,

462, 469, 481, 494, 518, 524, 539, 557, 559,

579, 581, 620, 626, 627, 656, 666, 670, 682,

755, 769, 783, 826, 856, 874, 907, 912, 920,

952, 1046, 1049-1051, 1058, 1097

Mechanism, E-23, 382, 420, 643, 1061, 1065

Fading rate, E-39, 340, 382, 494, 523, 579, 601, 625, 637, 670, 690, 722,

751, 844, 861, 913, 1026, 1075

Rapid fading, E-669, 699, 738

Slow fading, E-738, 742, 865

Short term fading, E-965

Duration, E-720, 722, 743, 913

Fadeouts, E-237, 881

Selective fading, E-730, 863, 894, 988

Fading regions, E-821, 992

Doppler shift, E-1026

6. Echoes

New type, E-571

Short range echoes, E-834

From cloudless sky (radar angels), E-178, 404, 457, 528, 556, 605, 606,

823, 916, 938, 958, 1032

From horizontally stratified atmosphere, E-189, 1080

Angle of arrival, E-41, 69, 87, 99, 160, 317, 344, 538, 894, 1026,1079,1097

Amplitude, E-23, 423, 590, 643, 653, 654, 682, 699, 730, 737, 739, 779, 826,

844, 884, 922, 923, 934, 943, 945, 949, 952,

956, 973, 975, 998, 1023, 1025, 1048, 1050

Gaussian, E-743

Phase, E-423, 590, 643, 652-654, 677, 682, 699, 737, 779, 845, 864, 884,

923, 934, 939, 943, 949, 956, 973, 975, 998,

1003, 1023, 1025

Polarization, E-397, 411, 456, 543, 579, 720, 738, 744, 774, 884, 896, 973, 988

Horizontal, E-23, 32, 43, 48, 84, 86, 519, 659, 702, 844, 984

Vertical, E-23, 32, 48, 84, 192, 519, 598, 653, 702, 839, 984

7. Miscellaneous waves

Alfven's hydromagnetic waves, E-67

Creeping waves, E-1028

Gravity waves, E-377, 1032

Ground waves, E-4, 30, 80, 226, 252, 258, 266, 303, 319, 408, 429, 510,

511, 631, 655, 659, 667, 1081, 1086, 1095

Field strength, E-80, 270

Surveys, E-259

Atlases, E-203

LF, E-408, 509, 513
Internal tropospheric waves, E-910

Light waves, E-230

Ocean waves, E-444

Polarized waves, E-598, 659, 839, 844

Sonic waves, E-890

Surface waves E, E-591

Surface waves H, E-591

Surface waves, Norton's, E-466

Surface waves, Sommerfield's, E-407

Tidal waves, E-890

VLF waves, E-1024

VI. RADIO COMMUNICATION

1. Experimental transmission, E-l, 7, 10, 29, 45, 53, 70, 75, 87, 110, 112, 114-

116, 142, 147, 183, 201. 203, 204, 206, 217,

247, 257, 271, 272, 280, 283, 286, 288, 311,

312, 315, 319, 324, 338, 345, 350, 367, 390,

398, 411, 461, 530, 537, 565, 566, 620, 674,

688, 731, 815, 816, 831, 837, 846, 847, 921,

952, 1045, 1065, 1076, 1106

Multichannel, E-4, 316, 338, 350, 475, 663, 689

Multichannel telephony, E-575, 663, 673, 932

Simultaneous recording, E-26, 111, 280, 390, 616

Beam swinging, E-599, 619, 647, 692, 732, 852, 922, 937, 990

TV, E-333, 338, 410, 467, 468, 490, 500, 545, 549, 978

Radio telephone tests, E-364, 410, 486, 490, 545, 627, 650, 673

Laboratory experiments, E-60, 316, 987, 1030

Intermittent teletype VHF transmission, E-686

Two-path transmissions, E-858

FM radio links, E-575, 663, 739, 829, 848, 932

Interurban TV, E-575

TV, E-582, 648, 727, 829, 928, 932, 1007

Digital information, E-817

Facsimile information, E-817

2. Transmission losses (See also IX. Pt.4), E-190, 199, 203, 213, 218, 236, 272,

273, 286, 305, 308, 311, 322, 340, 353, 390,

391, 403, 441, 450, 462, 472, 486, 495, 523,

525, 569, 572, 577, 600, 603, 616, 625, 636,

658, 659, 667, 686, 687, 703, 709, 714, 720,

722, 721, 731, 736, 738, 758, 760, 765, 766,

789, 796, 797, 799, 800, 805, 828, 833, 843,

852, 887, 894, 897, 916, 918, 922, 998, 990

1045, 1046, 1051

3. Forecasting conditions for radio communication, E-35, 37, 38, 106, 163, 183,

269, 296, 308, 312, 322, 368, 443, 477, 480, 667,

712, 718, 719, 773, 797, 800, 882, 890, 931, 941,

995. 1009, 1070

From refractive index surface values, E-803, 809, 819, 879, 970

From meteorological conditions, E-580, 595, 615, 755, 805, 819, 874, 877,

940

Radar transmission, E-339, 385, 1105

Radio station areal coverage, E-381, 837, 992, 1021

TV station areal coverage, E-648, 731, 745, 818, 837, 992,1054,1076,1103

Radar range, E-1064, 1099
XX111

Teletype areal coverage, E-619, 686, 818, 1030

Telegraphy, E-714, 1030

Telephone, E-650, 709, 714, 818, 1021

Voice communication, E-619, 627, 1030

4. Effects on radio communication

Meteorological, E-22, 33, 35, 37, 39, 50-52, 55, 57, 64-66, 68, 83, 85, 87-

89, 91, 104, 106, 111, 112, 115, 117, 121, 127,

139, 147, 149, 152, 163, 166, 176, 178, 200,

206, 236, 249, 252, 254, 297, 300, 309, 310,

317, 343, 356, 383, 385, 473, 482, 497, 514,

521, 524, 528, 530, 560, 561, 566, 569, 570,

579, 593, 609, 615, 616, 621, 648, 656, 660,

667, 678, 688, 700, 703, 714, 724, 738, 755,

781, 846, 847, 852, 914, 925, 976, 978, 989,

1002, 1061, 1105

Weather, E-28, 29, 39, 66, 176, 275, 326, 398

Radio communication - meteorology interdependency, E-39, 347, 365, 392, 437,

443, 461, 483, 572, 581, 595, 626, 714, 724,

753, 758, 762, 784, 793, 809, 828, 881, 886,

914, 921, 936, 937, 1002, 1007, 1013, 1017,

Atmospheric stability, E-846, 847

Atmospheric inhomogeneities, E-935, 911

Atmospheric vertical motions, E-400

Turbulence, E-65, 230, 506

Boundary conditions, E-691

Internal tropospheric waves, E-910

Troposphere height, E-636

Ground moisture, E-702

Diurnal factors, E-57

Twilight, E-7

Snow, E-420

Dust, E-l

Tropospheric influence on satellite communications, E-962, 963

Doppler shift, E-627, 991, 1056

Nuclear bursts, E-1053

5. Terrestrial effects

Earth's surface, E-594, 740, 899, 966, 1076, 1086, 1088, 1089

Earth's shadow, E-ll, 32, 42, 43, 47, 66, 97, 201, 358, 662, 845, 934

Earth's brightness, E-6, 845, 934

Tonography, E-l, 17, 64, 82, 127, 138, 162, 199, 217, 218, 403, 411, 413,

472, 554, 667, 714, 750, 799, 1019

Ground conditions, E-3, 44, 45, 47, 127, 138, 236, 253, 411, 412, 419,

428, 429, 467, 472, 1076,1086,1088-1090

Rough terrain, E-223, 240, 272, 390, 419, 901, 966,1045,1052,1055,1090

Say/ tooth surfaces, E-794

Cliffs, E-906

Bluffs, E-906

Mountains, E-199, 258, 286, 308, 373, 459, 554

Mountain ridges, E-631, 906, 989, 1087

Mountain knife edge effect, E-593, 798, 799, 881, 1046, 1106

Foreground, E-218, 593, 743, 781, 799, 839

Inhomogeneous surfaces, E-629

Irregular terrain, E-63, 135, 138, 162, 217, 223, 240, 258, 259, 328,

391, 456, 459, 648, 678, 960, 981, 1038
XXIV

Terrain shielding, E-1004

Vegetation, E-648, 702, 839

Forests, E-727, 743

Trees, E-328, 727

Sea

Oceanic swell, E-182

Salt particles, E-l

Sea spray, E-78

Noises, E-64, 124, 157, 182, 314, 451, 514, 535, 760, 816, 837, 932,

1022, 1096

Countermeasures, E-837, 1022

Spherics, E-l, 7, 10

Thermal noise, E-640, 720, 800, 888, 1096

Oxygen, E-640

Water vapor, E-640

"Spikes", E-439

White noise, E-732, 1085

Cross noise, E-855, 932

Transient noise, E-858

Dielectric noise, E-617

Intermodulation distortion, E-767, 816, 920, 747, 1009, 1011

Pulse distortion, E-557, 626, 627, 738

6. Miscellaneous

RFI (radio frequency interference, E-190, 314, 360, 523, 632, 907, 1009, 1021

Aircrafts, E-523, 579, 973

Masking, E-621

Conductivity, E-34, 238, 266, 467, 960

Path lengths, E-135, 976

Magnetic disturbances, E-329

Extraterrestrial, E-837, 976, 1002

7. Reception

Field strength, E-13-15, 19, 26, 30, 38, 43, 48, 55, 70, 81. 91, 93, 105, 111,

132, 142, 147, 149, 166. 179, 185, 187, 191, 201,

206, 208, 213, 223, 228, 230, 248, 258, 261, 262,

282, 296, 297, 299, 307. 309, 310, 313, 314, 318,

327, 328, 347, 355, 392, 418, 422, 426, 432, 434,

594, 597, 603,60 , 610, 675, 678, 700, 725-727,

732, 736, 764, 769, 772, 774, 786, 796, 799, 805,

809, 832, 843, 847, 856, 857, 861, 874, 877, 878,

907, 912-914. 921, 928, 945, 960, 969, 983, 984,

992, 1007, 1015, 1018, 1026, 1074, 1076

Reflected field, E-772, 878

Diffused field, E-772

Beyond horizon, E-16, 17, 19, 37, 39, 48, 81, 133, 149, 216, 219,237,

254, 263, 271, 279, 282, 301, 316. 322, 325, 326,

345, 367, 386, 406, 453, 468, 477, 493, 558, 559.

570, 577, 582, 588, 597, 599. 600. 605, 618, 620,

666. 682, 890, 716. 717, 732, 755, 843, 847, 962, 1043

Field intensity measurements, E-151, 162, 163, 172, 184, 266, 267, 270,1057

Field intensity of ground waves, E-80, 258, 259, 679, 702, 820

Statistical evaluation, E-576, 878, 952, 1048, 1058

Within optical range, E-317, 322, 373, 632
Rayleigh Distribution, E-320, 445, 521, 539, 584, 601, 626, 630, 643, 651,

699, 718, 743, 844, 945, 973, 1030. 1058

Daily variation, E-309, 473. 474, 497, 548, 690, 724, 735

Hourly variation, E-336

Prediction, E-312, 611

Annual variation, E-473

Mean skip distance, E-323

Seasonal variation, E-497, 690, 743

Scatter fields, E-345, 356. 358, 463. 1048

Radio communication paths

Types of paths, E-17, 23, 215

Air-to-air, E-130, 132, 157, 170, 1074

Air-to-ground, E-130, 142, 157, 170, 486, 953

Beyond the horizon,

Great circle path, E-577

Ground-to-air, E-24, 1074

Ground-to-ground, E-308, 1074

Line of sight, E-317, 344, 354, 371, 463, 652, 654, 657, 669, 717, 790, 799,

939, 993

Multi path. E-160, 283, 362, 401, 409, 434, 518, 537, 560, 720, 730, 751,

790, 833, 1009, 1081

Non-optical, E-17, 18, 26, 53, 127, 150, 233, 247, 305, 334, 361, 378, 553,

554 724 831

Optical, E-93, 127, 137, 200, 319, 354, 359,361,409,434,450,1049.1057,1058

Point-to-point, E-47, 314, 391, 402, 468, 490, 655, 911

Within the horizon, E-798, 799, 838, 889, 895, 965. 1046, 1065, 1099

Over:

Land, E-l, 2, 17, 44, 45, 48, 52, 57, 82, 106, 111, 150, 152, 218, 254,

267, 285, 322, 456, 481, 487, 510, 557, 572,

659, 724, 731, 902, 962, 990, 1039

Land-sea boundaries, E-679, 740, 750, 819, 835, 885, 1006, 1023,

1025, 1039, 1047

Coastal lines, E-740, 750, 819, 885, 906, 1006, 1023

Mixed, E-262, 299, 429, 805

Mountains, E-l, 31, 199, 257, 286, 311, 783, 993, 1044, 1045

Knife edge, E-31, 96, 217, 311

Ridges, E-43

Semi tropical areas, E-218

Arctic path?, E-1070, 1098

Tradewind areas, E-1074

Snow and ice, E-420, 872

Water, E-l, 45, 48, 53, 78, 82, 83, 88,106. 115, 120, 150, 166, 178, 183,

184, 195, 196, 208. 218, 254, 267, 280, 285, 297,

313, 334, 360, 378. 409. 444, 482, 487, 509-511,

524, 530, 539, 557, 560, 565, 571, 587, 653, 656,

659, 690, 724, 751, 776, 816, 818, 819, 838, 845,

851, 852, 897, 937, 962, 977, 984, 1039, 1046,

1049, 1058, 1065, 1091, 1099

Water - land, E-10, 280, 398, 408, 510, 511, 1046

Miscellaneous

Path losses, E-218, 486, 523, 551
XXVI

Path lengths:

1.05 Mi. E-1004

3.5 ii E-264, 288, 301

7

ii E-261,264

7.5 " E-502

9.4 ti E-677

9.5 " E-780

10 ii E-301

10.3 11 E-1004

12 li E-635

21.1 ii E-334

24 li E-261

26 li E-120

27 li E-59,635

30 li E-517

33 li E-233

38 li E-45

40 " E-57

42.5 " E-55

44 11 E-261

46.3 ll E-261

50 " E-93, 298

57 11 E-45

60 ll E-83, 301

3. 5-61 n E-502

70 li E-802

70.1 li E-55, 319

80 li E-299

82 ll E-796

85 li E-637

89 li E-298

90 ll E-53,606,734

93 li E-312

97 li E-319

98 i E-579

100 ii E-135,307,441,815,

1010

101 ii E-599

105 li E-734

119 li E-312

15-120 " E-24

120 li E-734

130 li E-218

134 i E-736

150 ii E-223, 271, 385, 1017

152 li E-298

156 li E-751

161 ll E-815

167 li E-52, 116

171 li E-620, 647

173 11 E-523, 722, 826

180 li E-1042, 1101

185 i E-816

161-188 " E-283

188 ii E-338,619

196 li E-268

199 li E-298

200 N[i. E-45, 83, 267, 475,

549,579,619,725,

1109

215 E-626

226 E-319

230 E-235

232 E-809

234 E-298

240 E-364

247 E -722, 826

75-250 E-294

250 E-142,418

300 E-418,549,847

150-300 E-362

350 E-375,418

50-385 E-674

393 E-272

394 E-319

400 E-235, 267,441,468,

802, 869, 353

420 E-326,418

150-430 E-418

490 E-636

500 E-817

600 E-353, 720

100-600 E-687

617 E-272

50-620 E-355

223-628 E-203

640 E-636

724 E-539

800 E-687, 894

78-830 E-894

900 E-687

1000 E-441,603

100-1000 E-356

700-1000 E-603

800-1000 E-503

500-1200 E-861,869

2400 E-790

10-10,000 ' E-659

9000 F1 . E-444

15,000 E-444
82 nautical mile?, E-378

150 E-280

400 E-566

i> 200 mi beyond horizon E-316

200 E-525

5.2 Km E-1081

22 E-408

24 E-905

25 E-873

30 E-62

33 E-845, 653

54 E-1058

55 E-166

76 E-493

77 E-690

82 E-1058

100 E-493, 995

110 E-149

113 E-965

117 E-347

120 E-521

123 E-481

125 E- 167, 700,685

130 E-884

137 E-548, 724

40-150 E-179

150 E-152,361

160 E-149

170 E-703

180 E-71,254,470,818

194 E-913

200 E-969, 254

204 E-689

208 E-700

220 E-730, 746

XXV11

226 Km E-731

230 E-409, 843

242 E-547,913

243 E-311

240-250 E-912

258 E-361,844

260 E-557

270 E-149, 554, 703

275 E-666

280 E-551, 700, 703

300 E-275,557, 231

200-300 E-474

310 E-990

339 E-989

345 E-730, 731

360 E-743

364 E-572

370 E-569

393 E-913

398 E-844

400 E-114, 240

50-400 E-470

150-400 E-716

50-500 E-254

100-500 E-310,462

300-500 E-714

585 E-578

600 E-448, 720

300-700 E-219

100-800 E-493, 944

802 E-989

1000 E-342, 448

300-2000 E-1085

800-2000 E-493

1000-2000 ' E-490, 978

IX. INSTRUMENTS, EQUIPMENT, DESIGN CONSIDERATIONS

1. Antenna types, E-47, 322, 354, 647, 671, 749, 769, 781, 914, 1108

Dipole, E-988, 1081

Directive, E-243, 283, 574, 596, 738, 766, 795, 873, 1075, 1081

Omnidirectional, E-9888

Ground antenna systems, E-170, 429, 759

Horn antennas, E-519, 545

Inotropic, E-894

Narrow beam, E-340, 732, 918, 1015

Parabolic, E-673, 781, 1042

Passive repeater, E-217

Ship bome, E-539

Spaced antennas,

Horizontally,

Vertically, E

Fixed, E-653

Yagi, E-872

E-288, 313, 469, 495, 653,

E-736

736, 881, 912

720, 832, 844, 845
XXV111

2. Antenna characteristics

Antenna capability. E-760, 1077

Directivity gain, E-424, 662, 738, 757, 765, 767, 795, 983, 1015

Diversity gain, E-619, 731, 743, 1071

Height gain, E-47, 64, 135, 287, 294, 295, 308, 322, 335, 340, 354,

355, 386, 403, 412, 419, 456, 467, 491, 519,

523, 579, 593, 594, 625, 658, 666, 674, 678,

687, 705, 731, 733, 738, 751, 844, 884, 953, 1044, 1045

Path gain, E-634, 658, 986

Criteria for location, E-762, 1021

Electromagnetic field, E-427

Ground wave properties, E-258, 428-432

Overlapping beams, E-434

Beam widths, E-751

Fluctuations, E-707

Size, E-316, 458, 462, 506, 517, 619, 620, 890

3. System reliability, E-781, 797, 839, 854, 856, 911, 964, 1009, 1054, 1096

Antenna noise temperature, E-800

Oxygen, E-640

Water vapor, E-640

Losses, E-658, 719, 760

Antenna-to-medium coupling loss, E-625, 680, 700, 722, 833, 852,

916, 918, 998, 1008

Path loss, E-525, 572, 603, 616, 636, 687, 703, 709, 714, 720,

727, 736, 789, 797, 800, 838, 843, 894, 897

Beam deflection, E-922

In antenna gain, E-596, 738, 765, 766, 796

Loss evaluation, E-714

Loss to frequency, E-916

(See also VI. RADIO COMMUNICATION, Miscellaneous)

4. System design considerations, E-389, 495, 658, 666, 692, 703, 705, 709,

717, 739, 740, 759, 760, 762, 769, 809, 837,

851, 854, 863, 964, 1008, 1018,1051,1075,1078

5. Miscellaneous Instruments

Anticoincidence circuits, E-1022

Apparatus for measuring radio and TV station service probabilities, E-992

Automatic picture transmission

Ground stations, E-963

Balloon borne refractovariometers, E-550, 639

Balloon borne temperature sondes, E-1020

Computers

Selective fading, E-16

Analog, E-773

Systems

Communication systems, E-283, 354, 594, 601, 602, 632, 650, 680, 719,

749, 759, 760, 818, 854-856, 863, 897, 920,

984, 1008, 1096, 1101, 1110

FDM/FM scatter systems, E-500

Forward transmission echo ranging, E-75

Microwave relay system, E-70

Multi channel, E-316, 338, 1110

Radio relay, E-635, 759, 865
XXIX

Diversity Systems, E-475, 619, 625, 665, 666, 680, 706, 731, 743,

747, 757, 832, 911, 1030, 1051, 1071

Beyond-the-horizon, E-287, 316, 351, 366, 545, 665, 1018

Doppler microwave systems, E-519

Ground systems, E-870

Point-to-point scatter systems, E-984

FM, E-535, 658, 719, 854

FM relay, E-658, 1030

Multichannel mobile systems, E-734

Multichannel teletype, E-658, 719, 720, 734

Multichannel voice systems, E-706, 709, 714, 717, 734, 854,

855, 863, 920, 921, 1030, 1040, 1042

System design considerations, E-389, 495, 658, 666, 692, 703,

705, 709, 717, 739, 740, 759, 760, 762, 769,

809, 837, 851, 854, 863, 964, 1008, 1018, 1043

TV relay, E-658, 1040

Thin route (graphical) communication, E-817

Device for statistical results of variables, E-576

Direct reading microwave phase meters, E-540

Electron guns, E-791

Flat radio mirrors, E-911

Klystron (tubes) , E-673, 689, 749, 791

Magnetrons, E-722

Optical ellipsometers, E-987

Oscilloscopes, E-666

Oscillators, E-164

Hertzian, E-2, 5, 9

Crystal, E-939

Psychographs, E-146

Pulse-tune equipment, E-350

Radars, E-50, 352, 438, 454, 457, 542, 859, 889, 997, 1064

AN/CPS-9, E-528

AN/TPQ-6, E-823

CPS-9, E-925

FM, E-1001

FPS-16, E-688

MPS-4, E-585

SP - 1M, E-585

Equipment

L - radar, E-180

Radio equipment, E-21, 69, 147

Mobile, E-844

Navigational systems, E-740

Specially designed, E-316

Two-tone telegraph multiplex, E-741

USW, E-597

Radiometers, E-961

Radiosondes, E-209, 399, 710, 806, 896

Low level sounding systems, E-209
XXX

Receivers, E-16, 932

Crystal video, E-264

Equipment for statistical signal characteristics, E-768

FM, E-316

FM phase locked, E-854

Low noise, E-890

Optimum beyond horizon receivers, E-1018

Recorders

Double pen recorders, E-818

Fading rate strip-chart recorders, E-1068

Recording systems, E-302

Shaw's, E-13

Tape recorders, E-l

Refractometers, E-1107

Spectrometers, E-972

Telemetry systems, E-491

Thermistors, E-101, 102, 196

Thermometers, airborne, E-942

Transmitters, E-16

FM, E-316

High powered, E-135, 316, 890

Magnetron, E-264

Satellite relay transmitter systems, E-963

Wave meters, E-115, 291

Wind tunnels, E-987

IX. TECHNIQUES AND METHODS, Theoretical and Applied

Anderson's modified slide rule/ref. ind. calculation, E-862

Carrol and Ring's/normal wave, E-662

CCIR's method/field strength calculation, E-675

Eckersley's/calculated field strength, E-80

Feynman's diagram method, E-980

Fock's method/application, E-899

Franz's vectorial method, E-744

Galerkin's method, E-387

Kirchoff's scalar methods, E-744

Laplace's inverse transform, E-466

Leontovich and Fok's parabolic equation method, E-662

Luneberg's vectorial method, E-744

Millington's/calculated field strength, E-80

Sawyer-Bushley's/vertical velocity method, E-400

Schelkunoff's/prediction of radar prop, effects, E-269

Schulkin's high angle met, E-822

Sommerfield's scalar methods, E-744

Wegener's/calcul. inversion values, E-76

Weisbrod and Anderson's graphical method, E-822

W. K. B. 's method, E-134

Aircraft, E-40, 127, 131, 198, 241, 250, 285, 314, 402, 418, 484, 485, 588,

723, 741

Helicopter observations, E-904, 776

Angles of arrival methods, E-1079

A.M methods, E-790

Analog method for radio link performance, E-1030

Antenna gain-loss, calculation, E-766

Antenna performance, estimate, E-867
XXXI

Back scatter sounding technique, E-646

Balloon methods, E-127, 336, 491, 622, 723, 838

Bridge method, E-1027

Cavity resonator measurements, E-292

Computer methods, E-207

Analog, E-979

Digital, E-979

Electronic/numerical analysis technique, E-835

IBM 650/computation methods, E-956

Ground wave calculations, E-907

Plane Earth programming, tested, E-907

Spherical Earth programming, tested, E-907

-To compute radio propagation data, E-379

-To compute vertical component of electronic field, E-924

Cross talk, calculation, E-663, 764

Detection of nuclear bursts in the air, E-1053

Differential method of measurement, E-653

Diffraction, calculation, E-19, 27, 300

Diffraction, loss, E-96

Diversity techniques, E-315, 500, 619, 680

Angle of diversity, E-680

Doppler tracking/measurement of range rate, E-1056

Dual polarization method, E-348

Electrical length variation measurement, E-301

Electrode array method, E-1027

Electronic land surveying, E-165

Equivalent gradient quantitative measurements, E-754

Facsimile measurement technique, E-15

Fading % expectancy over water, E-483

Field strength, calculation, E-48, 150

Calculation/field intensity, E-726

Calculation/field strength, E-131

Calculation/field/mixed paths, E-262

Calculation/ground wave field E-30, 80

CCIR's method of calculation, E-675

Field diffracted by a dielectric wedge, estimate, E-108

Graphical method of calculation, E-675

S/I for field calculation, E-1014

Flat radio mirror technique, E-911

FM methods, E-790

"Foliage" identification, E-1037

Frequency variation determination, E-829

Good path method, E-67

Graphical method, E-30

To calculate/field strength

To calculate/ray bending, E-853

To determine/dielectric constant and ground conductivity, E-983

Computation method/equivalent gradient, E-889

Design chart, carrier-to-noise calculation, E-349

Diagrams/effects on ground wave propagation, evaluation, E-631

Signal-to-noise determination, E-294

Hourly median transmission loss, estimate within monthly distribution, E-887

Interchannel modulation/prediction, E-967

Interference position of optical regions, E-675

Klystron, efficient operation technique, E-401

Knife edge method, E-217
XXX11

Large angle scattering of radio waves, E-873

Long term fading ranges, estimation technique, E-799

Magnetic tape storage of statistically fluctuating parameters, E-576

Magnetotelluric method, E-1027

Maximum likelyhood method, E-290

Meteorological parameter measurements, E-758

Methods and standards for compiling radio propagation indexes/meteorological

data, E-526

Microwave propagation survey techniques, E-395

Microwave techniques, E-221

Minimum required transmitter, calculation, E-809

Miniturization technique, E-749

Multiple scattering/solution, E-363

Noise, asymtomatic estimate, E-865

Numerical methods, E-42

Path antenna gain, evaluation, E-634

Path attenuation, calculation, E-500

Permittivity of air measurement, E-115

Phase difference method, E-69

Phase fluctuation, measurement, E-864

Point-to-point communication system performance, evaluation, E-615

Propagation, measurements, E-82

Propagation methods, E-67, 317

Punched cards

Data processing, E-1044

Indexing, E-460, 526

Radar methods, E-75, 204, 327, 533, 567, 580, 604, 605, 621, 688, 823,

1001, 1016, 1017, 1064, 1065, 1080

Used as altimeter/correction of errors, E-1017

Maximum range of radars, calculation, E-50

Radio methods, E-971

Derivation of K values from radio data, E-902

Radio soundings, E-123, 127, 140, 152, 194, 273, 281, 284, 347, 360,

418, 457, 497, 548, 621, 711, 741, 821, 838,

842, 879, 896, 969, 1016, 1033, 1059, 1084

Radio astronomical methods, E-544

Radio communication, forecasting, E-87

Radio meteorological investigations, E-88

Radio telephone methods, E-673

Ray alignment method including the negative equivalent of Earth's radius, E-811

Ray path curvature, correction, E-89

Ray tracing methods, E-604, 656, 688, 812

Recording methods, E-297

Reflection, E-96

Refraction

Calculation/super refraction, E-547

Computation/departure from normal method, E-822

Computation/exponential model, E-822

Computation/high angle method, E-822

Computation/initial gradient correction method, E-822

Computation/low angle method, E-822, 1079

Computation/statistical method, E-822

Compute refraction effects of radio waves, E-681

Corrective method/refraction errors/ E-1017

Data analysis method, E-961

Predict refraction of radio waves, E-698
XXX111

Refraction data and empirical method, comparison, E-47

S/I superrefraction distribution, E-1014

Solve stationary and non-stationary problem of coastal refraction, E-1006

Calculate dn wave refraction, E-633

Correction techniques, E-1012

Predict radio ray refraction, E-615

Refractive index

Calculation by Anderson's modified slide rule, E-862

CCIR's/field strength, E-675

Tabular method for calculation, E-94

To compute refractive index, E-222

To compute RF, E-278

To deduct refractive index profiles, E-105

To determine r. i. variation, E-150

To measure t index of refraction, E-158

To obtain true and modified index of refraction, E-153

To predict RI, E-595

Technique for radiosonde usage for direct RI measurements, E-711

Thermodynamic determination, E-399

To compute M curve, E-35

Used to analyze/reflection of radio waves, E-225

Used to predict UHF transmission, E-236

Computation, E-522

Refractometer soundings, E-285, 515, 581, 604, 622, 656, 917. 929, 951,

987, 1016, 1059, 1080

Scale model techniques, E-870

Scatter coefficient of terrain, calculation, E-830

Scatter communication techniques, E-1063, 1075

Scattered power, calculation, E-574

Scattering due to eddies/determination, E-937

Scattering of electromagnetic waves, calculation, E-676, 1043

Scattering problems, E-413

Scattering of sound waves, calculation, E-676

Shoran measurements, correction, E-89

S/I (Signal to noise intermodulation ratios), E-1011

S/I for field calculation, E-1014

S/I for homogeneous atmosphere, E-1014

S/I for inhomogeneous atmosphere, E-1014

S/I for superrefraction, E-1014

Signal fluctuation on range/prediction, E-38

Single side band techniques, UHF, E-401

Smooth perturbation method, E-949

Spaced corner reflector method, E-49

Spaced receiver method, E-485, 1058

Spectrum method, E-1005

Station coverage

Predict TV, E-370, 648, 745, 1078

Survey technique TV and radio ranges, E-467, 922, 1057
XXXIV

Statistical methods, E-382

Analysis/radio propagation data, E-379

For computing refraction of radio waves, E-822

Sampling procedures, E-297

For studying/distribution of scatterers, E-532, 533

Surface wave problems/solution, E-34

System loss evaluation, E-714

TV coverage methods, E-1103

Temperature

Turbulent fluctuations, recording, E-676

Theoretical techniques vs. prototype communication systems, E-932

Thin route technique, E-734

Tower sounding system technique, E-127

Transient noise measurement in a two-path communication system, E-858

Transmission characteristics of a given system, calculation, E-713

Transmission loss, prediction, E-658, 667

VHF and UHF communication forecast method, E-1057

Variation calculation method, E-415

Water vapor structure, investigations, E-525

Wave velocity, continuous measurements, E-257

Wind

Turbulent fluctuations, recording, E-676

Wind velocity, continuous measurements, E-257

Instruments

Phase generators, E-1060
XXXV

GEOGR APHICAL OUTLINE

A. HEMISPHERES AND REGIONS

1. Polar Regions

Polar Caps, E-753

Antarctic Seas, E-834

Dixson Island, E-1070

Arctic, E-517, 609, 1098

2. Tropical Regions, E-296, 609, 703

Equator, E-10

3. Temperate Zone, E-809

B. CONTINENTS

1. Africa

Equatorial Africa, E-716, 847

North Africa, E-214,928

West Africa, E-716

Algeria, E-762

Algiers, E-928, 1042, 1101

Bone, E-1042, 1101

Constantine, E-1042, 1101

Laghouat, E-759

Medea, E-759

Quargla, E-759

Setif, E-1042, 1101

Congo, Republic of the, E-847

Congo Basin, E-846

Guinea

Conakry, E-703

Nigeria

Niamey, E-754

Sahara, E-716, 762, 847

Senegal

Dakar, E-703

South Africa, Republic of

Durban, E- 148, 334

Natal Coast, E-115, 148

Wentworth, E-148

2. Asia

Bahrain Island, E-724

Bay of Bengal, E-460

India, E-860

Calcutta, E-438,679

Dum-Dum Airport, E-454,621

New Delhi, E-438, 925, 926

Northern India, E-931

Poona, E-438

Tirupati, E-879

3.

Israel

Lydda Airport, E-173

Japan, E-497, 735, 778

Hiraiso, E- 167, 263, 422

Hokkaido, E-951

Inubo, E-481,482

Izumi, E-311

Kanto District, E-339

Kanto Plain, E-777

Kawaguchi, E-311

Kokubunji, E-167, 263, 422, 481,

730

Mikuni Mountains, E-551

Mt. Yamizo, E-311

Nihonmatsu, E-730

Osaka, E-572

Sado, E-551

Sapporo, E-489

Sea of Kashima-nada, E-482, 524,

656, 690, 776

Tateno, E -263, 339

Tateno Aerological Observatory, E-639

Tokyo, E-270, 551, 572

Toyama Bay Coastal Region, E-163

Tsukuba, E-339

Jordan, E-734

Lebanon

Beirut, E-734

New Guinea, E-1069

Persian Gulf, E-460, 548, 724

Q uatar

Doha, E-724

Saudi Arabia, E-734

South China Sea, E-460

Syria, E-734

Turkey, E-920

Australasia

Australia, E-249,820

Coastal regions, E-61

New Madden-Bowral air route,

E-215

Sydney-Melbourne air route, E-215

Sydney-New Madden air route,

E-215

West Coast Region, E-61

New South Wales

Bowral-Goulbum air route,

E-215
XXXVI

South Australia

Mt. Bonython, E-483

Yorketown, E-483

Victoria

Arthur's Seat, E-483

Melbourne, E-483

New Zealand, E-87. 145, 166, 483

Canterbury, E-73,88

Canterbury Bight, E-112

South Island, E-112, 145

Europe, E-820

Central Europe, E-155, 310, 392

Western Europe, E-85, 155, 716

Austria

Vienna, E-978

Baltic Region, E-172, 310

See also under Democratic Republic (East Germany)

Belgium

Liege, E-846

Uccle, E-396,842,930,999

British Isles, E-840

British West Coast, E-183, 184

Ireland

Clifden, E-7

United Kingdom, E-145, 325, 332,

483, 559, 578, 582,

936

Great Britain, E-87

Great Britain Coast, E-83

England, E-45, 307, 487, 818,

942, 958

Bromley, E-941

Cambridge, E-189

Cardington, E-174

Catterick, E-941

Chelmsford, E-1040

Clacton on Sea, E-114

Devon, E-587, 722, 1040

Star Point, E-1110

Dunstable Downs, E-1072

Essex, E-1040, 1110

Galleywood, E-1040

Lerwick, E-418

Lewes, E-408

Littlehampton, E-408

London, E-7

Middlesex, E-722

Pevensey, E-408

Plymouth, E-587

Portsmouth, E-565

Slough, E-176, 1107

Star Point, E-523

Wembley, E-523. 722

Witnesham (Suffolk), E-722

Worthing, E-408

Wrotham, E-231,418

Scotland, E-487

Loch Goil, E-208

Shetland Islands. E-487

Wales

Cardigan Bay, E-107, 183,

184

C zechoslovakia

Prague, E-700

Denmark, E-1058

Copenhagen, E-471

English Channel, E-565

France, E-214, 716, 928, 936

Bagneux, E-231

Caen, E-689, 717

Cholet, E-952

LaPunta (Corsica), E-409

Mt. Agel, E-409

Nancay, E-1042, 1101

Orsay, E-952

Paris, E-114, 689, 717, 1042,

1101

Toulouse, E-367

Germany (general and undetermined), E-325,887

Berlin, E-247, 567

Central Germany, E-324

Democratic Republic (East

Germany), E-583

Baltic Region, E-310

Dresden, E-700

East Berlin, E-700

Fichtelberg, E-700

Harr, E-247

Inselberg, E-700

Kuhlungsborn, E-172, 254

Federal Republic (West Germany), E-138,912

Hamburg, E-347

Hannover, E-347

Northwest Germany, E-151

Quickborn, E-128

Schleswig, E-347

Greece

Crete, E-521,874

Thera (island), E-521,874
XXXV11

Italy, E-327

Carloforte Observatory (Sardinia), E-530

Elmas Observatory, E-530

Rome, E-554

Santa Margherita Ligure,

E -36 1,554

Sardinia, E-364, 530

Tyrrhenian Coast, E-361

Netherlands

den Helder, E-818

Domburg, E-318

Scheveningen, E-487

North Sea, E-487, 818

Norway, E- 743, 920

Bodo, E-920

Oslo, E-920

Poland

Kolberg, E -474, 700

Spain

Majorca (Balearic Islands),

E-928

Minorca (Balearic Islands),

E-364, 530

Mahon Observatory, E-530

Sweden, E-702

U.S.S.R., E -455, 505, 575

Moscow, E-1070

North America, E-174, 175, 281, 808,

820

Canada, E-87, 250

Central Canada, E-299

Northwest Canada, E-402

Alberta

Suffield, E-49

Newfoundland, E-280,398

Goose Bay (Labrador), E-650

Labrador, E-650

Ontario, E-636

Ottawa, E-637

Quebec

Northern Q uebec , E-650

Schefferville, E-650

Caribbean Region, E-328,941

Caribbean Sea, E-91

West Indies, E-87

Antigua, E-87

Bahama Islands, E-673

Nassau, E-873

New Providence Island,

E-897

Cuba

Guanabo, E-816

Havana, E-873

Jaruco, E-751

Gulf of Mexico, E-120, 187

Lake Ontario, E-204

United States, E-186, 194, 236,

253,273,325,457,

483, 673, 694, 729,

840,887,895

Central Plains, E-641

Great Lakes, E-10, 977

East Coast, E-241, 285

Middle West, E-135,437

Northeastern United States

Coastal Regions,

E-283

Northern plains, E-841

Northern States, E-284

Pacific Coast Region

San Nicolas Island, E-1046

Rocky Mountains, E-235

See also under Colorado

West Coast, E-241, 285

Alaska, E-402

Aleutian Islands, E-402

Barrow, E-774

Bethel, E-123

Fairbanks, E-123

Arizona, E -340, 674

Fort Huachuca, E-365

Gila Bend, E-59

Sentinel, E-59

Tucson, E-369

Yuma, E-369

California, E-881

California Coast, E-402

Golden Gate Channel, E-444

La Jolla, E-377

Los Angeles Coastal Areas,

E-385

Los Angeles Basin, E-546

Point Mugu, E-1046

San Diego, E-53,87,378,

897, 1074

San Francisco, E-953

San Pedro, E-378

Southern California, E-851,

852

Southern California Coast,

E-360,798,823
XXXV111

Colorado, E-185, 374, 881

Boulder, E-207, 526, 677,

780, 1044, 1066,

1081,1098, 1104

Cheyenne Mountains, E-237,

271,288,304,305,

1044, 1045

Denver, E-10, 369

Eastern Colorado, E-798,

965

Fort Carson, E-288

Pikes Peak, E-308

Rocky Mountain Region,

E-391

District of Columbia (Washington), E-125, 175,

256, 390

Florida, E-374

Cape Kennedy (Cape Canaveral), E-897

Florida City, E-816

Key Marathon, E-751

Key West, E-218

Miami, E-218, 442, 673

Hawaii, E-1074

Honolulu, E-953

Maui, E-780

Illinois, E-437

Dearborn, E-222

Joliet, E-222, 284

Lake Michigan, E-222

Quincy, E-304, 736

Rantoul, E-369

Iowa

Cedar Rapids, E-304, 375,

448, 517, 736

Kansas, E-271, 1044

Maine

Mt. Desert Island, E-31

Maryland

Baltimore, E-390

Massachusetts

Blue Hill, E-29

Boston, E-116, 179, 267, 326

Ft. Banks, E-369

Massachusetts Bay, E-40, 87

Needham, E-52, 116

New Bedford Coastal Area,

E-539

Round Hill, E-404, 616, 619,

815

Scituate, E-268

South Dartmouth, E-517

Michigan

Mt. Clements, E-369

Missouri

Lamar, E-375

New Jersey, E-160

Alpine, E-116, 815

Crawford's Hill, E-616,619

Lakehurst, E-196

Nutley, E -350, 351

Sea Bright, E-24

New Mexico, E-674

Tularosa Basin, E-803

White Sands, E -604, 688

New York, E-57, 111

Albany, E-284

Bedford, E-802

Buffalo, E-312,871

Coney Island, E-10

Hauppage, E-179

Ithaca, E-312

Long Island, E-274

New York City, E-268

Riverhead (Long Island),

E-179, 233

Southampton (Long Island),

E-350, 351

Wethersfield Springs, E-312

Wilson, E-802

North Dakota

Bismarck, E-442

Pennsylvania

Pittsburgh, E-22, 257, 284

Ohio

Dayton, E-146, 196

Southern Ohio, E-241

Southwest Ohio, E-197

Toledo, E-284

Wright -Patters on Air Force

Base, E-132

Texas, E-101, 159,958

Austin, E-206,264

Corpus Christi, E-69

Dallas, E-206

Houston, E-549

Lake Austin, E-419

Midland, E-549

San Antonio, E-206, 549

Virginia

Richmond, E-256

Sterling, E-448
XXXIX

Washington

Tatoosh Island, E-442

Washington West Coast,

E-197

West Virginia

Morgantown, E-13, 222-29

6. South America

Brazil, E-861

Chile, E-898

C. OCEANS, SEAS and ISLANDS

1. Atlantic Ocean

North Atlantic, E-10, 267, 326

West Atlantic, E-194

Ascension Island (St. Helena),

E-869

Iceland, E-S09

2. Mediterranean Region, E-296

Mediterranean Sea, E-l, 530, 554

Eastern Mediterranean Sea,

E-460

Western Mediterranean Sea,

E-716

3. Pacific Ocean, E-197, 385

North Pacific, E-879

Northwest Pacific, E-269

Tropical Western Pacific, E-35

Western Pacific, E-819

Hawaii, see under United States

Nansei-shoto Islands (Ryukyu

Islands), E-921

4. Red Sea, E-156

BIBLIOGRAPHY ON PROPAGATION OF RADIO WAVES

THROUGH THE TROPOSPHERE

1902

E-l Jackson, H.B. , On some phenomena affecting the transmission of electric waves

over the surface of the sea and earth. Royal Society of London, Proceedings,

70(462): 254-272, July 8, 1902. 8 figs. , 4 tables, ref. DLC--A pioneer study

based on observations made from Naval vessels in the Mediterranean between

1895 and 1902. The effects of topography on radio transmission over land and

sea and the reduction in distance of transmission caused by dust or salt particles

in the atmosphere are first discussed. The conclusions regarding sferics are: they are more frequent in summer and autumn than in winter or spring, in mountainous regions than over open sea, in southerly than in northerly winds, in front

of cyclone than in rear, with falling barometer than rising and (except for storm

conditions) at 8-10 p. m. than between 9 a. m. and 1 p. m. A gale without lightning was preceded by sferics. It was noted that sferics produced signals in tape

recorders similar to actual Morse code letters, so records of sferics were made

possible by leaving the recorders operating. During approaching storms the

radio reception distance was reduced 30-80% but during passage of sferics producing storm the reception distance would usually increase tremendously in

spite of the frequent discharges. During sirocco winds the reception distance

was markedly reduced. The author also noted effects such as skipping or zones

of inaudibility of 20-40 mi and the remarkable fact that by using other transmission wave lengths the skipping did not occur. Thus he correctly interprets effects

of lightning but not of tropospheric ducts or ionospheric reflection. (Met. Abs.

4K-5)--M.R.

1903

E-2 MacDonald, H.M., The bending of electric waves round a conducting obstacle. Royal Society of London, Proceedings, Ser. A, 71(472) :251-258, 1903. Table,

6 foot-refs. , 4 eqs. Comments by Lord J. W.S. Rayleigh and H.Pointcare, Ibid. , 72(477) :40-52, 1904. Eqs. Reply by MacDonald, Ibid., 72(477) -.59-68, 1904.

Eqs. DLC--Assumes a Hertzian oscillator located outside a perfectly conducting sphere, in order to study theoretically the behavior of electric waves incident to the sphere. Some applications to the propagation of waves along the

different surfaces of the Earth are discussed. (See ref. E-5)--W. N.

1907

E-3 Zenneck, J. , Uber die Fortpflantzunq ebener elektromagnetischer Wellen lanqs

einer ebenenen Leiterflache und ihre Beziehunq zur drahtlosen Telegraphie.

(Propagation of plain electromagnetic waves along a smooth conducting surface

and its relation to wireless telegraphy.) Annalen der Physik, Ser. 4, 23(10):

846-866, 1907. 11 figs. , foot-refs., 10 eqs. DLC -Starting with the directional

transmission equation, the problem is discussed in terms of direction of the electric field, wave absorption in the direction of propagation, wave absorption by

penetration into the conductor, state and propagation velocity of the electric and

magnetic field intensity. The last part of the discussion is devoted to application of the results obtained to wireless telegraphy, taking into consideration

ground and atmospheric conditions. --W. N.
1909

// E-4 Sommerfield, A. , Uber die Ausbreitung der Wellen in der drahtlosen Telegraphie.

(Wave propagation in wireless telegraphy. ) Annalen der Physik, Ser. 4, 28(4):

665-736, 1909. 8 figs. , footnote refs. , 65 eqs. DLC--The purpose of this theoretical discussion is to prove the existence of the ground wave and to differentiate between the sky wave and the former, whose propagation and behavior over

the Earth, under different conditions, is discussed. --W. N.

1911

E-5 MacDonald, H. M. , The diffraction of waves round a perfectly reflecting obstacle. Royal Society of London, Philosophical Transactions, Ser. A, 210:113-

144, Feb. 1911. 2 figs. , table, foot-refs. , eqs. DLC- -An attempt "to find the

effect at all points produced by a Hertzian oscillator placed outside a conducting

sphere, whose radius is large compared with the wavelength of the oscillations".

(See ref. E-2)-From text.

E-6 Nicholson, M.A. , On the bending of electric waves round the earth. Pt. 1. Philosophical Magazine, London, 6th ser. , 19(110) :276-278, Feb. 1910. Footrefs. , 43 eqs. Pt. 2—4 have title On the bending of electric waves round a large

sphere . Pt. 2, Ibid., 20(115): 157-172, July 1910. Foot-refs., 57 eqs. Pt. 3,

Ibid., 21(121):62-68, Jan. 1911. Stables, foot-refs., 7 eqs. Pt. 4, 21(123):

281-295, March 1911. Foot-refs. , 45 eqs. DLC--Critisizes Poincare's results,

then examines "the extent of the region between brightness and shadow when a

radial oscillator is placed close to the surface of a perfectly conducting sphere".

Pt. 2 deals with the nature of the transitional region and in Pt. 3 author determines O , the numerical coefficient to establish the intensity at any surface

point. Since it is improbable that the estimated ratio lO"*2 (if diffraction alone were the agent) could be recorded by any existing receiver, it is suggested that

atmospheric layers reflect the transmitted energy back to the Earth's surface.

Pt. 4 is an attempt to determine a higher approximation valid for points within

"the region of brightness". --W. N.

1912

E-7 Eccles, W.H. , On the diurnal variations of the electric waves occurring in

nature, and on the propagation of electric waves round the bend of the Earth.

Royal Society of London, Proceedings, Ser. A, 87(592): 79-99, July 1912. 9 figs.,

refs. in foot notes. DLC--Discusses the influence of "strays" (i. e. , sferics) and

other twilight effects on propagation of wireless waves. Ionic refraction causes

bending of radio waves around the Earth's surface. The observational results of

signal transmission, Clifden-London, Jan. 1912, presented in curves, are indicative of the theory. --W. N.

E-8 March, H. W. , Uber die Ausbreitunq der Wellen der drahtlosen Telegraphie auf

der Erdkuqel. (Propagation of radio waves over the terrestrial globe. ) Annalen

der Physik, Ser. 4, 37(l):29-50, 1912. 3 figs. , foot-refs., 54 eqs. DLC--

This excerpt of author's dissertation explains the results of overcoming the

earth's curvature in radio communication. The first part of the paper gives the

general integral solution and in the second part is the integral solution discussed

in the case of complete conduction. --W. N.
1914

E-9 Macdonald, H. M. , The transmission of electric waves around the Earth's surface.

Royal Society of London, Proceedings, Ser. A, 90(615) -.50-61, April 1914. Table,

refs. in footnotes, eqs. DLC--A series is obtained which represents the magnetic

force at any point on the surface when the oscillator is also on the surface. Calculations of fall in amplitude with increased distance are shown for different wave

lengths in the table presented. (See ref. E-5 and E-2)--From text.

E-10 Marriott, Robert H. , Radio range variation. Institute of Radio Engineers, N. Y.,

Proceedings, 2(l):37-58, March 1914. 4 charts. Discussion p. 53-58. Ref.

DLC --Discussion of statistical results (shown on very detailed charts) of experiments with distance of radio reception between ships at sea off Coney Island, in

the Great Lakes, etc. , and in the Denver, Colo, area as related to "atmospherics"

temperature, humidity, vapor pressure, dew point, moonlight, daylight, etc. Atmospherics were related to temperature, being stronger in afternoon and in summer. The seasonal vapor pressure curve proved to be the inverse curve of distance of reception (vapor pressure in inches X 10) to the 5th power gave an index

of strength of atmospherics above audibility. The question of whether the action

of v. p. was in refracting, reflecting or absorbing power of the atmosphere at the

station or between stations was not resolved. In the discussion Austin Curtis

remarks on effect of local charges in thunder- or snow-storms on "noise" and on

the "distant" effect of numerous lightning storms in the equatorial belt of calms

which moves N and S with the sun. Thus in the northern summer sferics are al- most constant in the North Atlantic, whereas in winter, when the belt is south of

the equator, the radio reception is vastly improved. Julius Weinberger remarks on Kiebitz's paper discussing calculations of refractive index for moist air and

the consequent bending of emission waves toward the earth. John Stone remarks on the ionizing effect of sunlight in upper atmosphere and consequences for radio

propagation. Dr. De Forest remarks on reflecting layers of heated air reported by

Tyndall and on similar reflecting of em waves. George H.Clark remarks on effect

of a thunderstorm area between stations in cutting down signals until after it had

passed the second station, when signals improved markedly. (Met. Abs. 4K-12)

--M.R.

1915

E-ll Love, A.E.H. , The transmission of electrical waves over the surface of the

Earth. Royal Society of London, Philosophical Transactions, Ser. A, 215:105-

131, 1915. 4 figs. , 4 tables, 18 refs. , 56 eqs. DLC--The question of how

radio waves penetrate the shadow region is critically surveyed. The purpose is to determine the electric and magnetic forces in the dielectric at points near

the surface, but not near the sender, assuming the earth is a homogenous con- ductor in homogenous dielectric and the separating surface being a perfect

sphere. The results, as far as daylight observations are concerned, appear

to favor the diffraction theory although some other unaccounted forces are active,

particularly at night. --W. N.

1927

E-12 Pedersen, Peder Oluf, Propagation of radio waves along the surface of the earth

and in the atmosphere . Ingenio'rvidenskabelige Skrifter, Ser. A, 15 a, Copenhagen (issued by Danmarks Naturvidenskabelige Samfund udgivet ved Udvalget

for Ingenio'rvidenskabelige Forskning) , 1927. 244 p. Numerous figs. , 11 tables,

foot -refs. , eqs. Also: Appendix, Ibid. , 15 b, 1927. 19 p. Figs. DLC--
This is a pioneer text covering all the known theory and empirical knowledge of

radio propagation in the troposphere and ionosphere. The physical and chemical

properties of the atmosphere are discussed and illustrated with models and diagrams. Optical, as well as electrical properties, are considered. Effects of

solar radiation and corpuscular emissions and ionization of rarified gasses, ef- fects of wind, pressure, mean free path, number of collisions, lifetime of free

electrons, recombination, cosmic rays, auroras, discontinuities, sunrise and

sunset, wavelength, magnetic fields, etc., are discussed. (Met. Abs. 8 1-1)

-M.R.

1929

E-13 Colwell, R.C., Fading curves and weather conditions. Institute of Radio Engineers, N. Y. , Proceedings, 17(1): 143-148, Jan. 1929. 11 figs. DLC -Brief re- port on observations at Morgantown with a Shaw recorder of station KDKA, AprilMay 1927. The sunset fading curves on fine days were more irregular than those on cloudy days. The signal strength was stronger in daylight hours. A falling curve indicated clearing weather and a rising curve cloudy weather or rain next

day. (See ref. E-22). (Met. Abs. 8I-2)-W. N.

1931

E-14 Parkinson, T. ; Kirby, S.S.; Arnold, P. N. et al. , Bibliography on radio wave

phenomena and measurement of radio field intensity. Institute of Radio Engineers, Proceedings, 19(6): 1034-1084, June 1931. DLC -The bibliography contains 630 annotated entries classified under subject and related subdivisions in

chronological order: radiation, radio wave phenomena, fading, daily and sea- sonal variations, direction variations; meteorological, geophysical and cosmic

effects; eclipses, reflection, refraction, diffraction, absorption, polarization,

K-H layer, wave front angle, transmission formulas, atmospheric disturbances,

strays, directional properties, etc. (Met. Abs. 8I-4)--W. N.

1932

E-15 Eckersley, T.L. , Studies in radio transmission. Institution of Electrical Engineers, London, Journal, 71(429) :405-459, 1932. 33 figs. , 7 tables, numerous

refs. , 109 eqs. DLC --With the advent of short wave telegraphy, a new technique of echo and facsimile measurement has been developed, facilitating signal

intensity measurements in the wavelength range between 14 and 50 m. Pt. 1 of

this paper deals with the adopted method of making facsimile measurements, and

describes the results obtained, while in Pt. 2, the author discusses transmission

problems in the light of these data and suggests the theoretical methods to be

employed in solving such problems. Pt. 3 discusses the problem of scattering

while in Pt.4, the author deals with theory. --Author's abstract.

E-16 Marconi, Guglielmo, Radio communication by means of very short electrical waves. Royal Institution of Great Britain, Proceedings, 27(130): 509-544, Dec.

1932. 10 figs. , ref. DLC --Author describes construction and features of improved transmitters and receivers, methods used and results achieved, such as "beyond horizon" communication at 600,000 kc. This lecture, given before the

Royal Institution Dec. 2, 1932, was accompanied by schematic diagrams and

photographs which are reproduced here. (Met. Abs. 8I-5)--W. N.
1933

E-17 Schelleng, J.C.; Burrows, C.R.and Ferrell, E.B. , Ultra short wave propagation. Institute of Radio Engineers, N. Y. , Proceedings, 21(3):427-463, March 1933.

IS figs. , 2 tables, numerous refs. , 15 eqs. DLC--Pt. I contains some results of an experimental study of USW propagation in order to obtain quantitative data for the theoretical work in Pt. II where author analyzes experimental results in comparison with current theory. Such topics as reflection, diffraction and refraction

are treated in relation to optical and nonoptical sea and land paths. Some characteristics of frequencies as a function of topography are considered. (Met.

Abs. 8 1-6) -W.N.

1935

E-18 Burrows, Charles R. ; Decino, Alfred and Hund, Loyd E. , Ultra-short-wave propagation over land . Institute of Radio Engineers, N. Y. , Proceedings, 23(12):

1507-1535, Dec. 1935. 21 figs. , 11 tables, numerous refs. , 25 eqs. DLC--

Frequency characteristics at 100-200 Mc are discussed. Experimental confirmation both for an optical and nonoptical path involved in the approximate theory

given, was established, and discrepancies between theoretical and practical

results indicate absence in the formula of some element important to this propagation. (Met. Abs. 8I-7)-W. N.

1936

E-19 Handel, Paul von and Pfister, Wolfgang (Deutsche Versuchsanstalt f. Luftfahrt,

Berlin) , Die Ausbreitunq der ultrakurzen Wellen (cm-, dm-. m-Wellen) langs der

gekrummten Erdoberflache. (Propagation of ultrashort waves (cm, dm and m

waves ) along the curved surface of the earth. ) Hochfrequenztechnik und Elektroakustik, Munich, 47(6): 182-190, June 1936. 20 figs. , 14 refs. , eqs. DLC--

USW propagation into the region beyond the horizon is dependent on diffraction

and refraction. On the basis of optical analogy, diffraction is calculated by

different methods. Calculations based on radiation received beyond the optical

horizon are found to yield the best agreement with measurements. For practical use of the results, curves are presented which give values of iield strength as

a function of distance and altitude for all pertinent frequencies. The curves have been verified in flight. Measurements concerning the influence of refraction have been added. (See ref. E-27)--Transl. of Authors' abstract.

1937

E-20 Colwell, R.C. and Friend, A. W. (West Va. Univ. , Dept. of Phys. ), Tropospheric

radio wave reflections. Science, Wash. ,D.C, 86(2238): 473-474, Nov. 9, 1937.

Fig. , table, foot-refs. --During a brilliant auroral display tropospheric reflection

from less than 1 km height was observed. The reflection was split into two parts.

Details of the observation are presented in a table and the cathode ray oscillograph pattern is given. --G.T.

E-21 Friend, A. W. and Colwell, R.C, Measuring the reflection regions in the troposphere. Institute of Radio Engineers, N. Y. , Proceedings, 25(12):1531-1541, Dec.

1937. 10 figs. , 7 refs. DLC--The modified radio equipment at frequencies of

1614, 2398 and 3492. 5 kc is graphically outlined. The equipment permitted determination of several stratified layers at 1-12 km altitude. It is suggested that

the reduced velocities of waves, (as much as 50-85% that of the velocity in

vacuum) observed over a 15 mi distance, are controlled by the reflecting lower

atmosphere. (Met. Abs. 8I-9)--W. N.
1938

E-22 Colwell, R. C. and Friend, A. W. , Studies of tropospheric changes and radio

reception . American Meteorological Society, Bulletin, 19(7):317-319, Sept.

1938. Fig. , 9 refs. DLC --Forecasting weather conditions one day ahead was

done with 80% accuracy using the KDKA station signals, intensity of which

was found to depend upon tropospheric layers (also designated as the C-region).

Inversion conditions generally affect radio wave propagation and a cold front

was always linked to a lower tropospheric reflectivity. The observations were made at W. Virginia Univ. , Morgantown, about 100 km south of the KDKA

radio station in Pittsburgh, Pa. (See ref. E-13) (Met. Abs. 8I-10)--W. N.

E-23 Englund, Carl Robert; Crawford, A.B. and Mumford, W. W. , Ultra-short-wave

transmission and atmospheric irregularities. Bell System Technical Journal,

17(4):489-519, Oct. 1938. 19 figs. , tables, 13 refs. DLC -Mechanism of

fading of 1. 6 to 5. meter waves over a 70 mi ocean path was studied 106 days

over a 2 yr period. Both horizontal and vertical polarization were used; when

on different wavelengths, the shorter wave faded more. Presence of multiple

signal components along the earth's surface are calculable (cf. WWEDENSKY, VAN DER POL and GRAY), these, and one or more air-mass-reflected components, may encompass the explanation for fading mechanism. Amplitude

changes up to 40 db and fading rates up to 5 fades per minute were observed.

Reflecting boundaries from 5. 5 km down to 1. 9 km were measured and lower ones are indicated. (Met. Abs. 8I-12)--W. N.

E-24 Englund, Carl Robert; Crawford, A.B. and Mumford, W. W. , Ultra-short-wave

radio transmission through the nonhomogeneous troposphere . American Meteorological Society, Bulletin, 19(8) -.356-360, Oct. 1938. 4 figs. , 4 refs. , eq.

DLC —This is the first experimental proof of boundaries and layers as controlling

tropospheric radio wave propagation, multiple paths of which is a function of

discontinuities. The observations were conducted in the fall of 1933 from a simple surface station at Sea Bright, N.J. , and over a 15 to 120 mi path to an

aircraft at 1000-8000 ft altitude using 4. 6 m and 1. 58 m wavelengths. Experimental approach, results obtained and conclusions are given briefly. (Met.

Abs. 8I-1D-W. N.

1939

E-25 Friend, A. W. and Colwell, R.C., The heights of the reflecting regions in the

troposphere . Institute of Radio Engineers, N. Y. , Proceedings, 27(10): 626-634,

Oct. 1939. 10 figs. , 10 tables, 16 refs. DLC -This discussion is on the so- called C regions, a tropospheric layer at about 1.8 km but characterized by

variation of altitude with change in weather, influenced perhaps by solar activity.

The discovery of this region was made in the summer of 1938. The tropospheric

reflection occurs generally below 2. km as a function of discontinuities, the

reflection coefficient being about 10-3 to 10*5. (Met. Abs. 8I-13)--W. N.

E-26 Maclean, K. G. and Wickizer, G.S., Notes on the random fading of 50 megacycle

signals over nonoptical paths. Institute of Radio Engineers, N. Y. , Proceedings,

27(8):501-506, Aug. 1939. 12 figs. , 2 tables, 8 refs. --To obtain data on the

variation of field strength beyond the horizon, simultaneous recordings were made

at 3 locations, one within the optical path of the transmitter, one 700 ft below the

line of sight, and one 11,400 ft below the line of sight. All three locations were
on the same line from the transmitter. Recordings extended over a two week

period, chosen at a time when atmospheric refraction was likely to be favorable.

Analysis of the recorded data indicates several things of interest. The variation

of field strength at each location was random and showed no correlation with any

other location; the range of field strength variation exceeded 49 decibels at the

most remote location, maximum fields generally occurred at night, and previous

data on the rate of attenuation beyond the horizon were confirmed. --Authors'

abstract.

Millington, G. , The diffraction of wireless waves around the earth. (A sum- mary of the diffraction analysis with a comparison between the various methods).

Philosophical Magazine, London, 27(184): 517-542, May 1939. 3 figs. , 4 refs. , 10 eqs. --The three independent methods (B. Vvedenskii; B. van der Pol and H.Bremmer; T.L. Eckersley and G. Millington) which try to answer the problem of the

diffraction of wireless waves around the Earth are compared with the purpose to show that the differences involved are only a question of the approximations made

in deriving the results, and that with one exception, they are not of any practical

significance. (See ref. E-19)--E. K.

1940

Colwell, R.C. , The troposphere and radio waves. Institute of Radio Engineers,

N. Y. , Proceedings, 28(6): 299-302, June 1940. Fig., table, 8 refs. , 3 eqs.

DLC--The influence of weather on long and short waves is theoretically explained

by changing cyclones and anticyclones that vary the height and the reflecting

power of the inversion discontinuities. (Met. Abs. 8I-14)--W. N.

Friend, Albert W. , Developments in meteorological sounding by radio waves.

Journal of the Aeronautical Sciences, 7(8):347-350, June 1940. 6 figs. , table,

3 refs. Discussion by Harry Diamond, Ibid. , p. 350-351, and Reply by Friend,

Ibid. , p. 351-352. DLC --During late fall of 1939 experimental storm observations were made by West Virginia University with the aid of transmitted and reflected

radio waves, and compared with the Blue Hill Observatory radiosonde data and

aircraft data. The results, presented in curves, show good agreement.

1941

Norton, K. A. , The calculation of ground wave field intensity over a finitely

conducting spherical earth. Institute of Radio Engineers, N. Y. , Proceedings,

29(12): 623-639, Dec. 1941. 16 figs. , 10 tables, numerous refs. , 60 eqs.

DLC --Earlier and present theoretical knowledge is here summarized into graphical

methods along with equations so as to facilitate the work of calculation under

discussion. (Met. Abs. 8I-16)»W. N.

Selvidge, H. , Diffraction measurements at ultra-high frequencies . Institute of

Radio Engineers, N. Y. , Proceedings, 29(1):10-16, Jan. 1941. 12 figs. , 7 refs. , eq. DLC —A successful attempt to measure the diffraction alone was conducted

over the natural knife edge of Mount Cadillac (1532 f. a. s. ) of Mount Desert

Island on the Atlantic coast near Harbor, Maine. The results of the tests at 55

and 110 Mc are presented in curves showing good agreement with theory.

Horizontally polarized waves were diffracted more than the vertical. (Met.

Abs. 81-17)-- W.N.
8

1942

E-32 McPetrie, J.S.and Saxton, J. A. , Diffraction of ultrashort radio waves . Nature,

London, 150(3801): 292, Sept. 5, 1942. 2 figs. , table, 3 refs. --Authors pointed

out earlier that ultra short radio waves polarized with electric vector vertical are propagated into the shadow of hills more readily than horizontally polarized waves.

Results of experiments are presented and discussed in which they observed the

opposite effect for receiver positions beyond hills but just outside the shadow.

--E.K.

1944

E-33 Katz, Isadore and Austin, J. M. , Qualitative survey of meteorological factors

affecting microwave propagation . Massachusetts Institute of Technology. Radiation Laboratory, Report No. 488, June 1, 1944. 50 p. 17 figs. , 14 tables, 13

refs. MCM--An introduction to radio meteorology, stressing the forecasting of

the distribution of the modified index of refraction. Dependence of modified index curve on vapor pressure and temperature gradient is discussed. The types of

index curves, which are classified into six categories, are discussed in detail.

(Met. Abs. 2H-16)

E-34 Leontovich, M. , Ob odnom metode resheniia zadach o rasprostranenii elektromagnitnykh voln vdol' poverkhnosti zemli . (A method of solving problems of

electromagnetic wave propagation along the Earth's surface.) Akademiia Nauk

SSSR, Izvestiia, Ser. Fiz. , 8(l):16-22, 1944. Refs., 19 eqs. DLC- -The problem of electromagnetic wave propagation from a vertical dipole situated near the

surface of a plane conducting earth is reduced to the solution of a differential

equation of parabolic type with defined limiting conditions. The method may be

extended to cases of variable ground conductivity and of electromagnetic wave

propagation over a spherical earth. --G.T.

E-35 Smith, Dillon E. ; Fletcher, Robert D. et al. , Tropospheric weather factors likely

to affect superrefraction of VHF-SHF radio propagation as applied to the Tropical

Western Pacific. U.S. Weather Bureau, Report RP-1, July 1, 1944. 100 p. 53

figs. , eqs. append. DWB--Meteorological characteristics of the tropical western

Pacific, including the East Indies, are presented in this preliminary report as a guide to the radar meteorologist engaged in forecasting the atmospherically modified index of refraction, M curve. Meteorological characteristics of the area are discussed first, followed by general discussion of various types of normal inversions in the atmosphere and their associated modified refractive index. The meteorological factors which disrupt normal inversions are taken up. Finally, basic re- lations between weather factors and modified index curves noted. Methods of computing the M curve from aerological low level sounding data are presented. In general, theoretical aspects of the whole problem are not investigated. Numerous

meteorological charts and diagrams are included. (Met. Abs. 81-20)

E-36 Treloar, H. M. , Radar meteorological report—probable radar ducts in September

in region including north Australia and islands to the north and some general matters. Australia. Meteorological Services, Research Report, Ser. 10, No. 20,

1944. 21 p. 5 fold, charts, tables. DWB--Author considers the classes, distribution and intensity of warm, dry winds moving out over the sea and the heights

of the resultant radar ducts. He states that in such air streams combined rapid

vertical fall of humidity and some vertical increase of temperature make long range

reception possible. His research is theoretical, and results tentative, but of use

to practical researchers in this region. (Met. Abs. 8 1-19) --H. P. Kramer.
1945

Friend, Albert W. , A summary and interpretation of ultra high frequency wave

propagation data collected by the late Ross A.Hull. Institute of Radio Engineers,

N. Y. , Proceedings, 33(6) -.358-373. June 1945. 24 figs. , 5 refs. , eq. --An analysis of portions of data recorded by Hull on the propagation of 60 megacycle waves

indicates that, with certain extensions and minor variations, his theories were

leading toward the now apparently correct solution of the ultra high frequency propagation problems. It was indicated that propagation far beyond the horizon was

produced by refraction or reflection in the tropospheric strata. Calculations of

radius of ray curvature have been made from data provided by the U.S. Weather

Bureau, from stations near the propagation terminal points. It is indicated that

radii of curvature less than the radius of the Earth are coincident with conditions

favorable to the propagation of strong signals over this path extending far beyond

the horizon. It is concluded that more accurate meteorological data with finer

structure characteristics should make possible more precise calculation of propagation conditions. It also appears that certain meteorological conditions may

be assumed when various propagation conditions are encountered. --Author's

abstract.

1946

Bergmann, Peter G. , Propagation of radiation in a medium with random inhomogeneities . Physical Reviews, N. Y. , 70(7/8): 486-492, Oct. 1946. 4 figs. , 63 eqs.

DLC--It is shown how approximate formulas, derived from geometrical optics,

correlate statistical properties of inhomogeneities with fluctuations in signal

level, and how a simplification of the formulas permits prediction of signal fluctuations dependent on range. (Met. Abs. 8 1-21) —W. N.

Booker, H.G. , Elements of radio meteorology: how weather and climate cause

unorthodox radar vision beyond the geometrical horizon . Institution of Electrical

Engineers, London, Journal, Pt. IIIA, 93(l):69-78, 1946. 13 figs. DLC--The

object of this paper is to describe in broad outline the phenomenon of radio re- fraction in the lower atmosphere and to present the interdependence of radio propagation and meteorology in such a way that its implications for radio engineers

are brought to light. Some examples of unorthodox radar vision; the ray theory

and wave theory in connection with radio ducts; the meteorological requirements

for super-refraction; the weather conditions involving super-refraction; and the

climatic conditions involving super-refraction are discussed in detail. --E. K.

Craig, Richard A. , Measurements of temperature and humidity in the lowest

1000 ft of the atmosphere over Massachusetts Bay. Papers in Physical Oceanography and Meteorology, Cambridge, Mass. , 10(1), Nov. 1946. 47 p. 54 figs. , 11 refs. DWB--There is a wealth of information in this exemplary presentation of

temperature and humidity profiles. Of 500 aircraft soundings made over Massachusetts Bay in the summer and fall of 1944, 51 were selected which represent

a wide variety of conditions for radio wave propagation. Profiles of temperature,

dew point, and associated refractive index, based on psychrometric measurements

at 50, 100, 150, 200, 300. . .and 1000 ft above the water surface, are shown for each of the 51 ascents, along with an analysis of the curves and a detailed sum- mary of the synoptic situation. In the majority of cases, the curves exhibit temperature inversions and marked changes in the dew point lapse rate due to air

mass modification by passage over cool water, to subsidence, or to the presence

of cold or warm fronts. No summary of the climatological picture is attempted, but

this can be had by careful examination, and comparison, of the individual profiles.

(Met. Abs. 8I-22)-R.S.Quiroz
10

E-41 Crawford, A. B. and Sharpless, W. M. , Further observations of the angle of arrival

of microwaves. Institute of Radio Engineers, N. Y. , Proceedings, 34(11): 845-848,

Nov. 1946. 3 figs. , 5 refs. DLC --Observations in the summer of 1945 with a specially built antenna with about 2^ sharper beam operating at 1. 25 cm are discussed here. Small abrupt changes in the refractive index such as may be present

at the boundaries of inversion layers may be responsible for high angle components,

rather than superrefraction in inversion layers. The multiple path transmission may

be closer to its clarification if simultaneous measurements were made of angle-ofarrival in line paths of different lengths. (Met. Abs. 8I-23)--W. N.

E-42 Fok, Vladimir Aleksandrovich, Diffraktsiia radiovoln vokrug zemnoi poverkhnosti.

(Diffraction of radio waves around the Earth's surface. ) Moscow, Akademiia

NaukSSSR, 1946. 79 p. 6 figs. , tables p. 62-79, 4 refs. , numerous eqs. DLC--

This is a theoretical study of radio wave propagation around a homogeneous surface

of the earth, accounting for diffraction but not for ionospheric effects. The purpose

is to develop formulas for wave amplitudes as a function of height of the source,

its distance, wavelength and electrical properties of the ground. The most important result of the work is the development of a formula for the attenuation coefficient in the form of an integral. A detailed analysis shows that this formula is

applicable to all situations encountered in practice. The results obtained are in

agreement with other theories. Entirely new results were obtained in the half

shadow zone (near the horizon). Formulas have been worked out, giving an uninterrupted transition from the light to the shadow zone. In all cases the numerical

method of calculating the superimposed series and integrals are indicated.

--Transl. of author's abstract.

E-43 McPetrie, J.S.and Ford, L.H. , An experimental investigation on the propagation

of radio waves over bare ridges in the wavelength range 10 cm to 10 m. Institution

of Electrical Engineers, London, Journal, Pt.IIIA, 93(3): 527-530, 1946. 10 figs. , table, 6 refs. DLC--The variation in received field strength has been investigated as a receiver was moved over the crest and into the shadow of a bare ridge which

approximated in contour to a cylinder. The rate of attenuation in the shadow of

the ridge was found to agree, using horizontally polarized radiation, with values

calculated from the formulae of Domb and Pryce over the whole range of wave

lengths used, 9.2 cm to 11. 15 m. --Authors' abstract.

E-44 McPetrie, J.S.and Ford, L.H. , Some experiments on the propagation of radiation

of 9. 2 cm wavelength, especially on the effect of obstacles. Institution of Electrical Engineers, London, Journal, Pt.IIIA, 93(3): 531 -538, 1946. 9 figs. , 6

tables. DLC --The salient results are brought together of a number of experiments on the propagation of radiation of a wavelength of 9. 2 cm, carried out during 1943-

44. All the measurements described were made over land, some over open country

and some over transmission paths which were obstructed by various obstacles.

The obstacles included trees, both leafless and in full leaf, brick walls, windows,

and other parts of buildings. Many of the obstacles caused such large attenuation

that they should generally be regarded as opaque objects round which diffraction

takes place. Stone buildings, groups of trees so dense that the sky cannot be seen through them, and the trunks of trees come into this category. Semi transparent obstacles (causing a loss of signal of 10 db or less), include windows,

tile or slate roofs, the sides of a light wooden hut, and thin screens of trees when

the transmission path lies through the branches. —Authors' abstract.
11

Megaw, E.C.S., Experimental studies of the propagation of very short waves . Institution of Electrical Engineers, London, Journal, Pt.IIIA, 93(l):79-97, 1946.

23 figs. , 3 tables, 4 eqs. DLC--The paper presents a survey of the experimental

work on the propagation of very short waves, and especially of centimeter waves,

carried out in England during World War II. Preliminary experimental studies over

land and sea paths are described, with a summary of the tentative conclusion to which they led. The main experimental programme consisted of measurements of

3 cm, 9 cm, and 3& m waves over sea path 57 mi and 200 mi in length; and of

9 cm waves over a single 38 mi land path. In a concluding Section, some investigations into special aspects of very short wave propagation are described; data on reflection from sea and land, and on the effect of obstacles are also included.

--From author's abstract.

Radio Corporation of America. David Samoff Research Center, Princeton, N.J. , Television: a bibliography of technical papers by RCA authors, 1929-1946.

RCA Review, 1946. 10 p. DLC (Z7711. R3) -Several of the 275 technical papers,

listed in chronological order 1929-1946, have a bearing on aspects of tropospheric

propagation. --W. N.

1947

Bullington, Kenneth, Radio propagation at frequencies above 30 megacycles.

Institute of Radio Engineers, N. Y. , Proceedings, 35(10): 1122-1136, Oct. 1947.

14 figs. , 2 tables, 10 refs. , 20 eqs. DLC --The results of this detailed study on

factors influencing radio propagation (frequency, distance antenna heights, earth's

curvature, atmospheric conditions, ground obstacles) are presented in a series of

nomograms that quickly give an estimate of the received power and received field

intensity for a given point-to-point transmission path. Comparison between empirical methods to estimate a. o. , the effect of atmospheric refraction and other factors,

with experimental data on shadow losses and fading ranges, is presented. (Met.

Abs. 8 1-25) -From author's abstract.

Domb, C.and Pryce, M.H.L., The calculation of field strengths over a spherical

earth. Institution of Electrical Engineers, London, Journal, Pt. Ill, 94(30):325=

339, July 1947. 16 figs. , 44 eqs. DLC --Curves and formulas are given for the

calculation of field strength at any height and distance from the transmitter for the case of horizontally polarized electromagnetic waves over a curved Earth or sea. Sufficiently within the optical range the field is calculated by ray theory,

and appropriate quantities for calculating path difference and divergence of re- flected ray are given. The case of vertically polarized waves is also briefly discussed, and curves and formulas are given for the reflection coefficient (including

surface-wave term) where ray theory is applicable, and for one term of the diffraction formula in the region well beyond optical cutoff. --From authors' abstract.

Miller, G.A. ; Halbert, H. W. ; Doherty, L.H. and Swanson, D. A. , Final report

Suffield Tropospheric Project . Canadian Radio Wave Propagation Committee, Feb.

20, 1947. 39 sheets, numerous figs. , numerous graphs, 10 refs. --This is the

third of three reports and gives the (final) results of the tropospheric propagation

experiments carried out at Suffield, Alberta from June 1, 1945 through April 1,

1946. Some results obtained from radar observations or echoes (spaced comer

reflectors) are given. (Met. Abs. 8 1-29)-- W.N.
12

E-50 Norton, K.A.and Omberg, A., The maximum range of a radar set . Institute of

Radio Engineers, N. Y. , Proceedings, 35(l):4-24, Jan. 1947. 11 figs. , 2 tables,

36 refs. , 70 eqs. DLC --Formulas to calculate the maximum range of a radar set

are demonstrated here along with several of the factors analyzed on which a given

radar set depends for maximum range. In addition to electronics, etc. , the meteorological elements involved in radio wave propagation are discussed. (Met. Abs.

8I-30J--W.N.

E-51 Physical Society of London and Royal Meteorological Society, Meteorological

factors in radio wave propagation; report of a Conference held on April 8, 1946

at the Royal Institution. London. London 1947? 325 p. Figs. , tables, refs.

GB-MO. Review by H. Koschmieder in Zeitschrift fur Flugwissenschaften, Brunswick, 2(6): 156, June 1954. DLC --This report includes 21 papers describing var- ious investigations concerned with the effect of the meteorological conditions of

the lower atmosphere on the bending of very short radio waves transmitted through

it. The list of contributions is as follows: APPLETON, SIR EDWARD, The influ - ence of tropospheric conditions on ultra short wave propagation, p. 1-17. SMITHROSE, R.L. and STICKLAND, A.C., An experimental study of the effect of

meteorological conditions upon the propagation of centimetric radio waves, p. 18-

37. SHEPPARD, P. A., The structure and refractive index of the lower atmosphere , p. 37-79. BOOKER, H. G. and WALKINSHAW, W. , The mode theory of tropospheric

refraction and its relation to wave guides and diffraction , p. 80-127. HARTREE,

D.R., MICHEL, J.G.L. and NICOLSON, PHYLLIS, Practical methods for the

solution of the eguations of tropospheric refraction, p. 127-168. RYDE, J. W. , The attenuation and radar echoes produced at centimeter wavelengths by various

meteorological phenomena, p. 169-139. WESTWATER, F.L. , Radar storm detectionl . p. 190. ROSS, R.G. , Radar storm detection II . p. 190-193. DURST, C.S. , Radio

climatology , p. 193-212. JOHNSON, SIR NELSON K. , Meteorological investigations

in connection with radio propagation, p. 212-215. SAXTON, J. A., The dielectric

properties of water vapor at very high radio frequencies, p. 215-238. RAMSAY,

J. A., The vertical distribution of radar field strength over the sea under various

conditions of atmospheric refraction , p. 238-242. ALEXANDER, F.E.S., Observa - tions of unorthodox radar vision in the vicinity of New Zealand and Norfolk Island . p. 242-249. MACFARLANE, G. G. , A method for deducing the refractive index

profile of a stratified atmosphere from radio observations, p. 250-252. STICKLAND,

A.C., Refraction in the lower atmosphere and its application to the propagation of

radio waves , p. 253-267. BEST, A.C., A standard radio atmosphere for microwave

propagation, p. 267-273. BULL, G.A. , Note on errors in measurement of the refrac - tive index of the air for high frequency radio waves conseguent upon errors in

meteorological measurements, p. 273-278. SAXTON, J. A. and LANE, J. A., The

anomalous dispersion of water at very high radio freguencies . Pts. I-IV, p. 278-

325. (Met. Abs. 81-31)

E-52 Pickard, Greenleaf W. and Stetson, Harlan T. , Tropospheric reception at 42. 8 mc

and meteorological conditions . Institute of Radio Engineers, N. Y. , Proceedings,

35(12): 1445-1450, Dec. 1947. 16 figs. DLC--Data of the alpine FM Station

W2XMN transmissions over the 167 mi path to Needham, Mass. , are analyzed

and presented in diagrams. This purely tropospheric propagation as influenced

by meteorological elements showed a distinct seasonal change, higher in summer

because of surface refraction favored by maximum water vapor pressure. All

frontal passage lowered transmission but in relation to angle of passage with the

transmission path. Better transmission in calm weather may be due to favorable

stratification otherwise reduced by turbulence. (Met. Abst. 8l-32)--W. N.
13

Smyth, J. B. and Trolese, L.G. , Propagation of radio waves in the troposphere . Institute of Radio Engineers, N. Y. , Proceedings, 35(1): 1198-1202, Nov. 1947.

6 figs. , 21 refs. , 3 eqs. DLC--A theory based on three experimental types of

index of refraction distribution is discussed here. The refracting stratum treated as a plane refracting layer, generally agrees with propagation experiments as con- ducted over a 90 mi nonoptical over water path at San Diego, records of which are shown and presented graphically for comparison with calculated results. (Met.

Abs. 81-33) --W.N.

Waynick, A. H. , Ultra short wave propagation studies beyond the horizon . Institute of Radio Engineers, N. Y. , Proceedings, 35(11):1334, Nov. 1947. 5 figs. , 3 refs. --A brief presentation of data which are believed to: a) verify the statements

of G.S. Wickizer and A.M.Braaten to the effect that atmospheric heights greater

than about 100 ft are effective in returning signals back toward the Earth; and b)

indicate that the portion of the atmosphere so effective is the region below about

1. 5 km for the experimental conditions involved. --E. K.

Wickizer, G.S. and Braaten, A.M., Propagation studies on 45. 1. 474 and 2800

megacycles within and beyond the horizon. Institute of Radio Engineers, N. Y. , Proceedings, 35(7): 670-680, July 1947. 20 figs. , 3 tables, 8 refs. , 3 eqs. DLC--

Continuous recordings of field strength on 474 and 2800 megacycles, over a per- iod of 13 months, revealed maximum values three to four times the free space

field at distances of 42. 5 and 70. 1 mi from the transmitting site atop Empire State

Building, N. Y.C. Recordings on 45. 1 megacycles during the same period, on a reduced schedule, did not exhibit the large variation found on the higher frequencies. Refraction was found to be greater in summer time, the strongest periods

occurring during night or early in the morning. Refraction greater than normal

was not evident when the average wind velocity was above 13 mi per hr. A study

of weather conditions during the periods of strongest refraction indicated that

roughly 60% of the gradients were of the frontal type, involving different air masses, and approximately 60% of the gradients were higher than 100 ft above the

earth's surface. (Met. Abs. 8 1 -34) --Authors' abstract.

1948

Booker, H. G. , Some problems in radio meteorology. Royal Meteorological

Society, Quarterly Journal, 74(321-322) :277-315, July-Oct. 1948. 19 figs. , 2

tables, 21 refs. , 35 eqs. DWB, DAWS--Superrefraction of radio wavelengths

less than about 10 m in the lower troposphere may occur with an inversion of

temperature exceeding 5 F°/100 ft, or a lapse of humidity greater than 0. 52

gm/kg/100 ft, or by a combination of these. The principal meteorological phenomena likely to cause radio refraction are nocturnal radiation inversions over

land, advection of warm dry air over a cold surface, and low level subsidence

inversions. Coastal and sea areas of the world found during World War II to be

subject to superrefraction are listed. The conjugate power law theory of eddy

diffusion is applied to ascertain the profiles of temperature and humidity associated with inversion phenomena, and a comparison is made with observed temperature and humidity profiles (M.I. T. data). The comparison suggests that

lack of complete correspondence is attributable to the assumption that the coefficient of eddy diffusion is constant with height. (Met. Abs. 8I-35)--R.S.Quiroz.
14

E-57 Durkee, A.L., Results of microwave propagation tests on a 40 mi overland path.

Institute of Radio Engineers, N. Y. , Proceedings, 36(2): 197-205, Feb. 1948. 15

figs. DLC--The 2 yr (July 1943-Feb. 1945) tests with 1. 25 to 42 cm wavelengths

over a 40 mi path from New York to Neshanic showed waves well above 3 cm to be

preferred rather than lesser wavelengths. The influence of meteorological, as well as diurnal and seasonal, factors on propagation is shown graphically and discussed.

(Met. Abs. 8I-36)--W. N.

E-58 Gerson, N. G. , Variations in the index of refraction of the atmosphere. Geofisica

Pura e Applicata, 13(3/4):88-101, Sept. /Oct. 1948. 12 figs. , 2 tables, 22 refs.,

26 eqs. DLC (QC801. G37)- -Several aspects of the refractive index variations are considered such as: (1) throughout the year at the earth's surface and (2) seasonally in several air masses, where monthly and seasonal values are employed.

Graphical presentation of the variation of the refractive index with altitude is

given for the more general air masses. Up to 6 km altitude, tropical and monsoon

air masses had highest values, arctic air masses the lowest. Rate of decrease

with altitude (up to 6 km) varies in accord with air masses, rate of decrease was

more constant in upper air masses than in lower. (Met. Abs. 81-38)-- vV. N.

E-59 Hamlin, E. W. and Gordon, W. E. , Comparison of calculated and measured phase

difference at 3.2 cm wavelength. Institute of Radio Engineers, N. Y. , Proceedings, 36(10): 1218-1223, Oct. 1948. 9 figs. , 3 refs. , 7 eqs. DLC -Radio propagation and associated meteorological measurements, made by the Electrical Engineering Research Laboratory of the University of Texas during April 1946, on a path from Gila Bend to Sentinel in the Arizona desert, show that, for meteorological conditions that could be represented by a linear M curve, the magnitude and

phase of the field resulting from propagation over a 27 mi path on 3 cm could be

calculated on the basis of a direct wave, and one reflected from a surface tan- gent to the actual profile at the point of reflection. Apparent reflection coefficients between 0. 3 and 0. 8 were found for desert sand on 3 cm for this path.

(Met. Abs. 8 1-39) -Authors' abstract.

E-30 Kerr, Donald E. , Propagation of very short waves, Pt. 1 . Electronics, 21(1): 124-

128, Jan. 1948. 6 figs. , 2 refs. , 26 eqs. Pt. 2 . Ibid., 21(2):118-123, Feb. 1948.

5 figp. , ref. , 8 eqs. DLC--An excellent outline with new light on the subject,

comprising the M.I.T. Radiation Laboratory experiments in summarized form. Also

with those of many other investigators from various parts of the world. In the

first part, author discusses the one way propagation in free space and over a spherical earth. Second part is devoted to surface reflection effects, radar type

propagation, and finally, propagation caused by atmospheric refraction which is

given particular consideration. The atmospheric index 7? depends on pressure

temperature and humidity but is independent of wavelength down to about 1 cm

(where absorption becomes important). The index gradient dfc/dz involves both

the gradients of the atmospheric quantities and their values, resulting in the

possibility of wide range of effects on the modified index profile of which the

most important are: (1) In a completely vertically mixed atmosphere oily/dz

is nearly constant (0. 036 per ft defined as giving standard refraction). (2) Temperature inversions tend to make dN/dz «= 0. 036 and (3) Decrease of water vapor

pressure or concentration with height trends to make dN/dz *= 0. 036. (4) Increase

of humidity (the relative, not a conservative property of atmosphere, is considered

a useless quantity here) with height, tends to make dN/dz =• 0.036. (Met. Abs.

8 1-40) -W.N.
15

-61 Kerr, F. J. , Radio superrefraction in the coastal regions of Australia. Australian

Journal of Scientific Research, Ser. A, Physical Sciences, l(4):443-463, Dec.

1948. 14 figs. , 9 refs. --A study of the geographical and meteorological factors

affecting superrefraction of radio or radar echoes in and near Australia. Based on

reports from 112 RAAF radar warning stations (March 1944 to Aug. 1945), the

study shows that: 1) seasonal and diurnal variations are marked, but opposite

on the North and South coasts (maximum in summer in the South); 2) the most in- tense superrefraction occurs in the West Coast region and 3) the most favorable

synoptic conditions is hot, dry air from interior above cool, moist sea air moving

ashore. (Met. Abs. 2. 3-173)--M. R.

-62 Klinger, Hans Herbert, Erzeuqung. Ausbreitung und Anwendung von Millimeter- wellen. (Generation, propagation and application of millimeter waves.) Das

Elektron, Munich, 2(10): 213-214, Oct. 1948. DLC -Propagation of millimeter waves is characterized by scattering-absorption (scattering and refraction by water

drops, absorption by water vapor and oxygen) increasing proportional with distance

of transmission and reciprocal proportional to the fourth power of the wave length.

The absorption is explained by certain quantum conditions of the molecules of

oxygen and water vapor which frequencies do appear in these very short waves. (Oxygen has an absorption region at 2. 5 mm and 5 mm waves, water vapor at 1.34 cm and some mm waves). Propagation experiments with 6 mm waves (beyond

molecular absorption) show that in a nonturbulent atmosphere, transmission can be made over 30 km distance. (Met. Abs. 8 1-42) -W. N.

-63 Megaw, E.C.S., Some effects of obstacles on the propagation of very short

radio waves. Institution of Electrical Engineers, London, Journal, Pt. Ill, 95(34) -.97-105, March 1948. 16 figs. , table, 3 refs. , 15 eqs. DLC-Experimentally observed effects of localized obstacles, reflection, and shadowing

on dm and cm radio waves are discussed, and compared favorably with theoretical results. --W. N.

-64 Norton, Kenneth A. , Propagation in the FM broadcast band. Advances in

Electronics, 1:381-423, 1948. 16 figs. , table, 28 refs. , 8 eqs. DLC -In his

introduction author explains FM propagation generally and subsequently dis- cusses the following topics: Interference due to long distance ionospheric

propagation. Effects of radio noise on broadcast reception. Effects of antenna

height and terrain on the effective transmission range over a smooth spherical

earth. Effects of irregularities in the terrain. Systematic effects of terrain and

tropospheric ducts. Tropospheric waves resulting from reflection at atmospheric

boundary layers. Combined effects of ducts and random tropospheric waves.

Calculated service and interference ranges of FM broadcast stations. The

efficient allocation of facilities to FM broadcast stations. Optimum frequency

for an FM broadcast service. (Met. Abs. 8I-43)--W. N.

-65 Perlat, Andree, Meteoroloqie et radioelectricite. (Meteorology and radioelectricity. ) L'Onde Electrique, 28:44-54, 1948. 18 figs. DLC -The first part of

this article deals with the uses of radio and radar in meteorology. Pt. 2 describes with diagrams, the effect of meteorological phenomena on the propagation and refraction of waves of frequency exceeding 60 Mc/s. Factors con- sidered are variation of refractive index with height, effect of turbulence, advection, nocturnal cooling, fog, subsidence, fronts and the formation of ducts.

(Met. Abs. 8I-45)--C.E.P.B.
16

E-66 Price, W.L., Radio shadow effects produced in the atmosphere by inversions.

Physical Society of London, Proceedings, 61(343): 59-78, July 1, 1948. 9 figs. , 10 refs. , 32 eqs. DLC--For frequencies around 200 Mc/s it appears likely that

certain predictable weather situations are associated with shadow zones (airplanes will not be detected). Author concludes with advice to those using high

frequency sets in localities subject to strong inversion. At times, failure in

system may occur due to meteorological conditions. (Met. Abs. 8I-46)--W. N.

E-67 Rydbeck, OlofE.H. , On the propagation of waves in an inhomoqeneous medium.

Goteborg, Sweden. Chalmers Tekniska Hogskola, Handlingar, No. 74; Reports

from the Research Laboratory of Electronics, No. 7, 1948. 34 p. 7 figs. , 18 refs.,

137 eqs. DLC--The paper opens with a discussion of, and the connection between,

the existing theoretical methods of propagation, both in slightly and strongly

homogeneous media. Author proved that the reflection intensity as calculated by

the good path method is correct. A complete, mathematical expression for the

wave phase is presented. Finally, the circuit relation of the wave equation is

demonstrated in the light of (1) ALFVEN's magneto hydrodynamic waves in the sun and (2) duct propagation of microwaves in the lower troposphere. (Met. Abs.

8I-47)-W. N.

E-68 Smith-Rose, R.L., Meteorology and the propagation of radio waves. Nature,

London, 161(4082) -.145-146, Jan. 24, 1948. --Review of work done during the war, especially reports prepared for general distribution after the war, on determination of the effect of various weather conditions on radio and radar propagation.

(Met. Abs. 1-176).

E-69 Straiton, A. W. and Gerhardt, J. R. , Results of horizontal microwave anqle-ofarrival measurements by the phase difference method. Institute of Radio Engineers,

N. Y. , Proceedings, 36(7):916-922, July 1948. 12 figs. , 2 tables, eqs. DLC--

Radio and meteorological equipment employed are described and results

obtained are discussed. The observations were conducted at Corpus Christi, Texas.

Sixty percent of the measurements showed angular deviation less than 0. 03° and

was found to be directly proportional to path length if constant gradient persists over the path. The angle of arrival as a function of gradient of index of refraction

is considered. (Met. Abs. 8 1-49)-- W.N.

E-70 Thompson, Leland E. , Microwave propagation experiments. Institute of Radio

Engineers, N. Y. , Proceedings, 36(5):671-676, May 1948. 5 figs. , 13 refs.

DLC --Propagation tests at frequencies between 3000 and 4000 Mc are described.

The effect on the received signal of changes in the index of refraction of the atmosphere are discussed, and means are suggested for minimizing signal variations

with particular regard to the application of microwave relay communication systems. Theoretical data is given on diffraction at these frequencies. —Author's

abstract.

1949

E-71 Bremmer, H. , Terrestrial radio waves: theory of propagation. New York, Elsevier

Publ.Co. , 1949. 343 p. 91 figs. , numerous refs. , eqs. DLC--The theoretical

aspects of propagation are discussed. The classic papers of VAN DER POL and

BREMMER (1930) on propagation over a curved earth are included. (Met. Abs.

81-54)- -W. N.
17

E-72 Dattan, W. , Beitrag zur unnormalen Brechunq ultrakurzer Wellen in der Atmosphare. (Contribution to abnormal refraction of ultra short waves in the atmosphere.) Zeitschrift fur Meteorologie, 3(l/2):50-51, Jan. /Feb. 1949. Fig., ref. DWB--The 7. 9 m wave was received at a distance of 180 km, due to reflection

from a relatively low layer in the atmosphere. (Met. Abs. 81-56)—C. E. P. B.

E-73 Davies, H. , A preliminary study of some results from the radio-meteorological

investigation conducted in Canterbury. Royal Society of New Zealand, Transactions, 77(5):78-85, Nov. 1949. 10 figs. DLC--The mechanics of orthodox propagation of cm waves in a well mixed atmosphere are discussed, including lobe

distribution above the horizon due to interference of direct and reflected rays.

Anomalous propagation in a duct is considered and the effect of a land-sea transition on the vertical structure of potential temperature, specific humidity, modified

refractive index and duct shape in a typical NW advective duct are illustrated.

These cause considerable superre fraction of wavelengths of 3 and 10 cm.

(Met. Abs. 8I-57)-C.E.P.B.

E-74 Griin, Artur and Kleinsteuber, Werner, Der durch den Feuchtigkeits- und Temperaturqang der unteren atmospharischen Schichten verursachte Interferenzschwund im Dezimeterqebiet . (The interfering fading in the decimeter band, caused

by the temperature and humidity variation of the lower layers of the atmosphere.

)

Archiv der Elektrischen Ubertragung, 3(6):209-219, Sept. 1949. 18 figs. , 10

refs. , 20 eqs. DLC--Since the changeable curvature of a ray is due to the

weather dependent gradient of the index of refraction, the difference in variation

of both rays (i. e. , the direct and the earth reflected) gives simple formulas for calculation of the field strength. Observational results evaluated by this method

were found in good agreement with available meteorological observations.

(Met. Abs. 8 1-60) -W.N.

E-75 Harris, Donald B. , A forward transmission echo ranging system. Institute of

Radio Engineers, N. Y. , Proceedings, 37(7): 767-770, July 1949. 4 figs. , 15 eqs.

DLC--A new system using radar techniques is described. Receiver and transmitter

are placed at separated locations. Range of target to receiving station being

equal to difference in paths between direct and reflected waves divided by the

versine of the angle of elevation of the receiving antenna, the radial waiting

speed is made proportional permitting a PPI presentation of propagation path as seen from the side. Application of the system to propagation studies is promising. (Met. Abs. 8 1-61) -W.N.

E-76 Herath, Fritz, Inversionsstudie auf Grund der Lindenberger Fesselaufstiege mit

besonderer Berucksichtigung der Ultrakurzwellenausbreitung. (Inversion study

based on the captive balloon ascent at Lindenberg Observatory, with special

attention to the propagation of ultra short waves. ) Germany. Deutscher Wetterdienst in der U.S. Zone, Berichte, No. 9, 1949. 41 p. 20 figs. , 29 tables,

57 refs. DWB--In an extensive study of inversions 2 3. 0°C, which appeared

between the ground surface and 2000 m, 17, 586 captive balloon ascents and

kite flights at Lindenberg Observatory (1903-1925) were analyzed. Annual variation, frequency and various characteristics of inversions are presented. The

strongest inversion occurred in December when temperature on the ground was

- 15.2° C, and at the altitude of 850 m + 1.9° C. The strong inversions 2

10. 0° C make 3. 7% of all the cases. Temperature gradient in the free inversions

is calculated in order to calculate the propagation of the ultra short waves. The observed maximal value was 71°/100 m. The maximal value of ideal inversions calculated after A. WEGENER was found to be approximately 43°. (Met.

Abs. 8I-62)-W. N.
18

// E-77 Israel, Hans and Sommermeyer, K. , Uber partielle Reflexion elektromaqnetischer

Wellen in der Troposphare . (Partial reflection of electromagnetic waves in the

troposphere.) Zeitschrift fur Meteorologie, 3(l-2):32-39, Jan. -Feb. 1949. 2 figs.,

12 refs. , eqs. DLC--A marked partial reflection of electromagnetic waves by

atmospheric formations can only occur if the dielectric constant at the reflecting

surface changes considerably in a distance shorter than or at the most, of the

same order as the wavelength. Most reflections at inversions, etc. , are limited

to waves of a few hundred meters or more. Decimeter waves can be reflected by

water vapor discontinuities in transient turbulent eddies, mostly over the sea,

and in thunderclouds and the space above them. Uniform ionization density in a thundercloud cannot explain reflection, and authors suggest local ionization in

discharge channels. (Met. Abs. 11-175)--C. E. P. B.

E-78 Jones, R.F. , Low level atmospheric ducts . Nature, London, 163(4147) -.639,

April 23, 1949. 2 refs. Discussion by J. S. McPetrie and B. Stamecki, p. 639.

DLC --Jones presents a plausible hypothesis for the formation of low level radio

transmission ducts over the sea during strong wind conditions and during still

air. Humidity lapse rates when strong winds come from cold areas, and temperature and humidity lapse rates when winds come from warm areas, create conditions favorable for these "ducts" in the lower 100 ft above the sea. Presence

of spray also considered important during turbulent conditions (discussion).

(Met. Abs. 8I-65)--M.R.

E-79 Jones, F. E. and Cornford, E.C., The measurement of the velocity of propagation

of centimeter radio waves as a function of height above the earth. Pt. 2. Institution of Electrical Engineers, Proceedings, Pt. 3, 96(43) :447-452, Sept. 1949.

8 figs. , 7 tables, 5 refs. , 6 eqs. DLC--Includes nomogram for computing variation of refraction index of atmosphere with height above earth. Velocities given

for propagation between ground and 10, 20 and 30 thousand feet respectively

(186,233; 186,246; and 186, 256 mi/sec). (Met. Abs. 2. 3-41)—-M. R.

E-80 Kirke, H.L., Calculations of ground wave field strength over a composite land

path. Institute of Radio Engineers, N. Y. , Proceedings, 37(5):489-496, May

1949. 13 figs. , foot -refs. DLC--A brief discussion of the problem is given,

together with a description of the three proposed methods of solution. The re- sults of a practical experiment are shown and curves calculated by the three

methods are compared with the observed results. It is shown that the BBC

method gives field strengths much nearer to the observed values than the P. P. Eckersley method, and that the method proposed by G. Millington, while somewhat more laborious to use, also gives results which agree well with observed

values. The difference between the three methods is small at low frequencies

and when the effect of the discontinuity is not large. --Author's abstract.

E-81 Krasil'nikov, V.A. , O vliianii pulsatsii koeffitsienta prelomleniia v atmosfere na rasprostranenie ul'trakorotkikh radiovoln. (Influence of pulsations of the

index of refraction in the atmosphere on the propagation of ultrashort radio waves.)

Akademiia Nauk SSSR, Izvestiia, Ser. Geogr. i Geofiz. , 13(l):33-57, 1949.

7 figs. , table, 16 refs. , 60+ eqs. DWB, DLC --Fluctuations in the index of re- fraction of the atmosphere, due to temperature pulsations, causing fluctuations

in signal strength, phase, etc. , (fading^ of high frequency radio waves, both

up to and beyond the horizon. Comparison of theory with experimental results.

(Met. Abs. 81-66)
19

E-82 Lehfeldt, Wilhelm, Die Ausbreitunq der Ultrakurzen (quasioptischen) Wellen.

(Propagation of ultrashort (quasi-optical) waves.) Archiv der Elektrischen IJbertragung, 3(4-9): 137-142, 183-186, 221-228, 265-269, 305-312, 339-346, JulyDec. 1949. 44 figs. , 8 tables, 49 refs, num. eqs. DLC -This detailed study

contains two main parts. The first part discusses such problems as: (1) refraction of the ray in a homogeneous atmosphere, (2) refraction and reflection in an inhomogeneous atmosphere, (3) reflections and blurred boundaries, (4) influence

of ions upon reflection and refraction, (5) suppression by scattering and absorption. Influence of the earth's surface. In the second part, devoted to discussion of the results obtained by measurement, the following topics are highlighted:

(1) The technique of measurements, (2) Measurements of over-land propagation,

(3) Statistical over-land results, (4) Measurements over the sea, and at 9 cm

wavelength over plain lowland, (5) Ranges. (Met. Abs. 8I-67)--W. N.

E-83 Mcpetrie, J. S. ; Starnecki, B. ; Jarkowski, H. and Siscinski, L. , Oversea propagation on wavelengths of 3 and 9 centimeters. Institute of Radio Engineers, N. Y.,

Proceedings, 37(3):243-257, March 1949. 16 figs. , 2 tables, 10 refs. , 5 eqs.

DLC --Tests 1943-1946 to determine meteorological factors governing propagation

of cm waves are discussed here. The results summarized cover continuous re- cordings of field strength at the over-sea paths 60 and 200 mi off the west coast

of Great Britain. Radio results and meteorological parameters are considered in

relation to current propagation theories. (Met. Abs. 8I-68)--W. N.

E-84 Millington, G. , The reflection coefficient of a linearly graded layer . Marconi

Review, London, 13(96): 140-151, 1949. 23 figs. --The curves given in this paper

refer to the specific problem of the reflection of a horizontally polarized plane

wave incident obliquely on a layer in which there is a linear variation of dielectric constant, and hence, of the square of the refractive index, from some constant value on one side of the layer to some other constant value on the other

side of the layer. They have a particular application to the propagation of ultra

high frequency radio waves in the troposphere, and should, therefore, be a useful contribution to our knowledge of long distance transmission on these frequencies. The curves refer only to the case of horizontal polarization. The curves

for horizontal polarization give also the numerical value of the reflection coefficient for vertical polarization to the accuracy to which they can be used.

--From author's abstract.

E-85 Perlat, A. , Effet des conditions meteoroloqigues sur la propagation des ondes

radioelectriques a freguence eleve^e. Note preliminaire. (Effect of meteorological

conditions on the propagation of high frequency waves: preliminary note.) Journal

Scientifique de la Meteorologie, Paris, 1(4):131-138, 1949. 8 figs. , tables.

Cas des ondes de 150 Mc. (Case of waves of 150 Mc.) Ibid. , 2(8):101-107,

Oct. -Dec. 1950. 3 figs. French, English and Spanish summaries p. 131, 101.

DWB--The first memorandum discusses the meteorological conditions for the

existence of ducts giving abnormally large reception range of waves shorter than

10 m, making use of radiosonde ascents. In the second paper, several cases of

very abnormal range (300-400 km) of 2 m waves in Western Europe are examined.

They appear to require the presence of a subsidence area, pressure above 1013

mb and vapor pressure above 11 mb, and no fronts across the track. (Met. Abs.

81-69).
20

E-86 Rocco, M.D. and Smyth, J. B. , Diffraction of high frequency radio waves

around the earth . Institute of Radio Engineers, N. Y. , Proceedings, 37(10):

1195-1203, Oct. 1949. 14 figs. , 17 refs. DLC--This paper reports nonoptical height gain measurements on a remarkably uniform desert link at fre- quencies of 25, 63, 170, 520, 1000, 3000, and 9375 Mc using horizontal

polarization. It has been shown that when the index of refraction of the at- mosphere is a linear function of elevation, the problem of refraction and diffraction may be presented approximately by a problem in diffraction alone.

Data taken under linear and slightly nonlinear index of refraction gradients

are compared with fields predicted by standard diffraction theory. A mechanism other than diffraction is required to explain the higher frequency

fields observed under standard meteorological conditions. (Met. Abs.

8 1-70) -Authors' abstract.

E-87 U.S. Office of Scientific Research and Development. National Defense

Research Committee, Radio wave propagation: consolidated summary

technical report of the Committee on Propagation. Charles R. Burrows,

Chairman. Stephen S. Attwood, editor. N. Y. , Academic Press, 1949.

3 vol. in 1. 548 p. Figs., tables, bibliogs. , eqs. "Reprinting, with

some omissions of the 3 volumes pub. 1945? in a limited edition. " Bibliog. p. 514-530. General bibliog. of reports on tropospheric propagation, Report WPG-14 (Columbia Univ. Wave Propagation Group) p. 530-548.

Numerous figs. , tables, bibliogs. and eqs. DLC (QC66 1. U63)- -This comprehensive work on radio wave propagation through the troposphere comprises scientific information and reports of experiments. Vol. 1, entitled

Technical survey, is largely a critical and general review of the technical

developments of the tropospheric propagation problems. The general

theory of standard and of nonstandard propagation with descriptions and

results of transmissions, as well as the meteorological factors affecting

propagation and attenuation, are treated. Vol. II, entitled Radio wave

propagation, is devoted to meteorology. Such subjects as theory, equipment, development of forecasting techniques are dealt with in the first

part; second part contains significant information and data on subjects

such as reflection coefficients, dielectric constant, absorption, scattering

(rain, drop size) echoes, targets, etc. Radar, in its relation to these factors, is given a detailed treatment. A consideration of angle-of-arrival is

included. Vol. Ill, entitled The propagation of radiowaves through the

standard atmosphere, is of particular interest to the (meteorological)radar

operators. Propagation of waves above 30 Mc is discussed specifically

here. Six transmission experiments at such different geographical locations as Massachusetts Bay, San Diego, Arizona, Antigua, West Indies

and Great Britain are considered in detail in order to correlate practice with

the theories discussed in Vol. I and the meteorological factors discussed

in Vol. II. The comprehensive bibliographies consist of 450 entires for

Vol. I and 123 + for Vol. II, and the general bibliography of reports (557

entries) includes the works from numerous service and civilian organizations in the U.S. , Great Britain, Canada, New Zealand and Australia.

(Met. Abs. 8 1-71) -W.N.
21

Unwin, R.S., Some problems and techniques involved in the radiometeoroloqical

investigation conducted in Canterbury. Royal Society of New Zealand, Transactions, 77(5):85-91, Nov. 1949. 7figs. , 4 refs. DLC --Study of radar ducts made

during late 1946 and 1947 during l&hn (off shore) wind on coast of New Zealand —

range 200 km from coast and 600 m above sea level. Isopleths of atmospheric

factors and refraction index. (Met. Abs. 8I-72)--M.R.

1950

Aslakson, Carl I. and Fickeissen, Omar O. , The effect of meteorological conditions on the measurement of long distances by electronics. American Geophysical

Union, Transactions, 31(6):816-826, Dec. 1950. 6 figs. , 3 tables, 6 refs. , 10

eqs. DWB--Practical methods for correcting long distance electronic measurements,

limited to frequencies peculiar to shoran or from about 220 to 250 megacycles per

second for variations in meteorological conditions, are described. The following

topics are considered: the technique of making meteorological observations by

airplane; the empirical relationship expressing the index of refraction in terms of

total pressure and water vapor pressure in millibars and absolute temperature (relationship used for U.S. Air Force projects); the manner in which curvature of the

shoran ray affects geodetic distance; the methods of correcting for ray path cur- vature used by the U.S. Air Force, by Canada and by KROLL (U.S. Army Map

Service); the effect of meteorological variations upon the velocity correction; the

analysis of errors due to the uncertainty of the velocity of radio waves in a vac- uum and to the uncertainty of the index of refraction of moist air. (Met. Abs.

8I-74)-I.L.D.

Birnbaum, George, A recording microwave refractometer. Review of Scientific

Instruments, N. Y. , 21(2) -.169-176, Feb. 1950. 7 figs. , 9 eqs. , 23 refs. DLCAn instrument designed to measure and record a small difference in frequency between two cavity resonators is described. A sweep frequency technique is used

to generate the resonance responses of the cavities. These responses are sharpened and made to control the operating time of a trigger circuit, whose average

output is metered. A sensitivity equal to 200 c. p. s. is obtained in the measure- ment of the frequency difference between two high Q cavities, whose resonance

frequencies are equal to 9000 Mc. Applications of this instrument are discussed,

especially those relating to measuring changes in dielectric constant. A simple

extension of the present instrument is suggested for simultaneously recording

changes in dielectric constant and loss. --Author's abstract.

Booker, H. G. and Gordon, W. E. , Outline of a theory of radio scattering in the

troposphere . Journal of Geophysical Research, Wash. ,D.C. , 55(3) -.241-246,

Sept. 1950. 2 figs. , 7 refs. , 9 eqs. DWB- -Observations in Caribbean Sea and

elsewhere showed that field strength well below the horizon decreased more

slowly than on diffraction theory and suffered violent fading. This is explained

by scattering from turbulence in the region of high field strength beyond the

horizon. (Met. Abs. 2. 5-5D--C. E. P. B.

Booker, H.G. and Gordon, W. E. , A theory of radio scattering in the troposphere.

Institute of Radio Engineers, N. Y. , Proceedings, 38(4):401-412, April 1950.

3 figs. , 12 refs. , 7 eqs. DLC --The theory of scattering by a turbulent medium

is applied to scattering of radio waves in the troposphere. Values of the scale

of turbulence and of the departure of refractive index from mean expected on

meteorological grounds are fully adequate to explain the scattered field strengths

observed experimentally. (Met. Abs. 8 1-75) --From authors' abstract.
22

E-93 Boyd, J. E. and Brown, F.B. (both, Ga. Inst, of Tech. ), Propagation of 3. 10 and

23 cm waves over a 50 mile optical path. Georgia Institute of Technology. State

Engineering Experiment Station, Contract W28-099-ac-175, Project 109-8, Technical Report No. 1, March 31, 1950. 69 p. 30 figs. (1 fold. ), table, 11 refs.

DWB--Experimental measurements of microwave propagation at X, S, and L bands

were over 30-60 mi land path in 1947 and 1948 to obtain data on the effect of

ducts, subsidence inversions and turbulence. The 100 day observations are analyzed and presented in statistical distribution curves. The results show that

(1) signal strength fluctuations of 20-30 deb are associated with atmospheric

stratifications and that (2) substandard layers may cause strong diffraction. (3)

Ray inversion in low level substandard layers may be a possible cause of some

large signal fluctuations. (4) Soundings show that ground based superrefracting

layers and ducts usually exist on radiation cooling nights, and that strong substandard layers may also develop during the early morning hours. (Met. Abs.

81-77)-- W.N.

E-94 Brandejs, Stanislav, Tabulky pro vypocet indexu lomu vzduchu v oboru ultrakratkych radiovln . (Table for calculating the air refractive index in the ultrashort

radio wave range. ) Meteorologicke Zpravy, 4(5-6): 107-108, 1950. Table, 3 refs.,

8 eqs. In Czech. MH-BH -Equations developed by H. G. BROKKER, A. FRIEND

and A.PERLAT are explained and a table for calculating the air refraction (dielectric constant) from temperature, pressure and humidity presented. For a more detailed study of the subject the author refers to his article on abnormal propagation

of ultrashort radio waves published in Meteorologicke Zpravy, 1947, p. 105.

(Met. Abs. 4. 10-267) -G.T.

E-95 Bremmer, H. , Voortplanting van radiogolven in de troposfeer. (Propagation of

radio waves in the troposphere.) Nederlands Tijdschrift voor Natuurkunde,

16(11) -.275-280, Nov. 1950. 4 figs. , 2 eqs. DLC -Discussion of superrefraction,

radio ducts and other aspects of radio wave reflection and propagation in the tro- posphere is illustrated by schematic diagrams and examples. (Met. Abs. 81-78)

-M.R.

E-96 Bullington, K. , Propagation of UHF and SHF waves beyond the horizon. Institute

of Radio Engineers, N. Y. , Proceedings, 38(10): 1221-1222, Oct. 1950. Fig. DLC -- Calculations by usual methods at above 200-500 Mc are severely limited by the uncertainty in choice of effective antenna heights. Clearance may be more important.

A useful parameter is the actual clearing divided by the height of the first Fresnel

zone. This ratio, as used to express diffraction loss over a knife edge and reflection from a plane surface, is graphically given. (Met. Abs. 8I-80)--W. N.

E-97 Bullington, K. , Radio propagation variations at VHF and UHF. Institute of Radio

Engineers, N. Y. , Proceedings, 38(l):27-32, Jan. 1950. 5 figs. , 8 refs. DLC--

The variation of received signal with location (shadow losses) and with time (fading) greatly affect both the usable service area and the required geographical

separation between co-channel stations. An empirical method is given for estimating the magnitude of these variations at VHF and UHF. These data indicate

that the required separation between co-channel stations is from 3 to 10 times the

average radius of the usable coverage, and depends on the type of service and on

the degree of reliability required. The application of this method is illustrated by

examples in the mobile radio-telephone field. (Met. Abs. 8 1-79) --Author's abstract.
23

Cheydleur, Raymond D. , A compilation of radio theses in American colleges and

universities. 1918-1950. Huntington, W.Virginia. Marshall College, Educational

Radio, 1950. --The 780 papers are listed alphabetically under 44 different subjects

and include 150 papers on electrical engineering, 42 on engineering, 1 on engineering mechanics, 5 on engineering and physics, 8 on mathematics and electrical

engineering, and 44 on physics. There are several papers related to the various

aspects of tropospheric propagation. The multigraphed bibliography includes

names of the 83 colleges and universities who responded with material and likewise, the 43 who did not. --W. N.

Cornell University. School of Electrical Engineering, Investigation of air-to-air

and air-to-ground electromagnetic propagation . Contract AF 33(038)-1091, Interim

Engineering Report No. 1-7, Dec. 27, 1948/Feb. 27, 1949 to April 27, 1950.

Also: Addendum to Report No. 4, June 27, 1949, and Supplement to Report No. 6, Jan. 27, 1950. 9 pieces. Figs. , refs. , eqs. Several pieces typescript or photostat of typescript. DWB--The following papers are reviewed: Craig, R. A. , The

meteorology of ducts ; Trolese, L.G. , Tropospheric propagation characteristics ; Brooks, F. E. and others, Dielectric constant measurements ; Hastings, C.E. , Variation in velocity of radio propagation ; Boyd, J. E. , Propagation of 3-10, and

25 cm waves over 50 mile optical and non-optical paths ; Stratton, --- and La Grove,

---, Angle of arrival at low angle of incidence ; and other papers. (Met. Abs.

8I-83)--M.R.

Crain, Cullen Malone, Apparatus for recording fluctuations in the refractive

index of the atmosphere at 3. 2 cm wavelength. Review of Scientific Instruments,

N. Y. , 21(5):456-457, May 1950. 2 figs. , 4 refs. DLC--An apparatus for the

study of microwave propagation is presented which will accurately record small

changes in the refractive index of the atmosphere. The equipment is a modification of that previously used for measuring the dielectric constants of several

gases under controlled conditions. --E. K.

Crain, CM. and Gerhardt, J. R. , Measurements of the parameters involved in

the theory of radio scattering in the troposphere. Texas, University, Electrical

Engineering Research Laboratory, Contract N5 ori- 136, Report No. 47, Nov. 30,

1950. 22 p. 11 figs. , table, 8 refs. DWB--Micrometeorological studies, using

a recording refractometer and bead type thermistor, have been made since 1948

at the University of Texas to determine refractive index in lowest 50 ft of the

atmosphere. Traces are presented to show simultaneous recording of refraction

index (for microwave transmission at 1, 2, 3, 12 and 32 ft above dry and moist

ground and with varying weather conditions and temperature fluctuations).

Refractive index related to small scale turbulence, stability, etc. Future program outlined. (Met. Abs. 3. 4-7D--M. R.

Crain, CM. and Gerhardt, J. R. , Some preliminary studies of the rapid variations

in the index of refraction of atmospheric air at microwave frequencies. American

Meteorological Society, Bulletin, 31(9):330-335, Nov. 1950. 7 figs. , 11 refs. , 2 eqs. MH-BH--Rapid moisture variations in the atmosphere are measured by the

dielectric constant or index of refraction of atmospheric air at microwave frequencies. The theoretical basis for this procedure is discussed. The apparatus used

to measure small changes in refractive index as a function of atmospheric moisture

compares the resonant frequency of a cavity through which air is drawn with the

constant resonant frequency of a sealed reference cavity. An auxiliary bead

thermistor and heated platinum wire were used for comparing variations in refractive
24

index with those of air temperature and wind speed. A comparison of simultaneously recorded fluctuations of microwave index of refraction and air temperature

shows that air temperature and moisture variations are positively correlated. This

positive correlation is shown to be a function of soil moisture, elevation and insolation. No immediate correlation was found between refractive index and wind

soeed. (Met. Abs. 2. 6-145)-I.L. D.

E-103 Fok, V. A. , Teoriia rasprostraneniia radiovoln v neodnorodnoi atmosfere dlia

pripodniatogo istochnika. (Theory of radio wave propagation in inhomogeneous

atmosphere for an elevated transmitter.) Akademiia Nauk SSSR, Ser. Fizicheskaia,

14(l):70-94, Jan/Feb. 1950. Fig., 4 refs. , numerous eqs. DLC -In two earlier

papers the author worked out the theories of radio wave propagation, a) in an at- mosphere whose dielectric constant varies with height, for a transmitter on the

ground, and b) for an elevated transmitter in a dielectrically homogeneous atmosphere, respectively. In the present paper the case of an elevated transmitter in an inhomogeneous atmosphere is considered. The theory is also applied to the

problem of superrefraction. --G.T.

E-104 Gibson, Theodore W. , Jr. , Meteorological aspects of radio propagation. Weatherwise, Boston, 3(2):32-34, April 1950. 4 figs. DWB--Brief explanation of the

effect of varying lapse rates of humidity and temperature on normal and anomalous

propagation of microwaves (television and FM). (Met. Abs. 8I-85)--M.R.

E-105 Green, James W. , On the deduction of the refractive index profile of a stratified

atmosphere from radio field strength measurements . Institute of Radio Engineers,

N. Y. , Proceedings, 38(l):80-88, Jan. 1950. 9 figs. , 8 refs. , 7 eqs. DLC--This

academic discussion on MACFARLANE's theory concludes that, except for the possible exception of a limited frequency range under linear lapse rate conditions, the

method is too sensitive to permit application directly to experimental data.

(Met. Abs. 9. 11-169) --W.N.

E-106 Heightman, D. W. , Propagation of metric waves beyond optical ranges . British

Institution of Radio Engineers, London, Journal, 10:295-311, Oct. 1950. DLC--

This paper was awarded the Clerk Maxwell Premium for 1950. It gives a qualitative survey of tropospheric and ionospheric propagation in the frequency band

30-200 Mc/s. Theoretical considerations are limited to explanations of the basic

principles involved. A knowledge of the easily recognized meteorological conditions associated with variations in tropospheric propagation is shown to be useful

in short term prediction of radio conditions. Long term observations over various

land and sea paths, both tropospheric and ionospheric, are presented in graphical

form and results discussed. --Brit. IRE abstract.

E-107 Jones, R.F. , Low level atmospheric ducts . Nature, London, 165(4207): 971,

June 17, 1950. DLC--Short wave radio ducts across Cardigan Bay occurred in air

which had travelled mostly over land. No signals in warm sector air from far to southwest. (Met. Abs. 8I-86)--C. E. P. B.

E-108 Karp, Samuel and Sollfrey, William, Diffraction by a dielectric wedge; with application to propagation through a cold front. New York Univ. , Mathematics

Research Group, Research Report No. EM-23, Oct. 1950. 45 leaves. 13 figs. , 10 refs. , 7 eqs. Mimeo. DWB--
25

The fields diffracted by a dielectric wedge whose dielectric constant differs but

slightly from that of its surroundings have been obtained by an approximate method.

The fields are expanded in powers of the difference in dielectric constant and only

first powers are retained. The approximate fields are then represented as a superposition of plane waves of arbitrary complex direction of propagation, and the re- sulting integrals evaluated by stationary phase to obtain the asymptotic form of

the scattered fields. The reflected and transmitted plane waves agree with those

obtained by geometrical optics, and the angular pattern of the diffracted cylindrical

waves is found. The results are applied to the propagation of plane waves through

a cold front. (Met. Abs. 8 1-87) --Authors' abstract.

E-109 Knighting, E. , Elements of anomalous radio propagation. Meteorological Magazine, London, 79(933): 74-81, March 1950. 4 figs. , 6 photos, 5 refs. , 4 eqs.

DWB--The derivation of a "Modified Refractive Index" (MRI) is stated and it is

shown that the conditions necessary to bend a short wave radio beam downward

are a temperature inversion and/or a lapse rate of mixing ratio such that: Temperature gradient (°F per 1000 ft)/7+2 Humidity lapse (gm kg per 100 ft)/3 exceeds

1. Observations show that this condition frequently holds, especially over the

sea, over a layer ("Duct") on or near the earth's surface. Illustrations of calculated MRI curves are given, and the tracks of beams through or under a duct.

Application of electromagnetic wave theory shows why shorter wave lengths are the more affected by super-refraction. (Met. Abs. 8l-89)--C. E. P. B.

E-110 Megaw, E.C.S., Scattering of electromagnetic waves by atmospheric turbulence . Nature, London, 166(4235): 1100-1104, Dec. 1950. Figs., 2 tables, 18 and 7 refs.

DLC--In the first section of the paper the stellar scintillation and the spectrum of

turbulence in the free atmosphere is discussed. The second section is the treat- ment of scattering of short radio waves by atmospheric turbulence. Experiments

lead to the conclusion that, in spite of apparent discrepancies, the anomalous

observations had a common cause, not in any exceptional condition of the atmosphere but in its permanently turbulent state and in the consequent fluctuation of

refractive index. --E. K.

E-lll Millar, J. Z. and Byam, L.A. , Jr. , A microwave propagation test . Institute of

Radio Engineers, N. Y. , Proceedings, 38(6):619-626, June 1950. 13 figs. , 2 tables. DLC --Description of a microwave test conducted for a year (1946-47)

with simultaneous transmissions on 16. 2-7. 2 and 3. 1 cm wavelengths over an

unobstructed overland path (Neshanic to New York). Curves show relative field

strength. Seasonal (summer and winter) and hourly variations in fading are shown

and discussed in connection with weather conditions. (Met. Abs. 8I-9D--W. N.

E-112 Milnes, B. and Unwin, R.S., A radio meteorological investigation in the South

Island of New Zealand. Physical Society of London, Proceedings, Ser. B, 63(8):

595-616, Aug. 1, 1950. 26 figs. , 9 refs. DWB--The inversion that results when

fohn winds blow out over the sea near Canterbury Bight has a pronounced effect on radio transmission. Meteorological factors and transmission measurements

are analyzed. Some lapse rate and field strength contour charts are given.

(Met. Abs. 81-92).
26

E-113 Parke, Nathan Grier, III, Microwaves in an irregular atmosphere. Contract AF

19(122)-91, Interim Reports, No. 1-3, Sept. 30-July 15, 1950. 3 pieces. Tables,

refs. , eqs. (Third interim report has subtitle: Scattering by discrete distribu - tions. ) DWB--In the first phase of the project a survey of previous work on tropospheric propagation of microwaves was made. The author's theoretical work on

Matrix optics was extended and adapted to the scattering problem for short waves. An approximation was developed for the quasi-stationary case. In the second

phase, the algebra was worked out for relating the scattering of microwaves to the conditions existing in a turbulent atmosphere. Using dipoles as the basic

elements, general expressions are derived for the power received from dipole distribution, and the results are applied to case of reception of radiation scattered

by a cloud of fluctuating electric susceptibility. The formula W(S, t)= (VKvrr

(4 OR) )W o (s,t), where W is the scattered power and (j is the Fourier trans- form of the space autocorrelation of the electric susceptibility, was obtained. In the last stage the problem of scattering by discrete distributions of scatterers

was considered. Six models were analyzed, in which the scatterers were static,

dielectric spheres. Then the problems of moving scatterers, and the theory tested

against the specific problem of falling rain. The spectrum of radiation returned by

rain when observed looking vertically upward is determined, illustrated and described. (Met. Abs. 8I-93)--From author's abstract.

E-114 Perlat, A. , Effet des conditions meteoroloqiques sur la propagation des ondes

radioelectriques a frequence elevee . (Effect of meteorological conditions on the

propagation of radioelectric waves of high frequency. ) Journal Scientifique de la

Meteorologie, Paris, 2(8):101-107, Oct. /Dec. 1950. 3 figs. French, English

and Spanish summaries p. 101. DWB--Test conducted in 1948 and 1949 between

Paris and Clacton on Sea (Eng. ) show that anomalous reception of 2 m radar

signals depends on the presence of a subsidence inversion over the area and the

absence of any fronts along the course. Best reception (at distance of 400 km) occurs when pressure is above 1013 mb and dew point above 9°C. Surface observations and radiosonde data were analyzed for 52 cases during the year when long

distance reception was possible. (Met. Abs. 8I-94)--M.R.

E-115 Phillips, W.Eric, The permittivity of air at a wavelength of 10 centimeters . Institute of Radio Engineers, N. Y. , Proceedings, 38(l):786-790, July 1950.

5 figs. , 3 tables, 16 refs. DWB--Observed values of permittivity of moist air

under various conditions of temperature, water vapor content and pressure are

in agreement with theoretical static values and confirm belief that water vapor

is very important in atmospheric refraction or anomalous propagation of centimeter-radio waves. Wavemeter and method of measurement described. Tables

show results of measurement of dry air at sea level and at reduced pressure, of

saturated air and of moist air. Work done is preliminary to long term program of

correlating meteorological conditions with microwave propagation off the coast

of Natal. (Met. Abs. 8I-95)--M.R.

E-116 Pickard, Greenleaf W. and Stetson, Harlan T. , Comparison of tropospheric reception at 44. 1 mc. and at 92. 1 mc. over the 167 miles path. Alpine. New Jersey to Needham, Massachusetts 1947-1948. Journal of Atmospheric and Terrestrial

Physics, London, l(l):32-36, 1950. 4 figs. , 2 refs. MH-BH--Daily and hourly

field intensities of transmissions show close correlation with index of refraction

of radio waves computed from pressure, temperature and humidity at Boston, Mass.

Frequency distribution of reception in decibels is analyzed. Transmission is

mainly due to refraction in the lower atmosphere. (Met. Abs. 3. 2-20D--C.E.P.B.
27

117 Satow, P. G. , Marine navigation, radar, meteorology and charts. Marine Observer,

London, 20(149): 158-167, July 1950. 2 figs. , photo. DLC--Includes notes on subrefraction and super-refraction due to meteorological causes. (Met. Abs. 10-7).

-118 Saxton, J. A. , Reflection coefficient of snow and ice at V.H.F. Wireless Engineer, 27(316): 17-25, Jan. 1950. 13 figs. , table, 10 refs. , 22 eqs. 2 append.

DLC--Discussion of the nature and composition of snow, the dielectric properties

of snow, land and sea at 30, 300, 3000 and 30,000 Mc/s, and the effects of

multiple reflection phenomena in changing the vertical coverage diagram of a very

high frequency radio transmitter. Reflection coefficients for plane waves under

the above conditions given in equations, tables and nomograms. (Met. Abs.

7-99) -M.R.

-119 Smith-Rose, R.L. , The speed of radio waves and its importance in some applications. Institute of Radio Engineers, N. Y. , Proceedings, 38(l):16-20, Jan. 1950.

2 tables, 16 refs. DLC--The present knowledge of the subject is discussed and

summarized. A table furnishes the measurements of type of waves, frequency,

transmission, mean value in km/s accuracy, and the names of the workers.

Influence of the refractive index upon speed of waves is considered. (Met. Abs.

8 1-97) -W.N.

120 Straiton, A. W. and Smith, H. W. , Progress of microwave radio scintillations at wind speed on an overwater path. Institute of Radio Engineers, N. Y. , Proceedings, 38(7): 825-826, July 1950. Fig., 2 tables, 3 refs. DLC -Brief report and

results of a 2 way analysis of the experimental transmission of 3. 2 cm wave over

the 26 mi path in the Gulf of Mexico during June and July 1949 are given here. It is indicated that the scintillations were rather due to regions of different electric

constant moving across the path, than to additional signals from scattering areas

outside the duct. (Met. Abs. 8I-98)-W. N.

• 121 Stranz, Dietrich, Meteorologie und Mikrowellenausbreitung. (Meteorology and

propagation of microwaves. ) Meteorologische Rundschau, 3(9/10) -.199-202,

Sept. /Oct. 1950. 2 figs. , 2 tables, 20 refs. , eqs. DWB-After a historical

introduction, author applies laws of optics to calculations of paths of radio

beams for various refractive indices and degrees of absorption. The dimensions

of the factors are of the same order as those of small discontinuities in the tro- posphere. Finally, a reference is made to "radioclimatology ". (Met. Abs.

8I-99)-C.E.P.B.

122 Swingle, Donald M. , Nomograms for the computation of tropospheric refractive

index, its gradients and discontinuities . Harvard Univ. Cruft Lab. , Contract

N5ori-76, Task Order No. 28, Technical Report, No. 102, Feb. 25, 1950. 15

leaves. 3 figs. , table, 24 refs. , 28 eqs. MH-BH—Index of refraction n of moist

air is given by

(n-1) X106

= 3%*- <P + 1? 73e)

valid for electromagnetic waves down to 1. 5 cm. Three sets of nomograms are given, designed for use with radiosonde ascents: (1) for refractive index in terms
28

of density of atmospheric gases and dew point, (2) for discontinuities due to discontinuities of air temperature and dew point, and (3) for gradients of refractive

index in terms of gradients of temperature and dew point. (Met. Abs. 81-100)

-C.E.P.B.

E-123 Yerg, Donald G. , The importance of water vapor in microwave propagation at temperatures below freezing. American Meteorological Society, Bulletin, 31(5):

175-177, May 1950. 5 figs. , ta'ole, 2 refs. , 4 eqs. DWB--Nomograms show

contribution of vapor pressure to refractive index at various temperatures (0° to -40° C), and to dn/dh (slope of the index curve) for temperature inversions in a saturated atmosphere. Modified index-of-refraction curves computed by neglecting and then by including vapor pressure as obtained from radiosonde flights at Fairbanks and Bethel. Conclusion is that vapor pressure cannot be neglected at temperatures above -35°C. (Met. Abs. 8I-10D--M.R.

1951

E-124 Baldinger, E. and Schaetti, N. , 9. Generalversammlung der Union Radio-Scientifigue Internationale (U. R.S.I.) in Zurich (vom 11. -22. September 1950). (Ninth

general meeting of the International Scientific Radio Union (U. R.S.I.) in Zurich

(Sept. 11-22, 1950).) Zeitschrift Kit Angewandte Mathematik und Physik, 2(3):

212-214, May 15, 1951. DLC--A brief report of the meeting including recommendations for further investigations to the following Commissions: II. Propagation

in the troposphere (further investigation of influence of latitude, nature of ground

and climate on refractive index, especially for short waves); III. Ionosphere and

propagation of waves; IV. ,V. Radio noises of terrestrial origin. (Met. Abs.

8I-102)--C.E.P.B.

E-125 Birnbaum, George, Fluctuations in the refractive index of the atmosphere at microwave frequencies. Physical Review, N. Y. , 82(1):110-111, April 1951.

2 figs. , 6 refs. , 3 eqs. DLC --Brief note on experimental observations as con- ducted with the aid of a refractometer developed and located at National Bureau

of Standards, Wash. , D.C. The difference in recording with one or both cavities

of the instrument open to air is shown graphically. (Met. Abs. 8 1-103) --W. N.

E-126 Booker, Henry George (Cornell Univ. ), Meteorological aspects of propagation

problems. (In: Compendium of meteorology. Boston, American Meteorological

Society, 1951. p. 1290-1296. 3 figs. , 20 refs. , 5 eqs.) DWB-The phenomenon

of superrefraction or extra downward refraction in which the downward refraction

of radio waves exceeds the curvature of the earth, as experienced at radar sta- tions is described and the regions in which this phenomenon has been observed

are listed. An explanation of the origin of superrefraction in terms of the temperature excess and of the humidity deficit of the appropriate air mass in relation

to the earth's surface is presented. The problem of specifying accurately the

temperature and humidity gradients and other meteorological data from generally

available synoptic data and the meteorological factors responsible for these gradients are discussed. Some of the meteorological investigations made by R. A.

CRAIG and H.G.BOOKER on the measurement of temperature and humidity at various heights and the explanation of their distribution by a theory of the modification in air mass by eddy diffusion, are summarized. (Met. Abs. 81-104)

--I.L.D.
29

E-127 Boyd, J. E. (Ga. Inst, of Tech. ), The effect of atmospheric conditions on the pro- pagation characteristics of electromagnetic waves in the microwave region. Georgia Institute of Technology. State Engineering Experiment Station, Contract

W28-099-ac-175, Project 109-8, Technical Report, No. 4, Final Report on Project,

June 30, 1951. 91 p. Diagr. , graphs, 10 refs. DWB-During 1947, 1948 and

1949 the signal strength for optical and nonoptical links (at frequencies of 1310,

2860 and 9400 Mc) over highly varying and rough terrain were intensively studied,

stressing the meteorological influence on microwave propagation, particularly the

effects of ducts, inversions and turbulence. Data on refracting conditions were

obtained by aircraft and balloon soundings and by radiosondes and modern electronic apparatus. Measurements up to 100 ft above the surface were taken with

a meteorological tower sounding system. The valuable results are analyzed and

discussed, concluding with the desirability of further intensive investigations

of the important problem of the atmospheric structure within the first hundred feet

above the earth's surface, and of the effect of irregular ground on signal stability.

(Met. Abs. 8I-105)--W. N.

E-128 Brocks, Karl, Probleme der "Radiometeorologie". (Problems of radio-meteorology)

Annalen der Meteorologie, 4(l/6):78-86, 1951. 2 figs. , table, 17 refs. , 4 eqs.

Summaries in German and English p. 78. DWB--A discussion of the effect of the

atmosphere on radio waves 1 cm to 10 m. The equations of the "relative beamcurvature" (negative gradient of refractive index times earth's radius) are set out

and constants of pressure and vertical gradients of temperature and humidity tabulated. Other measures of refraction in use are defined. Diurnal variations at Quickborn are discussed. (Met. Abs. 8I-106)--C. E. P. B.

E-129 Cornell University. School of Electrical Engineering, Bibliography of report on

tropospheric propagation Contract AF 33(033)-1091, Final Report, Pt. 1, April

1, 1951. Each section renumbered. DLC--A thoroughly annotated bibliography

of 867 reports on 17 phases of troposphere radio propagation from numerous

American, British, Australian, Canadian and New Zealand sources from 1930 to 1949. The only sources other than those from the English language that have

been abstracted are those which have been translated by such agencies as CADO

and NACA. The abstracts are thorough and contain essential information and

theory. A detailed subject and author index is provided. The meteorological

theory and instrumentation, effect of temperature and humidity inversions, hills,

trees, storms, polarization, etc. , are all given proper emphasis. The term

Radio climatology is introduced here. (Met. Abs. 4. 7-226)--M. R.

E-130 Cornell Univ. School of Electrical Engineering, Summary report, air-to-air and

air-to-ground electromagnetic propagation . Contract AF 33(038) -1091, Final

Report, Pt. 2, June 1, 1951. 109 p. tables, figs. , eqs. DWB--The present

state of knowledge on propagation of electromagnetic waves above 30 Mc/s is

reviewed and summarized under the following headings: 1) An evaluation of

radio wave propagation problems with emphasis on air-to-air and air-go-ground

transmission; 2) Standard and non-standard atmosphere propagation — pure

theory; 3) Propagation experiments; 4) Meteorological theory, experiment and

equipment; 5) Radar forecasting; 6) Absorption and scattering; 7) Dielectric

constant and loss factor; 8) Reflection coefficient; 9) Horizontal and vertical

polarization; 10) Effects of hills, trees and other obstacles; 11) Air-to-air

and air-to-ground propagation. References to earlier work and definitions of

the topics are included. (Met. Abs. 8I-108)--W. N.
30

E-131 Cornell Univ. School of Electrical Engineering, Investigation of air-to-air and

air-to-ground experimental data . Contract AF 33(038) -1091, Final Report, Pt. 3,

Dec. 10, 1951. 182 p. Numerous figs. , tables, eqs. DWB- -Attempts to obtain

the true shape of the refractive index profile from a model of a horizontally stratified atmosphere and from radio data yield valuable information on characteristics

without solving the problem. A wave structure is suggested and a theory of the

elevated layers predicts satisfactorily the radio holes and to some degree the

interference regions by means of statistical analysis. A method for computing

the field strength in a standard atmosphere for communication (above 30 Mc/s)

between two aircraft at the same altitude over land is presented. It is suggested

that one plane should stay below 5000 ft because of the radio holes (24 of 27

runs above 5000 ft contained radio holes). (Met. Abs. 8I-109)--W. N.

E-132 Cornell Univ. School of Electrical Engineering, Air-to-air radio wave propagation

data. Contract AF 33(038)-1091, Final Report, Pt. 4, Dec. 10, 1951. 139 p. Numerous graphs, 2 figs. DWB--The individual records and data of 22 flights are presented. The meteorological conditions for each flight are given, and a brief

description of radio and meteorological instrumentation is included. The field

strength (in most cases) was plotted as a function of distance, including the distance between two aircraft taking off from Wright -Patterson Air Force Base, meeting and then separating for a determined flight -distance at equal speed to keep

the center point fixed at a constant altitude. The theoretical curves presented,

involved geometrical optics to a stratified atmosphere. Reflection coefficients were compared to theoretical values for each flight. The use of the form for analysis and estimation of the refractive index is demonstrated. The results are summarized in Final Report, Pt. III. (Met. Abs. 8I-110)--W. N.

E-133 Feinstein, J. , Tropospheric propagation beyond the horizon. Journal of Applied

Physics, 22(10): 1292-1293, Oct. 1951. Fig., 5 refs. , eq. DWB--Since the

atmosphere possesses a gradient of refractive index, a partial reflection of wave

energy is delivered beyond the horizon of the transmitter. To estimate the magnitude of the field produced by that reflection, from a hybrid ray and wave theory,

is the purpose of this paper. (Met. Abs. 4. 1-272) --W. N.

E-134 Friedman, Bernard, Propagation in a non-homogeneous atmosphere . Pure and

Applied Mathematics, 4(2/3) :317-350, Aug. 1951. 3 figs. , 16 refs. , 96 eqs.

DWB--Two previous approaches to the problem of microwave propagation around

the earth (that of WATSON, RYDBECK and others, and that of PRYCE, BOOKER,

FURRY and PEKERIS) are reviewed. In this substantial theoretical paper, a

third fundamental assumption is used as an approach. Starting with Maxwell's

equations, the theory is developed for propagation in an inhomogeneous atmosphere where the dielectric constant is radially stratified. This allows treat- ment for a uniform and a non-uniform atmosphere, and results compare favorably

with those obtained for a "flat earth" by the W. K.B. method, except where large

distances exist between transmitter and receiver. Finally, the theory is applied

to an atmosphere containing a duct, and a comparison made between the previous

theory based on a magnetic dipole, and the corresponding equations for an electric dipole. (Met. Abs. 4. 7-227)-M. R.

E-135 Gerks, Irvin H. , Propagation at 412 megacycles from a high power transmitter.

Institute of Radio Engineers, N. Y. , Proceedings, 39(11): 1374-1382, Nov. 1951.

14 figs. , table, 17 refs. , eq. DLC--During the summer of 1948 and fall, winter
31

and spring of 1949-1950, measurements taken over rolling midwestern terrain

(about 100 mi distance) indicate: (1) the existence of pronounced nocturnal

superrefraction during summer, and (2) of persistent scattering by atmospheric

turbulence near the surface in all seasons. Graphs show the effect of distance,

terrain, antenna height and time on field strength. Finally, the significance of

the results in relation to electromagnetic wave communication is indicated.

(Met. Abs. 8I-115)--W. N.

E-136 Germany. Deutscher Wetterdienst in der US -Zone. Wetterdienstbibliothek,

Literatur-Ausstellung uber Fragen auf dem Gebiet der Ausbreitung elektrischer

Wellen vom Standpunkt der Meteorolocrie aus . (Presentation of literature on oroblems in the field of electrical wave propagation from a meteorological point

of view. ) (1951?) 3 p. Mimeo. DWB--Four brief bibliographies are included,

covering the following subjects applicable to the general subject of electromagnetic propagation: 1) The influence of the atmosphere on electric waves (17

items); 2) Thunderstorms (13 items); 3) Temperature and humidity in the lowest

kilometer of the atmosphere (16 items); and 4) Pertinent German works on various

fields of meteorology and forestry (10 items). (Met. Abs. 8I-116)--M. R.

E-137 Gough, M.V. , Propagazione delle onde metriche (VHF) e decimetriche (UHF)

entro il campo ottico . (Propagation of meter (VHF) waves and decimeter (UHF)

waves within the optical range. ) Marconi, Rome, 2(3/4):21-32, July/Dec. 1951.

DLC --Ground reflection and its dominant influences on VHF and UHF propagation

in the optical range is treated in some detail here. Other influencing factors

such as atmospheric refraction, ionospheric and tropospheric reflections and diffraction are noted briefly. (Met. Abs. 8I-117)--W. N.

E-138 Grosskopf, J. , Ultrakurzwellenausbreitung im Bereich von 30 bis 100 MHz. I. (USW propagation in the 30-100 Mc/s range, Pt. 1.) NTZ: Nachrichtentechnische Zeitschrift, Berlin, 4(9):411-414, Sept. 1951. Pt. 2, Ibid. , 4(10):441-

451, Oct. 1951. 30 figs. , 46 eqs. , 2 refs. DLC -Field strength measurements

made by the German Post Office over distances within the range of vision are analyzed. Factors investigated include the influence of ground reflections near

transmitter or receiver on the shape of the field, the influence of undulations or hilliness on attenuation, and the diffracting effect of obstacles. Irregularities

in the field strength/distance curves are traced to relatively simple causes such

as double reflections. Diffraction measurements indicate that in general the

classical diffraction formulas are inapplicable, and that the analysis of the propagation process must take account of the nature of the terrain.

E-139 Hauer, A. , Meteorologische aspecten van de voorplanting in de atmosfeer van

zeer korte golven. (Meteorological aspects of very short wave propagation in

the atmosphere.) Tijdschrift van het Nederlandsch Radiogenootschap, Baarn,

16(l):39-52, Jan. 1951. 6 figs. , 4 refs. , eqs. -This lecture, which deals with

some practical measurements held against the theory of refraction and scattering

related to meteorological factors, was delivered before the Nederlandsch Radiogenootschap, Oct. 1950. --W. N.
32

E-140 Hay, H. G. and Unwin, R.S., Extension of the mode theory of tropospheric refraction to cover variations in the refractive index profile along a transmission path.

Great Gritain. Telecommunications Research Establishment, T. R.E. Technical

Note, No. 124, Aug. 1951. 13 p. 6 figs. , 3 refs. , 37 eqs. Mimeo. GB-MO--

The method is to divide the transmission path into zones in each of which variations in the profile are small. The duct height and lapse rate of modified refractive index at infinite height are found by the half-power law and used with a set

of curves to evaluate the distribution of radio field strength beyond the horizon

of the transmitter. (Met. Abs. 6. 5-102)--C. E. P. B.

E-141 Hines, CO., Wave packets, the Poynting vector, and energy flow, Pt. 1. Nondissipative (anisotropic) homogeneous media. Pt. 2, Group propagation through

dissipative isotropic media. Pt. 3, Packet propagation through dissipative anisotropic media. Journal of Geophysical Research, 56(1, 2): 63-72; 197-220, March,

June, 1951. 15 refs. , 131 eqs. DWB--An attempt to correlate the results of

electromagnetic propagation energy velocities obtained by the wave packet and

the POYNTING vector by the energy density does not equal the speed obtained by

the packet method. The first paper deals with nondissipative method in which

the effective permittivity matrix is Hermitian. When plane homogeneous waves

are propagated through a homogeneous, nonabsorbing media, agreement is good

for direction in which energy flows. In the second paper, the expression for

velocity of a wave packet or group speed in a dissipative isotropic medium was

found to be U - c/(dkn2/dk) where n, is the real part of the refractive index at frequency kc/2 It . Expressions are also obtained which apply to transmissions

of pulses through slabs of material. In the third paper formulas are proposed for

expressing the velocity of a packet in an anisotropic dissipative medium. One

expression is given for homogeneous waves and one for inhomogeneous waves.

In the case of nondissipative media, the two are shown to be equal. (Met. Abs.

8I-118)»M.R.

E-142 Jones, E.H. , Propagation of VHF radio waves. Nature, London, 168(4281) :870-

871, Nov. 17, 1951. 2 figs. DLC, DWB--Note on some field strength measure- ments on frequencies of 280 and 387 Mc/s over distances up to 250 mi, the

transmitter being airborne at 40, 000 ft and the receiver near the ground. Some

discrepancies between observed and calculated values are noted.

E-143 Kerr, Donald E. (ed. ), Propagation of short radio waves. 1st ed. Prepared under

the supervision of the Office of the Scientific Research and Development, National

Defense Research Committee. N. Y. , McGraw-Hill, 1951. 728 p. 299 figs.

(Massachusetts Institute of Technology, Radiation Laboratory Series, No. 13).

DLC --The book discusses and treats radio meteorology with many experiments of

correlating radio meteorological patterns, and will be found handy as a reference on tropospheric propagation. The chapters are: Elements of the problem; Theory

of propagation in a horizontally stratified atmosphere; Meteorology of the refraction problem; Experimental studies of refraction; Reflections from the earth's

surface; Radar targets and echoes and Meteorological echoes and atmospheric

attenuation. (Met. Abs. 8I-119)--W. N.

E-144 Knighting, E. , Some meteorological aspects of radio duct formation. Physical

Society of London, Proceedings, Sec. B, 64(373) :21-30, Jan. 1951. DLC--

Theoretical discussion of three problems of meteorological interest concerning

formation of radio ducts in the atmosphere, which occurs when variation of
33

height of modified refractive index obeys certain conditions: 1) considerations

of growth rate of ducts over sea, 2) duct formation during nocturnal cooling, and

3) duct widths associated with power law profile of modified refractive index.

(Met. Abs. 8I-120)--Author's abstract.

E-145 New Zealand. Dept. of Scientific and Industrial Research, Report of the factual

data from the Canterbury Project, a radio-meteorological investigation in the

South Island of New Zealand. London, pub. by the Dept. , 1951. 3 vol. (857 + 187 p. ) Figs., tables, graphs, refs. V. 2-3 oversize. DWB- -These three large

volumes comprise the final report, including all of the data, charts and analyses

of a joint scientific investigation conducted between Sept. 1946 and Dec. 1947 by

the Dept. of Scientific and Industrial Research of the United Kingdom and of New

Zealand. The "Canterbury Project" was planned in 1944 to provide information on the formation and behavior of low level atmospheric ducts caused by advection

of warm dry continental air over the neighboring sea. An area in Canterbury Province of South Island, New Zealand was considered the most suitable. Vol. 1,

Descriptive and numerical data , contains an analysis of all of the meteorological

and radio data collected during this period and all of the detailed surface, upper

air, synoptic and oceanographic data for the entire area around New Zealand.

Airplane, radar, balloon, radiosonde and ship observations were used intensively

and extensively. Each separate situation is described and analyzed. Surface

(coded) synoptic observations are given for 00, 03, 06, 09, 12, 15 and 18 h for a score of stations. The observational, operational and theoretical considerations are also treated at great length and in detail. Vol. 2, Meteorological

data, consists of a large "atlas" type presentation of graphs and charts prepared from the meteorological data collected during this survey. A detailed

topographical map of the region and a cross section showing the relief in relation to observation stations is followed by detailed isopleth and sounding diagrams of potential temperature, specific humidity, temperature and upper air

winds for levels from the sea level to 2000 ft height. Actual anemograph traces

for the 50 ft level are reproduced for several stations for each of the 50 or so

situations studied. Synoptic charts are presented for 1200 h local time for the

Australasian region for all of the periods when data were obtained. Isopleth cross sections of potential temperature and specific humidity are given in great

detail for a range of 25 mi of land and 120 mi at sea (to 1000 ft). Soundings

are given for both land and sea. Vol. 3, Radiowave propagation data, also

consists of large detailed graphs and isopleth cross sections of modified re- fractive index, height gain curves, etc. , from aircraft and ship soundings from

to 1000 or 2000 ft height. About 50 separate situations are thoroughly ana- lyzed in this fashion. (Met. Abs. 8I-12D--M. R.

E-146 Overcash, Frank J. (Aircraft Radiation Lab. , Wright Air Dev. Center), Index of

refraction measurement with an airplane psychrograph. U. S. Air Force, A.F.

Technical Report, No. 6621, Aug. 1951. 38 p. 33 figs. , 10 refs. DWB--An

airplane psychrograph was used by the Aircraft Radiation Laboratory of Wright

Air Development Center to obtain accurately the atmospheric index of refraction up to 10,000 ft in the Dayton, Ohio, area. Complete details of its use

are given, with curves of experimental results. This instrument makes a con- tinuous recording of the fine detail of the wet bulb and dry bulb temperature

above freezing, which is used with pressure to calculate index of refraction.

These data show that the index profile follows closely the wet bulb temperature

profile in the Dayton, Ohio, area in the summer months. Index lapse rates

greater than 30(n-l)106 units per 100 ft were recorded at 7000 ft. Actual index curves that conform approximately to what has been considered the standard were found to be the exception rather than the rule. (Met. Abs. 81-122)--

Author's abstract.
34

E-147 Perers, Olaf F. ; Stjernberg, Bo. K.E. and Forsgren, K.H. , Microwave propagation in the optical range . Gcleborg, Sweden. Chalmers Tekniska Hogskola,

Handlingar, No. 108, 1951. 19 p. Graphs, photos, refs. Price: Kroner 3-. DWB--In 1946 when these propagation tests betan in the vicinity of Goteborg,

Sweden, access to reports on similar works by foreign scientists was not possible. The results presented are nevertheless valuable for studying the influ- ence of local weather and consist of: transmission field strength, attenuation,

refraction, fading and diurnal variation of 10, 3, and 1 cm wavelengths.

Equipment, sites of installations and records are shown in photographs.

(Met. Abs. 8I-124)-W. N.

E-148 Phillips, W.Eric; Ashwell, P.C.and Browne, L.C. (all, Univ. of Natal, Durban),

Atmospheric super-refraction and the anomalous propagation of radio waves off the coast of Natal. South African Journal of Science, 48(5): 163-166, Dec. 1951.

2 figs. , 7 refs. DWB- -Correlated meteorological observations with microwave

phenomena on the Natal coast of Wentworth and Durban, showed that superrefraction is present during the autumn and winter months. Some ducts were

transitory. The K-H layer plays no role in such propagation. Some data are given. (Met. Abs. 4. 5-241) -W. N.

E-149 Saxton, J. A. , The propagation of meter radio waves beyond the normal horizon.

Pt. 1. Some theoretical considerations with particular reference to propagation

over land . Institution of Electrical Engineers, N. Y. , Proceedings, Pt. III. 98(55) :360-369, Sept. 1951. 15 figs. , table, 14 refs. , 13 eqs. Also: Saxton,

J. A.; Luscombe, G. W. and Bazzard, G.H. , Pt. 2, Experimental investigations

at freguencies of 90 and 45 Mc/s . Ibid., 98(55): 370-378, Sept. 1951. 12 figs.,

table, 5 refs. DLC--In Pt. 1, the relative importance of abnormally high refraction near the surface of the earth, and of reflection from high level inversion

layers, is investigated and illustrated by examples. Of the two mechanisms,

the latter is the more likely to give abnormally high field strength at ranges of a few hundred kilometers, especially for low terminal heights. Consideration

is also given to the effects of scattering by turbulent eddies in the atmosphere.

This is of less importance than other mechanisms of propagation up to distances

of 230 km. The statistical distribution of quasi peak field strength as a function of the time was determined for propagation over two paths of respective

lengths 110 and 270 km, at 90 mc, and over one of length 160 km at 45 mc, for a period of two years. The observed field strengths often considerably exceeded

the refraction. Some degree of correlation was found with meteorological data

obtained from routine radiosonde ascents. Use of the results in planning vhf

broadcasting services is outlined. --Authors' abstract.

E-150 Schachenmeier, Richard, Untersuchungen uber den Einfluss der Troposphare

auf die Ausbreitunq ultrakurzer Wellen. (Investigations of the influence of

troposphere on propagation of ultrashort waves. ) Archiv der Elektrischen Ubertragung, 5(l):l-9, Jan. 1951. 9 figs. , 8 refs. , 46 eqs. DLC -A method for

reliable calculation of field strength is demonstrated. The method is based on

the physical principles of propagation: (1) the combined effects of atmospheric

refraction, and (2) diffraction due to the curvature of the earth. Values from

meteorological observations are compared and found in satisfactory agreement

with measured field strength at meter and decimeter wavelengths for different

land and sea paths. Propagation within and beyond the optical range is treated

separately. (Met. Abs. 8I-126)-W. N.
35

1952

E-151 Abild, Bruno; Wensien, H. ; Arnold, E. and Schikorski, W. (Aerologische

Station, Flensburg, N.W.Germany), Uber die Ausbreitung ultrakurzer Wellen

ienseits des Horizontes unter besonderer Berucksichtigung der meteorologischen

Einwirkungen. (Propagation of ultrashort waves beyond the horizon with special

consideration of meteorological influences.) Hamburg. Nordwestdeutscher

Rundfunk, Technische Hausmitteilungen, 4(5/6 ):85-100, May/June 1952. 25

figs. , 7 tables, 7 refs. , 43 eqs. Abstracted from reprint. DWB--After a detailed theoretical analysis of ultrashort wave propagation, in which the effect

of various conditions in the deflection and the interference zones is investigated and illustrated by numerous diagrams, tables and graphs, the authors

report field intensity measurements conducted in N. W. Germany. General con- clusions are deduced from observed high field intensities and corresponding

synoptic situations. Data on the correlation between field intensities and

height and thickness of inversions, pressure and temperature are presented.

Seasonal variations of inversions, of anomalous field intensities, etc. , are shown in tables and graphs. The authors conclude that both ground level

inversions and those above 3000 m increase field intensities. A few situations

in which the effect of inversions was particularly noticeable are described.

(Met. Abs. 8I-130)-G.T.

E-152 Abild, Bruno, Uberreichweiten bei ultrakurzen Wellen und ihre meteorologischen Ursachen. (Extended ranges of ultrashort waves and their meteorological

causes.) Germany. Deutscher Wetterdienst in the US-Zone, Berichte, No. 35:

227-228, 1952. Also issued as Hamburg. Norwestdeutscher Rundfunk, Technische Hausmitteilungen, 4:4-11, 1952. 20 figs. , 10 refs. DWB--Experimental

transmissions of 3 m waves were carried out by the Nordwestdeutscher Rundfunk

(1951) over a 150 km overland path. The receiving site (200 m transmission

height) was about 100 km beyond the normal horizon. The field strength observations agreed well with the 6 hourly radiosonde and surface observations. The

cause of the extended range (beyond the horizon) is explained by heavy inversions, but the obvious close correlation between propagation and the meteorological factors as a function has not been explained. A statistical evaluation

might be possible, hence charts based on meteorological observations will be

made in an attempt to forecast time of the day and the month when the phenomenon might occur. (Met. Abs. 8I-129)--W. N.

E-153 Anderson, L.J. (Res. Div. U.S. Navy Electronics Lab. ), Calculator for atmospheric refractive index. U. S. Navy Electronics Laboratory, Report, 279,

March 18, 1952. 7 p. 4 figs. (fold.). DWB--The calculator, developed at NEL, provides a simple and accurate method of obtaining true and modified

refractive index values from temperature, humidity, and altitude data. Its principal advantage over other refractive index calculators is that only one

setting is required per value. Base diagrams are provided for humidity ex- pressed as either dewpoint or wet bulb temperature. Rotor diagrams are supplied for calculation of either true or modified refractive index. (Met. Abs.

4. 9-247) --Author's abstract.
36

E-154 Beckmann, B. , Die ionospharische und tropospharische Steuerung der Funkwellenausbreitung. (Ionospheric and tropospheric steering of wireless broadcasts.) Zeitschrift fur Meteorologie, 6(4): 112-117, April 1952. 4 figs. , 10

refs. , 8 eqs. MH-BH--The transmitting frequency (UFB) of the space wave

from a broadcasting station lies between the limits of reflection and damping

in the ionosphere. Its distribution, diurnal and annual variations are illustrated and discussed. Refraction in the troposphere (normally at about 8000

m) plays an important part in extending the range only of ultrashort and decimeter waves in inversions. It is much less regular than ionospheric steering.

The index of refraction, which depends on moisture content, is small and

only becomes effective with wave inclination under 1°. (Met. Abs. 3.9-235)

-C.E.P.B.

E-155 Brocks, Karl, Die Lichtstrahlkrummung in den unteren 500 m der Atmosphare . (Tabellen des Refraktions-koeffizienten, II. Fur Hohenmessunq und Radiometeorologie) . (The curvature of light rays near the earth's surface. (Tables

of the refraction coefficient, Pt. 2, For height measurements and radiometeorology).) Annalen der Meteorologie, 5(l-2):47-57, 1952. 3 figs. , 7 tables,

16 refs. German and English summaries p. 47. DWB--This part of a two part

article gives bi-hourly mean values of refraction in central and west Europe

from 0. 5-500 m above level plains. These are calculated from mean temperatures ignoring humidity, but the effect of humidity is discussed. Subsidiary

tables for June and December give values for clear and overcast days and

effect of sun's altitude. Special cases are discussed. A formula is given

for refraction of ultrashort radio waves in terms of pressure, temperature and

vapor pressure. Pt. 1 deals mainly with optical rays (Met. Abs. 2. 1-178).

(Met. Abs. 4. 5-221) -C.E.P.B.

E-156 Christall, F.I. and Cubitt, J. D. , Unusual radar performance. Red Sea.

Marine Observer, 22(55): 14-15, Jan. 1952. DWB--March 1, 1951. Pronounced

echoes at 50, 000-60, 000 yards separated by a gap from normal echoes at 30, 000 yards. Example of superrefraction. (Met. Abs. 3.9-236).

E-157 Cornell Univ. School of Electrical Engineering, Investigation of air-to-air and

air-to-ground electromagnetic propagation. Contract AF 33(038) -1091, Interim

Engineering Report, No. 15, June 10, 1952. 23 p. 2 figs. , 2 tables, eqs.

DWB-- Various forms of the correlation functions were discussed, the importance of which were demonstrated by deriving their corresponding scattering

coefficients. The theoretical results showed that if the average signal power

and noise power are constant, the correlation functions are related by a constant factor. The small value of the signal to noise ratio must be attributed

to "noise". Some results of variation of scale intensity with height were

given. (Met. Abs. 8I-134)»W. N.

E-158 Crain, CM. and Deam, A. P. , An airborne microwave refractometer. Review

of Scientific Instruments, N. Y. , 23(4): 149-151, April 1952. 2 figs. , 4 refs.

DLC--A device for measuring directly tropospheric index of refraction fluctuations and profiles is described. The change in resonant frequency of a cavity

resonator exposed to atmospheric air is recorded continuously, thus giving a continuous recording of atmospheric index of refraction relative to an arbitrary

reference. The method used for sampling the air and the measured errors involved are described. A typical segment of recorded data is shown. --Authors'

abstract.
37

E-159 Crain, CM. and Gerhardt, J. R. , Measurements of the parameters involved in

the theory of radio scattering; in the troposphere. Institute of Radio Engineers,

N. Y. , Proceedings, 40(l):50-54, Jan. 1952. 5 figs. , table, 6 refs. , 2 eqs.

DLC --Preliminary measures of the scale and the intensity of turbulence were

obtained by direct measurements of the variation of the index of refraction and

the associated temperature fluctuations from 10 in. to 50 ft above the ground.

The observations have been carried out by the Electrical Engineering Research

Laboratory of the University of Texas since 1948-49. It is shown that the in- stantaneous patterns of temperature, moisture or refractive index generally

have a magnitude significantly greater than zero. Observations to 300 ft above

the ground will be made. (Met. Abs. 8I-135)--W. N.

E-160 Crawford, A. B. and Jakes, W.C.Jr. , Selective fading of microwaves. Bell

System Technical Journal, 31(l):68-90, Jan. 1952. 14 figs. , table, 4 refs.

DLC --The results of an extended survey of microwave propagation over two lineof-sight paths in New Jersey are described. Angle-of-arrival measurements at

1. 25 cm wavelength and selective fading observations in a 450 Mc frequency

band centered at 2950 Mc show that the severe fading can be explained in terms

of multiple path transmission. A computer of the analogue type was built to stimulate the more complicated selective fading patterns. (Met. Abs. 81-136)

--Authors' abstract.

E-161 Dolukhanov, M.P. , Rasprostranenie radiovoln. (Radiowave propagation.

Moscow, Gosud. Izdatvo Literatury po Voprosam Sviazi i Radio, 1952. 490 p. Refs., numerous figs. , tables, eqs. DLC (QC661. D6)--A textbook on radio

propagation, going quite extensively into surface propagation, ionospheric pro- pagation, long wave, short wave, and ultrashort wave propagation and, finally,

atmospherics and cosmic noise. Tropospheric meteorological factors are discussed on p. 436-461, in the chapter on ultrashort wave propagation. Theory,

curves, etc. , are given for humidity and temperature effects, channels and

turbulent dispersion, absorption and beyond-the-horizon propagation. (Met.

Abs. 10.9-12)-M.R.

E-162 Fine, H. , Variation of field intensities over irregular terrain within line of

sight of the UHF band. Institute of Radio Engineers, N. Y. , Transactions,

No. PGAP-4:53-65, Dec. 1952. 11 figs. , table, 3 refs. DLC --Statistical

analysis of available data from field strength surveys enabled empirical propagation formulas to be deduced for the whole UHF television band from 300

to 900 Mc to assist the Federal Communications Commission in the problem

of frequency allocation for UHF television broadcasting stations.

E-163 Fukushima, M. ; Tao, K. ; Uyesugi, Y. et al. , Ultrashort wave propagation

and mirage. Journal of Geomagnetism and Geoelectricity, Tokyo, 4(3/4): 141-

146, Dec. 1952. 6 figs. , table, 4 refs. DLC --Observations of field intensity

at 472, 153 and 60 Mc and of vertical distribution of meteorological elements

in the lower atmosphere were carried out to make clearer the anomalous propagation of VHF and UHF waves at the coast of Toyama Bay during a month in

which mirages appeared. On the days when mirage appeared, the field intensities of shorter waves increased considerably, especially at 472 Mc. Radio

ducts were observed on these days and they were so intense as to transmit the

472 Mc wave. From this consideration, the mirage and the radio duct are thought to be due to the same meteorological conditions. The results of this

study are applicable to forecasting the anomalous propagation of ultrashort

wave in the neighborhood of the coastline. --Authors' abstract.
38

E-164 Gast, E. ; Essen, L. and Froome, K. D. , The refractive indices and dielectric

constants of air and its principal constituents at 24, 000 Mc/s. Archiv der

Elektrischen tfbertragung, 6(12):532-534, Dec. 1952. Fig. , 2 tables. DLC--

The oscillator, the accuracy of which is comparative to that of the optical range,

is briefly described and outlined in a diagram. Results of measurements of air,

nitrogen, oxygen and argon free from carbon dioxide are presented in tables,

featuring a number of results at various frequencies by other workers. For the

refractive index of humid air under different atmospheric conditions formulas were deduced that can be reduced to normal atmospheric conditions by:

(nt.P - D.106 = i^ . pi+

IZLA. . p2+ 8|26 p3(1+ 52^48

}>

where P, , P« and P„ stand for the part pressure of dry air, carbon dioxide and

water vapor; t = the temperature in C; T = t + 273 the absolute temperature.

The value for the dipole moment of the water vapor molecule was deduced as 1.839 + 0.002- 1018

. (Met. Abs. 8I-137)--W. N.

E-165 Grant, Arthur S. G. (Met. Serv. , Canada), Some meteorological problems of

electronic surveying. Royal Meteorological Society, Canadian Branch, (Publications), 3(3), 1952. 9 p. Fig., 9 refs. DWB--The technique of electronic

surveying is described. Distances are measured by radar from aircraft with a known elevation and values obtained are then reduced to map distances. The

author briefly discusses the effect of atmospheric conditions on the determination of aircraft elevation, and on the atmospheric refraction of radio signals.

(Met. Abs. 4. ll-37)-G.T.

E-166 Hay, H. G. and Unwin, R.S., Tropospheric wave propagation in a duct of non- uniform height. Physical Society of London, Proceedings, Ser. B, 65(12):981-

989, Dec. 1, 1952. 3 figs. , 4 refs. , 26 eqs. DWB--The simple mode theory of

tropospheric refraction (H.G.BOOKER and W. WALKINSHAW, 1947) is extended

to cover situations where refractive index profile varies, e.g. , with distance

offshore. The expression for field strength in decibel form is applied to experimental data on radio ducts off New Zealand, duct width increasing from 100 ft near coast to 350 ft at 55 km, and gave values of field strength of the right

order at long ranges. A more general expression for field strength is also given.

(Met. Abs. 4. 5-238)-C.E.P.B.

E-167 Hirao, Kunio; Uyesugi, Y. and Tao, K. , Propagation characteristics of VHF

over a distance of 125 km. Journal of Geomagnetism and Geoelectricity, Tokyo,

4(3/4): 131-140, Dec. 1952. 15 figs. , 4 tables, 7 refs. DLC -A statistical

study of the field intensity of VHF wave over a distance of 125 km was made

by using mainly the observed data of 150 Mc and partly those of 65 Mc. For

this purpose, the weather maps, the aerological data obtained at Tateno Aerological Observatory and the meteorological elements observed at Kokubunji and

Hiraiso were fully investigated. The field intensity and the range of its diurnal

variation are large in summer and spring, and small in winter and on days with

precipitation. Abnormally high field intensity which appears frequently, and

its severe variation, are considered to be caused by the complicated distribution of meteorological elements in the lower atmosphere. The effect of front

is recognized and it seems to be more remarkable at night than in daytime.

--Authors' abstract.
39

E-168 Hund, August, Short wave radiation phenomena. N. Y. , McGraw-Hill, 1952.

2 vol. 1382 p. 394 figs. , 97 tables, 1009 eqs. , bibliog. p. 1288-1301. DLC

(QC661.H83)--This valuable work covers theoretical and experimental contributions from the discovery of electromagnetic waves to their applications in radio

communication and in guided missiles. The nine chapters are as follows: Ch. 1,

Fundamental concepts and relations of currents and electromagnetic fields; 2,

Space electromagnetic fields of elementary electric and magnetic dipoles; 3,

Fundamental methods used in electromagnetic theory; 4, Propagation characteristics; 5, Transmission lines and radiation; 6, Unobstructed space radiation;

7, Space radiation in the presence of electromagnetic obstruction; 8, Electromagnetic diffraction, and 9, Wave guides and cavities. Cross references are provided. The last three chapters deal particularly with radiometeorology. The

appendix provides a list of the symbols used and an extensive bibliography.

Met. Abs. 8 1-139) -W.N.

E-169 Institute of Radio Engineers --International Scientific Radio Union, Wash. ,D.C,

April 21-24, 1952. Proceedings. Institute of Radio Engineers, N. Y. , Proceedings, 40(6): 738-748, June 1952. --Contains the summaries of 71 technical papers

presented at meeting, including 6 on tropospheric propagation (papers 5 and

20-25). --E. K.

E-170 Kirby, Robert S. ; Herbstreit, J. W. and Norton, K.A. , Service range for air- to-ground and air-to-air communication above 50 Mc/s . Institute of Radio Engineers, N. Y. , Proceedings, 40(5): 525-536, May 1952. 17 figs. , 3 tables, 10

refs. , 10 eqs. DLC --Propagation aspects of air-to-ground and air-to-air communications are analyzed. Contours of constant received signal strength are shown in the form of lobes for various frequencies. It is shown that for systems with equivalent transmitted power, ground antenna height, and transmitting and receiving antenna gain the service range decreases as the frequency is

increased. This is due primarily to a decrease in the absorbing area of the re- ceiving antenna and to a larger number of nulls in the lobe structure arising

from interference between direct and ground reflected waves. Ground station

antenna height diversity and tilted array ground antenna systems are discussed

as a means of improving coverage as the operating frequency is increased.

--Authors' abstract.

E-171 LaGrone, Alfred H. , Volume integration of scattered radio waves. Institute

of Radio Engineers, N. Y. , Proceedings, 40(1):54, Jan. 1952. Fig., 3 refs. , eq. --The general equation for radio scattering developed by Booker and Gordon

is extended to a volume integral equation, which gives the total scattered

power density per unit cped at a receiver point relative to the power radiated

per unit solid angle by an isotropic source. --Author's abstract.

E-172 Lauter, Ernst A. and Bartels, G. (Met. Obs. , Kuhlungsborn, Germany), Optische

Refraktion and Ultrakurzwellenausbreitung im Ostseeraum im Fruhjahr 1952.

(Optical refraction and propagation of ultrashort waves in the Baltic Sea area

spring 1952.) Zeitschrift fur Meteorologie, 6(7):215-220, July 1952. 7 figs. , 2 refs. DWB--Unusually strong refraction phenomena observed at the Met. Obs.

Kuhlungsborn, N. Germany, March 14, April 17 and May 2, 1952, are described

in detail and compared with the synoptic situation and with ultrashort wave propagation investigated at the same time. It was found that variations in optical

refraction index are not always in a direct relationship to variations in ultrashort wave reception field intensity. The considerable effect of horizontal at- mospheric heterogeneity on the propagation of ultrashort waves is stressed.

(Met. Abs. 4. 9-250) --G.T.
40

E-173 Neumann, J. , Diurnal variation of the subsidence inversion and associated

radio wave propagation phenomena over the coastal area of Israel . Israel.

Meteorological Service, Ser. A, Meteorological Notes, No. 6, 1952. 16 p. 5 figs. , table, 10 refs. , 20 eqs. MH-BH--Mean height, pressure, temperature

and humidity of base and top subsidence inversion at Lydda Airport at 1, 7, 13

and 19 h were found for July 1945 and diurnal variations computed. Inversion

base-top varied from 678-1101 m at 7 h to 486-781 m at 19 h and is probably lowest at 17 h. Main rises (1-7 h) and falls (13-17 h) are associated with conver- gent land and divergent sea breezes. The modified refractive index profiles for radio waves are calculated; the lowest level of the elevated duct and greatest

hydrolapse account for the observed optimum propagation in the evening.

(Met. Abs. 8I-14D-C.E.P.B.

E-174 Northover, F.H. , The anomalous propagation of radio waves in the l-10m band.

Journal of Atmospheric and Terrestrial Physics, 2(2):106-129, 1952. Fig., 12

refs. , 109 eqs. DWB--Anomalous propagation of meter waves is discussed

mathematically and results applied to an observed dry bulb inversion from 41-

51°F at 3900 ft above Cardington, England. Wet bulb 40°F. It is found that

such an upper inversion, sharp enough to act as a discontinuity, can cause

considerable anomalous propagation in waves of 3-1/2 and 7 m. (Met. Abs.

3.9-237)--C.E.P.B.

E-175 Schulkin, M. , Average radio-ray refraction in the lower atmosphere. Institute

of Radio Engineers, N. Y. , Proceedings, 40(5): 554-561, May 1952. 7 figs. , 2 tables. DLC --Presents empirical results (accompanied by many useful curves)

of computations for a range of climatological conditions in North America, of

the bending of rays that pass entirely through the atmosphere and arrive or depart tangentially to the earth's surface. Ninety percent of the ray bending

occurs in the lowest 10 km of the atmosphere. The results are compared with

the standard refraction approximation and it is found that although in the aver- age case there is fairly good agreement, the deviation from the true refraction

is large, both as a function of altitude and of geographical location. Most of

the curves are based on data for Washington, D.C. (Met. Abs. 4.7-231)

»W. N.

E-176 Spencer, C. W. , Radiowave propagation at 89 Mc/s in rt/ation to synoptic

conditions . Meteorological Magazine, London, 81(961) : 206-212, July 1952.

Fig. , 4 tables, 5 refs. DWB--Superrefraction of 3. 4 m waves over a distance

of 257 km was recorded daily at Slough, Eng. It was compared with isobaric

curvature; greatest relative frequency with cols, easterly and southerly types,

least with cyclonic and northerly types. Nearly always with elevated (below

700 mb) or less often surface inversions, especially 950-900 mb. (Met. Abs.

8I-145)»C.E.P.B.

E-177 U.S. Air Force, Third Air Weather Group, Ent Air Force Base, Colorado Springs,

Computing the index of refraction of the atmosphere . Its Technical Paper, No. 1,

May 1952. 14 p. 5 figs. , 6 refs. DWB--In this practical guide, the equation

for refractive index is stated and orders of magnitude of temperature and moisture gradients which result in nonstandard radar propagation are given. Superrefraction may be due to a strong temperature inversion (about 3°C/100 ft), a strong lapse in moisture (1/2 gm/kg/100 ft), or a combination of these factors.

(Met. Abs. 8I-146)--R.S.Quiroz.
41

Vassy, Arlette and Vassy, Etienne, Interpretation d'un type particular d'echo

de radar. (Interpretation of a special type of radar echo. ) Academie des

Sciences, Paris, Comptes Rendus, 235(20): 1240-1242, Nov. 17, 1952. 2 refs.

DWB--The peculiar radar echo from a cloudless sky (first observed by J.BROCH

on a 3. 2 cm radar over the ocean) was again observed in the summer of 1952.

This paper is an attempt to interpret the phenomenon as a coincidence of meteorological factors favoring superrefraction. (Met. Abs. 8 1-147) --W. N.

Wickizer, G.S.and Braaten, A.M., Field strengths recorded on adjacent FM

channels at 93 Mc over distances from 40 to 150 miles. Institute of Radio

Engineers, N. Y. , Proceedings, 40(12): 1694-1699, Dec. 1952. 14 figs. , table,

ref. DLC-Field strengths of KE2Xcc (93. 1 Mc, Alpine, N.J.) and WBZ-FM

(92.9 Mc, Boston, Mass.) have been recorded for more than a year at two locations (Hauppauge and Riverhead) on Long Island. Statistical analysis of data

for the evening hours reveals a broad seasonal trend toward higher intensities

in the summer, with larger over-all variation on the longer transmission paths.

Based on analysis of one summer month, refraction effects appeared to vary

independently in two directions. During periods of rapid and violent fading,

hourly median field strengths of WBZ-FM varied over a range of 32 db at Riverhead and 25 db at Hauppage. Furthermore, for the above mentioned fading conditions, it was observed that on the 150 mi path, the hourly curves of field

strength distribution with time approached a log normal distribution when the

median field was less than 10 db above 1/U-v per meter, and a Rayleigh distribution when the median field was greater than 15 db above l^t-v per meter.

(Met. Abs. 8 1 -148) -Authors' abstract.

1953

Aden, Arthur L. , Feasibility of detecting atmospheric inversions by electromagnetic probing. U.S. Air Force. Cambridge Research Center, Air Force

Surveys in Geophysics, No. 34, March 1953. 9 p. 7 refs. , 19 eqs. DWB--

An outline is given of the theory of standard and nonstandard propagation

characteristics of electromagnetic waves, dependent on discontinuity of the

refractive index. Vertical incidence atmospheric probing with standard L-band

radar equipment should not give reflections from temperature and humidity inversions. There is only a remote possibility that proper equipment could be

developed. (Met. Abs. 8J-2)-A.A.

Al'pert, Ia.L.; Ginzburg, V.L.and Feinberg, E.L., Rasprostranenie radiovoln. (Radiowave propagation.) Moscow, Gos. Izdat.Tekhniko-Teoreticheskoi Literatury, 1953. 883 p. 128 figs. , 124 tables, 373 refs. DLC. Translations of

several chapters into English available Special Libraries Association, Translation Center (John Crerar Library, Chicago) as its R-1929 to R-1937. --The most

advanced text on theoretical and empirical aspects of radio wave propagation

in all bands from microwaves to long waves, and in the troposphere and ionosphere. First, there is a historical sketch of progress in radio science since

POPOV (1845), especially in Russia. Then in Pt.I, the general theory of radio

propagation; Pt.II, theory of propagation in ionosphere (p. 278-546); Pt. Ill, structure of ionosphere and experimental data on formation; regular and irregular processes in ionosphere (p. 547-680); Pt.IV, experimental investigations on

propagation and comparison with calculated data by various methods (p. 681-

870). The first part of this voluminous text is mainly theory; the last part is
42

practical data, tables, recorder records and interpretations, nomograms, etc. All of the layers of the ionosphere are treated, as well as the troposphere, in

relation to long distance propagation. Radar and impulse propagation are also

considered. The extensive bibliography in 5 parts consist of about half Russian and half foreign literature through 1952. (Met. Abs. 8J-3)--M. R.

E-182 Ament, W. S. , Toward a theory of reflection by a rough surface. Institute of

Radio Engineers, N. Y. , Proceedings, 41(1): 142-146, Jan. 1953. Fig., 3 refs.,

19 eqs. --A rough, perfectly reflecting surface is first specified by the statistics of noise theory. If illuminated by a plane electromagnetic wave, such a surface would reflect statistically predictable fields. An attempt is made to formulate the problem of predicting the fields in terms of the statistics of the

surface with particular applicability to predicting theoretically the effect of

oceanic swell and chop on the propagation of microwaves. The result is a series of integral expressions in which averages of the currents induced in the

surface appear as unknown functions. Owing to mathematical complexities,

these expressions are not solved for the average currents; however, a qualitative discussion is given of a known formula for the specular reflection coefficient of a gently rolling surface. --Author's abstract.

E-183 Anderson, L.J. and Gossard, E. E. , The effect of the oceanic duct on microwave propagation . American Geophysical Union, Transactions, 34(5): 695- 700,

Oct. 1953. 7 figs. , 8 refs. , 3 eqs. DLC--A body of experimental radio and

meteorological data taken over Cardigan Bay, on the British west coast, is

examined to ascertain how radar propagation is affected by the microwave duct

lying next to the sea surface. The boundary layer meteorological profiles are analyzed in terms of semi-empirical relation due to E.L. DEACON, and propagation is predicted according to a method of S. A. SCHELKUNOFF. At 3 cm wavelengths, it is found that the agreement between observation and theory becomes

steadily better as wind speed increases, until at speeds above 15 mi/hr (7m/s)

the consistency is truly striking. At lower wind speeds there is a definite ten- dency to follow the theoretical pattern, but a great deal of scatter is noted.

Possible explanations for this scatter are offered. More scatter is observed at 9 cm than at 3 cm, and the transition to trapping conditions is less definite.

The 9 cm waves appear to "feel" the effects of the duct some time before trapping occurs. An interpretation is offered of the fact noted by MCPETRIE and

STARNECKI that, in general, high signals are associated with large positive

air-sea temperature differences, while low signals are accompanied by large

negative differences. Also, Jones' observation that under unstable conditions

high winds are accompanied by high signals is nicely explained. (Met. Abs.

8 J-5) --Authors' abstract.

E-184 Anderson, L.J. and Gossard, E.E. , Oceanic duct and its effect on microwave

propagation. Nature, London, 172(4372): 298-300, Aug. 15, 1953. 4 figs. , 4 refs. , eqs. DWB--A criterion for trapping in a surface duct is derived in

terms of index of refraction at level at which meteorological observations are taken and at sea surface, profile index of potential refractive index, and sur- face roughness. This is checked against field strength observations over Cardigan Bay with fairly good results. (Met. Abs. 5. 6-283)--C. E. P. B.
43

E-185 Anderson, L.J. and Gossard, E. E. , Prediction of the nocturnal duct and its

effect on UHF. Institute of Radio Engineers, N. Y. , Proceedings, 41(1): 135-139,

Jan. 1953. 6 figs. , 4 refs. , 7 eqs. DLC--A method is described for predicting

diurnal variation in UHF field strengths, which is based on the micrometeorology

governing the nighttime refractive index profiles. Using surface meteorological

data from past years, predictions are made of the probability distribution of the

diurnal field variations to be expected on 100 and 1000 Mc over CRPL links in

Colorado. The predictions are compared with field strength observations taken

in 1952, and the agreement is encouraging. (Met. Abs. 8 J-4) --Authors' abstract.

E-186 Bean, Bradford R. , The geographical and height distribution of the gradient of

refractive index. Institute of Radio Engineers, N. Y. , Proceedings, 41(4):549-

550, April 1953. 3 charts, 4 refs. , eq. DLC. Also issued as U.S. National

Bureau of Standards, NBS Report, No. 1720. --Very brief text accompanying two

charts featuring the Feb. and Aug. distribution of the effective earth's radius

factor over the U.S. Another chart shows the distribution of refractive index

for warm, temperate and cold climates. (Met. Abs. 8J-6)--W. N.

E-187 Bellaire, F. R.and Arvola, W. A. (both, U. S. Navy Electronics Lab. , San Diego),

Prediction of diurnal field strength patterns by synoptic methods . (In: Conference

on Radio Meteorology, Univ. of Texas, Austin, Nov. 9-12, 1953, Proceedings,

Vol. (l):III-4, pub. 1953. 7 p. 4 figs.) DLC, DWB»Best VHF-UHF propagation

to a point beyond the horizon occurs when a shallow layer of moist air lies under

a dry layer and the worst conditions occur when air is dry or moist (unstable) to great heights. Southerly flow from Gulf of Mexico, weak pressure gradient, clear

skies, varring winds, laminar structure (from Raob data), large diurnal temperature range, fog at night, and light winds give highest signals. Seven flow or air

mass classes were designated for correlation with signal strength. Large diurnal

variations in signal strength is characteristic of high intensity signals (at night)

and low variations with low intensity. Air mass changes are apt to produce

greatest deviations of actual from predicted values of diurnal curve. (Met. Abs.

8J-7)-M.R.

E-188 Bremmer, H. , The troposphere as a medium for the propagation of radio waves

-I. II. Philips Technical Review, Eindhoven, Netherlands, 15(5, 6): 148-159;

175-181, Nov. , Dec. 1953. 10 figs. , 24 refs. , eqs. DLC -For microwave (•=

10 m) propagation the troposphere below 10 km (or the refraction index in the tro- posphere), not the ionosphere, has proven to be the most critical region of the

atmosphere. Knowledge of this troposphere propagation and of the physical characteristics of the troposphere which affect microwaves is reviewed. Six methods

by which microwaves are transmitted are examined: a) along 2 normal paths, one

direct and one reflected; b) along a few rays via a transition layer; c) superrefraction (along many rays as in a wave guide with the troposphere as the wave

guide; d) via reflection due to (temperature and humidity) gradient changes;

e) by diffraction and f) by scattering. The last named method is discussed in

great detail as it is responsible for interference from distant transmitter and

hence, is the most important factor in assigning wave lengths and spacing of

transmitters in order to avoid interference. (Met. Abs. 6. 6-156)--M. R.
44

E-189 Browne, Ian C. , Radar echoes at vertical incidence from a horizontally stratified

atmosphere. Royal Meteorological Society, Quarterly Journal, 79(339): 157-160,

Jan. 1953. 2 figs. , 8 refs. , 4 eqs. DWB--On July 12, 1949, on 3.2 cm radar at Cambridge, Eng. , an echo (angel) was received from a horizontal layer 300 ft thick at 4560 ft, attributed to a humidity discontinuity of 40% at an anticyclonic

inversion. (Met. Abs. 8 J-9)--C. E. P. B.

E-190 Bullington, Kenneth, Radio transmission beyond the horizon in the 40 to 4000

Mc band. Institute of Radio Engineers, N. Y. , Proceedings, 41(1): 146-152,

Jan. 1953. Fig. , 16 refs. , 21 eqs. DLC --After defining and calculating the

transmission loss, author discusses the subject as related to ionospheric and

tropospheric propagation, involving Rayleigh's theory. Latter part of the paper

is devoted to the maximum range of a radio system along with noise problems

caused by other radios. (Met. Abs. 8 J-10)--W. N.

E-191 Byam, L.A. and Miller, J. Z. , Notes on propagation. Institute of Radio Engineers, N. Y. , IRE Convention Record, Pt. 2. Antennas and Communications,

p. 68-76, 1953. 11 figs. , 5 refs. DLC--A brief discussion of the fading which

occurred during an extended microwave propagation experiment, operated at a frequency of 4000 Mc. Attention was directed primarily to those fades which

dropped 15 db or more from the normal signal level. For each such fade, the

essential data were extracted and tabulated, including information with respect

to the corresponding level of the diversity (or main) signal. --E. K.

E-192 Clemmow, P.C., Radio propagation over a flat earth across a boundary separating two different media . Royal Society of London, Philosophical Transactions,

Ser. A, 246:1-55, 1953. 16 figs. , 252 eqs. , bibliog. p. 54-55. DLC -A theoretical investigation is given of the phenomena arising when vertically polarized

radio waves are propagated across a boundary between two homogeneous sections of the Earth's surface which have different complex permittivities. Then

an analytical treatment is given of a suitable simplified problem which is fundamental in the theory of radio propagation over an inhomogeneous Earth. This

purpose is achieved by establishing formulas from which any example could be

largely worked out. Finally, some ramifications of the theory are outlined.

-E.K.

E-193 Conference on Radio Meteorology, Univ. of Texas, Austin, Nov. 9-12, 1953,

Proceedings, (v. 1). Conference sponsored by The American Meteorological

Society, The Institute of Radio Engineers; The Radar Weather Conference;

The International Scientific Radio Union; The Joint Commission on Radio Meteorology of the International Scientific Unions. Austin, Bureau of Engineering

Research, Univ. of Texas, 1953. Each section repaged. Supplement (i. e. Vol.

2), pub. 1954. Also: Saxton, J. A. , Radiometeorology: Conference in Texas.

Nature, London, 173(4408): 761 -764, April 24, 1954. DWB»In Vol. 1, short

versions or summaries of 61 papers on Tropospheric propagation; Refractive

index; Atmospheric scattering and turbulence; Thunderstorm and tornado at- mospherics; Cloud and precipitation physics and Use of weather radar, as presented at the sessions on those topics during the Conference on Radio Meteorology Nov. 9-12, 1953 at Austin, Tex. The remaining papers and supplementary material, discussions, etc. , comprise the Supplement (i.e. Vol. 2)

which contains 17 papers on the various aspects of Radio propagation, Radar

meteorology, Turbulence, Cloud and thunderstorm physics and 11 pages of discussion on the various subjects covered in the conference, corrections on papers
45

in Vol. I, and a list of names and addresses of the participants. The article by

Saxton is an account of the Conference which mentions the papers and discussions. (Met. Abs.8J-ll; 6.5-352)--

Cowan, Leslie W. , Forecasting; refractive index profiles in the atmosphere.

U.S. Air Force. 3rd Weather Group, Ent Air Force Base, Colorado Springs,

Technical Paper, No. 2, Sept. 1953. 80 p. 51 figs. , 7 tables, 15 refs. , 2 eqs.

DWB--Meteorological factors affecting radar propagation in the troposphere are analyzed and methods of forecasting refractive indexes or superrefraction (or

the opposite) conditions set forth. Seasonal air mass and regional variations

in nonstandard conditions are treated in detail with profiles, tables, schematic

diagrams, nomograms, etc. Limitations of radiosonde observations and effects

of radiation or of sea or lake surface in modifying conditions are emphasized.

Radio climatological (inversion frequency) data for cities in the U.S. and for the

W.Atlantic are included on charts and frequency diagrams. (Met. Abs. 8J-12)

--M.R.

Cowan, Leslie W. , Interpreting refractive index profiles in terms of radar cover- age . U. S. Air Force. 3rd Weather Group, Ent Air Force Base, Colorado Springs,

Technical Paper, No. 3, Oct. 1953. 99 p. 13 figs. , 61 cases, table, 6 refs.

DWB--A manual giving information and nomograms necessary for calculating re- fractive index profiles, radio holes and other radar parameters involved in tropospheric propagation with transmitters 2000 ft, 1000 ft above and at base of layer,

or 500 ft or 1000 ft below layer or in surface duct, and for different thicknesses

of layer (50 ft to 1000 ft). Special cases of a radar on a coastal peak 3000 ft above the sea, and with targets 10,000 ft and 20,000 ft above transmitter, are considered. (Met. Abs. 8J-13)--M.R.

Crain, Cullen M. ; Deam, A. P. and Gerhardt, J. R. , Measurement of tropospheric index-of-refraction fluctuations and profiles . Institute of Radio Engineers,

N.Y. , Proceedings, 41(2):284-290, Feb. 1953. 8 figs. DLC --Simultaneous

records of index-of-refraction and of temperature fluctuations over the sea and

over coastal areas near Lakehurst, N.J. , are presented. They were obtained in

April 1951 by means of a microwave refractometer and a bead-type thermistor

carried by a Navy Type M airship up to 5000 ft. Index of refraction fluctuations

appear to be primarily due to fluctuations in air moisture content. Records showing refractive index profiles and fluctuations are also presented for Dayton, Ohio.

These were obtained in June 1951 with a refractometer carried up to 11,000 ft in a Type C-46 aircraft. Some details of the meteorological conditions prevailing

during the flights are mentioned, like the fact that whenever rough air was en- countered, the index of refraction showed rapid variations of large amplitude,

the reverse not being necessarily the case. In general, tropospheric index of

refraction fluctuations are found to vary greatly with time and space. (Met.

Abs. 4.8-266)--G.T.

Crain, Cullen M. , Refractometer measured tropospheric index-of-refraction

profiles, Vol. 1 . Texas. Univ. Electrical Engineering Research Laboratory,

Contracts AF 18(600)-113 and AF 19(604)-494, Report No. 6-02, Feb. 27,1953.

27 X 40 cm. 7 p. 10 + 42 + 31 graphs. DWB--Refractometer sounding curves

are shown on large sheets of graph paper for airplane soundings made in 1952

to 12, 000 ft altitude over SW Ohio, off the West Coast of Washington State and

west from San Francisco over the Pacific. The peculiarities of the curves are explained in terms of surface stratus layers in marine air off the West Coast,
46

upper layers of super refractive or sub-refractive air or steep gradients caused

by air mass discontinuities; either on individual days or as a general seasonal

condition. On the whole, conditions were more steady off the West Coast

(Aug. -Oct. ) than in Ohio (Aug. 1952). (Met. Abs. 5. 11-213) -M. R.

E-198 Crain, C. M. ; Straiton, A. W. and von Rosenberg, C.E. , A statistical survey

of atmospheric index-of-refraction variation. Institute of Radio Engineers,

Transactions, Vol. AP-1, No. 2:43-46, Oct. 1953. 8 figs. , 2 refs. , eqs.

DBS--This paper presents a statistical survey of index of refraction variations as recorded by an airborne microwave refractometer. Scales and intensities

of the index variations are given, as well as the parameters N^/l, for data

taken over southwest Ohio during summer months and over the Pacific Ocean

off the west coast of Washington in Aug. and of California in October. Heights

from 2000 and 12, 000 ft msl were considered with most of the data taken between 2000 and 12, 000 ft. Approximately, 1200 samples taken on 34 flights were analyzed. The composite of the data gave the following median values:

Index scale = 130 ft AN2 = 7X10-4 N 2/ft

Index intensity = 0. 3 N I (Met. Abs. 8 J- 15) --Authors' abstract.

E-199 Dickson, F.H. ; Egli, J. J. ; Herbstreit, J. W. and Wickizer, G.S., Large reduc - tions of VHF transmission loss and fading by the presence of a mountain obstacle

in bevond-line-of-sight paths . Institute of Radio Engineers, N. Y. , Proceedings,

41(8) :967-969, Aug. 1953. 2 figs. , 4 refs. DLC -Demonstrates how high mountain ridges can be utilized to reduce both transmission loss and tropospheric

fading. Experimental verification of principles involved is given here. (Met.

Abs. 8J-16J--W. N.

E-200 Doherty, L.H. , Effect of atmospheric ducts on line-of-siqht transmission.

U.S. Navy Electronics Laboratory, San Diego, Report, No. 409:51-55, 1953.

2 figs. DWB, DLC --It is shown that the ray theory may yield satisfactory answers to problems of tropospheric duct propagation. Some meteorological

conditions as mechanisms for specific propagation phenomena are discussed.

(Met. Abs. 8J-17)-W. N.

E-201 Epstein, Jess and Peterson, Donald W. , An experimental study of wave propagation at 850 Mc. Institute of Radio Engineers, N. Y. , Proceedings, 41(5):

595-611, May 1953. 34 figs. , 7 tables, 10 refs. , eqs. DLC»The prediction

of area coverage of a broadcast station is of prime importance. To do this re- quires evaluation of the effect of such factors as wave refraction, earth reflection, diffraction and attenuation. The following paper describes an experiment

conducted at 850 Mc which was undertaken to solve this problem. We have

concluded that useful predictions of wave propagation can be made with free

space theoretical field strength reduced by theoretical knife edge diffraction

shadow loss and by suitable empirical experience factors. (Met. Abe. 8 J- 18)

--Authors' abstract.
47

Fine, H. , Some notes on theory of radio scattering in a randomly inhomoqenous

atmosphere. Institute of Radio Engineers, N. Y. , Proceedings, 41(2):294, Feb.

1953. Eqs. DLC--A time-space correlation function is offered. Brief reference

to BOOKER and GORDON'S space correlation and STARAS' time correlation is

given. (Met. Abs. 8 J-176)--W. N.

Herbstreit, J. W. ; Norton, K. A. ; Rice, P.L.and Schafer, G. E. , Radio wave

scattering in tropospheric propagation. Institute of Radio Engineers, N. Y. , Convention Record, Pt. 2:85-93, 1953. 6 figs. , table, 10 refs. , 26 eqs. DLC

(TK6541.I5)--The scattering theory of BOOKER and GORDON has been developed,

assuming the correlation function C(r) = C(0)exp(-r/l), so as to be suitable for easy numerical calculation of the transmission loss expected with this mode of

transmission; C(O) denotes the variance with time of the refractive index of the

atmosphere and I denotes the scale of turbulence. In this development, the

parameter C(0)/1 emerges as a direct measure of the radio wave power trans- mitted by this mode of propagation. The theory is used to calculate the trans- mission loss to be expected on the transmission paths involved in the NBS

Cheyenne Mountain experiment which cover the transmitting antenna height range

from 30 to 7,800 ft, distance range 223 to 628 mi, and frequency range 100-1,046

Mc. The dependence of C(O)/! on height above the earth's surface which must

be assumed in these predictions to obtain agreement with the experimental trans- mission loss data is in qualitative agreement with the meager meteorological data

which are now available for estimating this parameter. (Met. Abs. 8J-19)

--Authors' abstract.

Hood, A. D. and Doherty, L.H. (both, Radio and Elec. Engr. Div. , Nat' 1. Res.

Council, Ottawa), Radar forecasting on Lake Ontario. (In: Conference on Radio

Meteorology, Univ. of Texas, Austin, Nov. 9-12, 1953, Proceedings. Vol.1:

III -6, pub. 1953. 7 p. 4 figs. (incl. photos), ref . ) DLC, DWB--Correlation with

duct height as predicted by the power law was compared with the duct height observed at 1830 or 1930 EST, and presented graphically for Aug. and Sept. 1952.

The results, excluding days of frontal passage and/or no surface ducts, indicate

a maximum value of duct height. No echoes were visible during standard propagation conditions. The diurnal variation is distinct during summer. The 3 cm

radar used scanned a 180° sector and gave a vertical view of every 8 ft to a height of 220 ft every 30 sec. (Met. Abs. 8 J-20)--W. N.

Institute of Radio Engineers. Committee on Wave Propagation, Tropospheric

propagation: a selected guide to the literature . Institute of Radio Engineers,

N.Y. , Proceedings, 41(5): 588-594, May 1953. Numerous refs. DWB--This

bibliography is mainly for the non-specialist seeking information on details of

tropospheric propagation. The subject arrangement of the contributions reviewed

is as follows: Books; general discussions; diffraction; refraction (rays, modes

and ducts, elevated layers, angle of arrival); lobe structure; time and space var- iations of field strength, attenuation by atmospheric gases and precipitation;

ground and sea roughness; meteorological echoes; velocity of propagation. The

review is based on American and British sources. (Met. Abs. 6B-152)--G.T.

Jehn, K.H. and Staley, R.C., Correlations of 100 Mc radio propagation with

certain meteorological variables . Journal of Atmospheric and Terrestrial Physics,

3(3): 163-171, April 1953. 9 figs. , 6 refs. DWB-Signal strengths of 100 Mc

(3 m) waves received at Austin, Texas, from San Antonio (78 mi) and Dallas
48

(175 mi), are compared with meteorological data. It is found that high signal

strength is associated with maritime tropical and low with polar continental air. Some relations were found with height of base of refracting layer but it is suggested that these were due to the presence of multiple refracting layers. A

time-height turbulence plot is shown for San Antonio up to 25, 000 ft and some

relation is found to signal propagation. (Met. Abs. 8 J-22)--C. E. P. B.

E-207 Johnson, Walter E. , Analogue computer for the solution of the radio refractive

index equation. U.S. National Bureau of Standards, Journal of Research, 51(6):

335-342, Dec. 1953. 7 figs. , table, 5 refs. DWB-The solution to the radio

refractive index equation provides information necessary to the research worker

studying tropospheric radio propagation in the very high and ultrahigh regions.

Present means of computation are either time consuming or of low accuracy. An

analogue computer is developed to solve this equation by utilizing basic computation circuits incorporated into a null balance bridge circuit. A unique fea- ture of this computer is the modification of a linear 10 turn potentiometer so

that its output to input voltage ratio versus rotation closely approximates the

exponential type curve of the saturated water vapor term in the refractive index

equation. This computer is now in use at the Central Radio Propagation Laboratory of the National Bureau of Standards, Boulder, Colo. , and has superseded

other methods of calculating the radio refractive index. (Met. Abs. 5. 8-96)

--Author's abstract.

E-208 Kiely, D. G. , Some measurements of fading at a wavelength of 8 mm over a very

short sea path. Baldock, Hertfordshire, Services Electronics Research Laboratory, S.E. R.L. Technical Journal, 3(1):15-18, March 1953. 2 figs. , table, 3

refs. Mimeo. GB-MO--A one-way link one mile long was set up across Loch

Goil, Scotland, transmitter 15 ft above MSL, receiver 100 ft, to investigate

superrefraction on 8 mm wavelength. Very large fluctuations of signal strength were associated with weather changes and attributed to a surface or elevated

duct. (Met. Abs. 4. 11-18)-C. E. P. B.

E-209 Lowell, P. D. ; Hakkarinen, W. and Randall, D.L., National Bureau of Standards

mobile low level sounding system. U.S. National Bureau of Standards, Journal of

Research, 50(1):7-17, Jan. 1953. 6 tables, 14 figs. , 12 refs. DWB-Details of

component parts, calibration procedure, flight computations and tests, etc. , are given in text, tables, wiring and other schematic diagrams and photographs. The

equipment is designed to measure pressure, temperature and moisture distribution

and gradients from the surface up to 2000 ft over different types of terrain. It is a combination of an improved wired sonde and Army SGM-1A Mobile Meteorological Station. For obtaining refraction index gradients used in tropospheric radiowave propagation measurements, this system has several advantages over radiosondes (too fast ascent), towers (300-400 ft maximum height) or wired sondes

(uncertain height and low ceiling). (Met. Abs. 8J-24)--M. R.

E-210 Megaw, E.C.S., Waves and fluctuations . Institution of Electrical Engineers,

London, Proceedings, Pt. 3, 100(63):l-8, Jan. 1953. 9 figs. , 14 refs. , 2 eqs.

DLC--This interesting lecture includes sections on turbulence and fluctuations

of refractive index, wave propagation through slightly inhomogeneous media,

intensity fluctuations or scintillation, and long range propagation of radio waves

by atmospheric scattering. Agreement between theoretical calculation and observations is good. (Met. Abs. 8J-25)--C.E.P. B.
49

E-211 Naito, K. , On the scattering of the plane electromagnetic wave by a continuous

inhomogeneity with spherical symmetry in a homogeneous medium. Papers in

Meteorology and Geophysics, Tokyo, 3(4):313-319, March 1953. 3 refs. , 28

eqs. DWB--The effect of atmospheric turbulence on microwave propagation is investigated theoretically. After integrating a vector wave equation for a plane

wave encountering a continuous inhomogeneity with a spherical symmetry in a homogeneous medium, the author defines the total scattering cross section (i. e. the ratio of the total scattered energy per unit time to the energy density of the

incident wave) and finds it to be proportional to the square of a qualitative magnitude of inhomogeneity. (Met. Abs. 8J-26)--G.T.

E-212 Naito, K. (Met. Res. Inst. ), On the influence of waterdrops in the air upon the

atmospheric radio refractive index. Papers in Meteorology and Geophysics,

4(34): 109-114, Dec. 1953. Summary p. 109. 2 figs. , 3 refs. , 11 eqs. DWB--

Radio refractive index is computed assuming Rayleigh scattering for a single

drop and approximate reactions between scattered waves. Relation to visibility

is shown. The resulting effect cannot always be disregarded as it is done in

the conventional formula, considering only pressure, temperature and vapor pressure. (Met. Abs. 8J-27)--A.A.

E-213 Norton, Kenneth A. , Transmission loss in radio propagation. Institute of Radio

Engineers, N. Y. , Proceedings, 146-152, Jan. 1953. Fig., 19 refs. , 21 eqs.

DLC --Ionospheric and tropospheric aspects of the problem are considered. Basis

for the discussion is author's definition of transmission loss to the ratio of the

power radiated from the transmitting antenna to the resulting signal power available from a loss-free receiving antenna. (Met. Abs. 8J-28)--W. N.

E-214 Perlat, A. and Voge, J., Attenuation des ondes centimetriques et millimetriques

dans l'atmosphere. (Attenuation of centimeter and millimeter waves in the atmosphere. ) Annales des Telecommunications, Paris, 8(12): 395-405, Dec. 1953.

7 figs. , 15 tables, 9 refs. DLC--The authors delineate the effects of the atmosphere on very short waves and the importance of atmospheric attenuation. In the first section results obtained by American and English research workers are surveyed in connection with absorption by rain, snow, hail, fog and clouds.

Attenuation by atmospheric ozone and by water vapor is also considered, taking

into consideration the effects of altitude and temperature. The second section

is a statistical study presenting precipitation, fog, water vapor and temperature

data of France and North Africa. In the third section a method is worked out for calculating atmospheric attenuation over a given path for specified percentages

of given time periods. --Transl. of authors' abstract-E. K.

E-215 Reen, J. H. , Summary of A. P.O. microwave propagation measurements on the

Sydney-Melbourne route (Aug. 1949-Oct. 1950). U.S. Navy Electronics Laboratory,

San Diego, Report, No. 409:72, 1953. 2 tables, ref. --A tabulated summary is

given of the comparative fading results over the radio propagation paths of

Sydney-New Madden, New Madden-Bowral, and Bowral-Goulburn, at frequencies

of 160, 3300 and 9400 Mc, respectively. Disturbed weather conditions were

prevalent on all paths. --N. N.
50

E-216 Rice, S.O. , Radio field strength statistical fluctuations beyond the horizon. Institute of Radio Engineers, N. Y. , Proceedings, 41(2): 274-281, Feb. 1953.

4 figs. , table, 8 refs. , 33 eqs. DLC--When a sinusoidal radio wave of extremely

high frequency is sent out by a transmitter, the wave received far beyond the

horizon is often observed to fluctuate. Here some of the statistical properties of

this fluctuation are derived on the Booker-Gordon assumption; namely, that the re- ceived wave is the sum of many little waves produced when the transmitter beam

strikes "scatterers" distributed in the troposphere. Expressions are obtained for the periods of the fluctuations in time, in space, and in frequency. These ex- pressions extend closely related results obtained by BOOKER, RATCLIFFE and

others. (Met. Abs. 8 J-29)- -Author's abstract.

E-217 Rider, G. C. , Some VHF experiments upon the diffraction effects of hills . Marconi Review, London, 16(109) :96-106, 1953. 7 figs. DLC --Experiments at 160. 2 Mc on propagation over steep hills show that the signal increase obtained

when passive repeater antennas are used may be satisfactorily predicted by the

method normally used for calculating the field in the shadow of a knife edge.

Passive repeaters are expected to be most useful in the UHF band. For prediction of field strength across a valley, when transmitter and/or receiver are close

to the hill, the spherical diffraction treatment gives results in closer agreement

with experiment than the knife-edge method. A preliminary survey of the polarization and direction of arrival of radio waves at receiver positions round the hill

was also made.

E-218 Robbins, R.L. (Bell Telephone Labs. , Inc. , N. Y. ), Measurement of path loss

between Miami and Key West at 3675 Mc . Institute of Radio Engineers, Transactions, Vol. AP-1, No. 1:5-8, July 1953. 6 figs. , ref. DBS --Experimental re- sults over five 130 mi paths are discussed here. The path losses observed,

especially over water in semi-tropical areas, were in agreement with those observed in other areas by BULLINGTON. Foreground terrains in relation to overland, over water paths and elevation of paths showed no difference; likewise,

diurnal and short term signal variations were similar to those observed elsewhere. (Met. Abs. 8J-30)--W. N.

E-219 Sadoun, B. , Propagation des ondes metriques a grande distance. (Long distance

propagation of meter waves. ) Annales des Telecommunications, Paris, 8(8-9):

299-308, Aug. /Sept. 1953. 19 figs. , 14 refs. , 2 eqs. DLC -Since Nov. 1952

the National Laboratory of Radioelectricity has been conducting long distance

recordings (300-700 km) of FM field strength at 88-100 Mc/s. It is found that

in addition to sporadic anomalous propagation phenomena there is, at long distance, a permanent fluctuating field whose mean level becomes more and more

stable with increasing distance. This field is far stronger than that obtained by

calculating the diffraction of waves around the earth. An explanation for the

phenomenon may be found by assuming a tropospheric scattering of radio waves.

--Transl. of author's abstract.

E-220 Schachenmeier, Richard, Die Erhffhunq der UKW-Empfangsfeldstarke durch eine

brechende Schicht. Inversion der Troposphere. (The increase in USW field intensity due to a tropospheric inversion layer. ) Archiv der Elektrischen Ubertragung,

7(10):485-491, Oct. 1953. 5 figs. , refs. , 41 eqs. DLC -Refraction in an inversion layer is considered in terms of an apparent increase in the effective height
51

of the sender. Calculations are made for different elevations of the receiver and

sender relative to the inversion layer. The influence of focusing of the radiation

in increasing the received field intensity is also considered. (Met. Abs. 8J-31)

--Electrical Engr. Abstract.

E-221 Smith, Ernest K. , Jr. and Weintraub, Stanley, Constants in the equation for at- mospheric refractive index at radio frequencies . U.S. National Bureau of Standards, Journal of Research, 50(1):39-41, Jan. 1953. 2 tables, 21 refs. , eqs.

DWB. Also in: Institute of Radio Engineers, N. Y. , Proceedings, 41(8):1035-

1037, Aug. 1953. 21 refs. , 11 eqs. DLC --Several radio propagation laboratories

have made improvements in microwave techniques and hence in the sets of constants used in calculations of atmospheric refraction of radio waves. It is suggested that a compromise set of constants such as are proposed in this article,

be adopted universally to avoid confusion hereafter. The expression to be used

in Radio meteorology is N = (77. 6/T) P + 4810 (e/T) , where P = total pres- sure (mb), e = partial pressure of water vapor (mb), T = absolute temperature.

This is considered accurate to 0. 5% up to 30, 000 megacycles at normal atmospheric temperature, pressure and humidity ranges. Values of E-l, N, K,

K2> and K- obtained by various authors (1931-1952) are tabulated. (Met. Abs.

8J-32)-M.R.

E-222 Strand, Kaj G. , Investigation of atmospheric refraction at low altitudes . U.S.

Arctic, Desert, Tropic Information Center, ADTIC Publication, No. A-102, Feb.

1953. 36 p. 3 figs. , 13 tables, 4 refs. DWB--Refractive indexes are computed from observations made in 1951 and 1952 at Dearborn Observatory about

60 ft from the west shore of Lake Michigan near Chicago, supplemented by

Joliet radiosonde data for selected days in 1951 and 1952. It is realized that

the air over Joliet is not the same as over Lake Michigan, yet conditions at 3000 ft are not so much different that data cannot be used interchangeably.

Observations of the Pleiades and Moon were used to determine refraction effect.

Techniques are described in detail and illustrated, and meteorological, as well as astronomical data presented in full. Pressure, temperature and dew point

are used for surface and up to 24, 000 ft and tabulated and measured values are compared, indicating that on individual nights observed values may differ by as much as 8% from computed values, when corrections for surface pressure and

temperature are applied. (Met. Abs. 8J-33)--M.R.

E-223 Swarm, H. M. ; Ghose, R.N. and Keitel, G.H. , Tropospheric propagation in

horizontally stratified media over rough terrain. Institute of Radio Engineers,

N. Y. , IRE Convention Record, Pt. 2 - Antennas and Communications, p. 77-84,

1953. 12 figs. , 3 refs. , 6 eqs. -The correlation of fields calculated on the

basis of the mode theory with measured signals for a 150 mi path is studied.

For the path considered with the assumption of linear index of refraction in the

atmosphere between 3000 and 10,000 ft heights, the field strength may be pre- dicted within 15 db for 90% of the time. The predicted field strength is based

on first mode propagation in which the gradient of the refractive index is the

primary variable. The atmosphere is assumed to be stratified vertically, but

homogeneous horizontally. The roughness of the terrain affects the heights at which the refraction is important at the middle of the path and is of particular

importance near the receiving site. The calculated field strength was always

lower than the measured field strength by a median value of 11. 5 db. Thus

apparently other mechanisms of propagation contribute to the increased field

strength by this median value. --Authors' abstract.
52

E-224 Swingle, Donald M. , Nomograms for the computation of tropospheric refractive

index. Institute of Radio Engineers, N. Y. , Proceedings, 41(3):385-391, March

1953. 3 figs. , refs. , 5 eqs. DLC--Three sets of nomograms permitting calculation of tropospheric refractive index gradient are presented. So far as is known, no similar charts have been made for discontinuity and gradient calculations.

All three have been designed about the standard radiosonde transmission, which

gives temperature, dew point temperature, and pressure at points where discontinuities occur in the vertical gradients of temperature or dew point temperature.

These nomograms are valid for all wavelengths greater than 1. 5 cm. (Met. Abs.

8 J-34) -Author's abstract.

E-225 Swingle, Donald M. (Signal Corps Eng. Lab. , Fort Monmouth, N. J. ), Reflections on electromagnetic waves from media of continuously variable refractive index.

(In: Conference on Radio Meteorology, Univ. of Texas, Austin, Nov. 9-12,1953,

Proceedings, Vol. 1 :IV-2, pub. 1953. 7 p. 3 figs. , 6 refs. , 17 eqs. DLC,

DWB--The theoretical analysis presented is based on the assumption of small

change in the refractive index and gives a good approximation of the lower atmosphere where the maximum possible change is of the order of 0. 3%. Extension

of the analysis may permit inclusion of both large changes of index and spherical waves. The method may be applicable to situations where no direct discontinuity

of the refractive index occurs. It is shown that a plane wave pulse containing an

integral number of cycles, propagating through a region of constant refractive

index gradients, produces no reflection. (Met. Abs. 8J-35)--W. N.

E-226 U.S. Army, Antennas and radio propagation. Its Technical Manual TM 11-666,

Feb. 1953. 225 p. 197 figs. , tables. DWB (M08 U58t)--The basic principles

of radio propagation are clearly presented, with many lucid schematic diagrams,

in Ch. 2 of this comprehensive manual. Ground wave propagation, the ionosphere, and sky wave propagation are taken up in 3 sections of Ch. 2, and

scores of definitions and questions appended in a fourth section. The various

types of tropospheric propagation (temp, inversions, humidity lapses, etc.)

and ionospheric reflection from O, E & F layers, day and night and with solar

flares, 11 yr and 27 day cycles, sporadic E, etc. , are outlined. (Met. Abs.

8J-36)-M. R.

E-227 U.S. Navy Electronics Laboratory, San Diego, Calif., Symposium on tropospheric wave propagation within the horizon, March 30-April 2. 1953. Its Report, 409, Sept. 3, 1953. 72 p. Figs. , tables, refs. , eqs. DLC--The symposium was divided into 3 sessions during which 14 papers were delivered as

follows: (1) Terrain effects (5 papers); (2) Refraction effects (6 papers); (3)

Combined and other effects (3 papers). These papers are reproduced in full or

in abstract in this report which also includes a list of names of all participants.

(Met. Abs. 8J-37)-W. N.

E-228 Unwin, R.S., Ultrashort wave field strength in a ground based radio duct.

Nature, London, 172(4384): 856 -857, Nov. 7, 1953. Fig. , 8 refs. DWB--Data

from New Zealand Canterbury Project show that duct width is the most important parameter in field strength beyond the horizon. Examples reproduced show

that as duct width increases from zero, field strength increases from a low value

up to a certain level (where first node goes from a leaky to a trapped state) after

which it increases very slowly or remains constant. The critical duct width in- creases from 27 m on 3 cm wavelength to 90 m on 60 cm but scatter is large.

(Met. Abs. 5. 3-324)-C.E.P.B.
53

Voge, Jean, Fadings et pertes de contact en ondes ultra-courtes, dus a la pre- sence de couches d'inversion. (Fadings and disruptions of contact in ultrashort

wave communication, due to inversion layers.) Academie des Sciences, Paris,

Comptes Rendus, 237(9) :491-493, Aug. 31, 1953. 3 refs. DWB--Results of a theoretical investigation of direct (standard) radio communication conditions

associated with inversions are summed up for various cases involving different

relative positions of the communicating stations and of inversion layers. (Met.

Abs. 8J-39)--G.T.

Voge, Jean, Fluctuations du champ electromagnetigue dues a la turbulence, a

l'extremite" d'un trajet de propagation en visibilite' directe. (Fluctuations of the

electromagnetic field due to turbulence on the end of a propagation trajectory

with direct visibility. ) Academie des Sciences, Paris, Comptes Rendus, 237

(4):351-353, July 27, 1953. 3 refs. DWB--Theoretical discussion for ultrashort

waves and light waves, applying the TAYLOR spectrum of turbulence, which

gives simpler solutions than proposed by MEGAW, who used KOLMOGOROV's

spectrum. (Met. Abs. 6. 3-16D--A. A.

Voge, J. , Note relative a la bande de freguences utilisable pour des transmissions a grande distance en ondes ultra courtes . (Note on the frequency band

usable for long distance USW transmission.) Annales des Telecommunications,

8(8-9) :308-311, Aug. /Sept. , 1953. 2 figs. , 5 refs. , 22 eqs. DLC--The theory

of S.O.Rice, according to which the field received over great distances depends

on scattering from a level directly visible from both the transmitter and receiver,

is applied to data of the Wrotham-Bagheux path. It is found that usable frequency

is independent and is in inverse proportion to distance, being of the order of 100

kc/s for a distance of 300 km. These figures have not yet been checked experimentally. --Transl. of author's abstract.

Weintraub, Stanley, Slide rule computes radio refractive index of air. Electronics, 26(1):182, 186, 190, 194, 196, 198, 200, Jan. 1953. 3 figs. , 2 refs. , eqs. DLC--The slide rule described and illustrated is claimed to have a pre- cision of + 0. 5 N-units under almost any conditions encountered in the troposphere. The slide rule was developed by the U.S. National Bureau of Standards

and facilitates tropospheric propagation studies. (Met. Abs. 8J-40)--W. N.

Wickizer, G.S., Field strength of KC'XAK. 534. 75 Mc recorded at Riverhead . N. Y. Institute of Radio Engineers, N. Y. , Proceedings, 41(1): 140-141, Jan. 1953. 6 figs. , 2 refs. --Field strength was recorded for 22 months over a nonoptical path at a distance of 33 mi. Overall variation was approximately 12 db

in winter and 33 db in summer, with relatively small variation in the median

level. On this transmission path, falling 10 db or more below the median occur- red during the summer months and was about evenly divided between daylight and

darkness for the normal hours of operation. --Author's abstract.

Wolin, Samuel (U. S. Naval Air Dev. Center, Pa. , Johnsville, Pa. ), Ray deflection through a medium having a continuously varying refractive index. Optical

Society of America, Journal, 43(5):373-375, May 1953. 2 figs. , foot-refs. , 28 eqs. DLC--A method is outlined for computing the ray deflection through a medium having a continuously varying refractive index. General equations are
54

developed by applying the calculus of variations to Fermat's principle of optics.

These equations are applied to the case of a dielectric material having a linear

variation with distance in its refractive index and also to the case of a foam

dielectric having a linear variation in density. A set of universal curves is pre- sented for the case of a plane dielectric sheet having a linearly varying dielectric constant. The general equations presented here can also be applied to the

design of lenses and optical devices having a continuously varying refractive

index. (Met. Abs. 8. 6-370) --Author's abstract.

1954

E-235 Barsis, A. P. , Comparative 100 Mc measurements at distances far beyond the

radio horizon. Institute of Radio Engineers, N. Y. , Convention Record, Pt. 1: 98-107,1954. 10 figs. , 5 refs. DLC (TK6541. 15) -Results of 100 Mc measurements are evaluated in terms of distributions of hourly medians of transmission loss. Transmitters were located at elevations of approximately 6200, 8800

and 14, 100 f. a.m. s. 1. on the eastern slope of the Rocky Mountains. Receiving

sites were located at distances of 230 and 400 mi from the transmitters. Various

types of antennas were employed for transmitting and receiving. The results of

studies of fading rate and fading range are reported for the 400 mi site by comparing signals received simultaneously on two different antennas. These results

are compared to those expected from the application of the tropospheric scatter- ing theory. (Met. Abs. 8 J-41) --Author's abstract.

E-236 Bean, Bradford R. and Meaney, Frances M. (both, National Bureau of Standards,

Boulder, Colo.), The monthly refractivity gradient for the United States and its

application to predicting the geographical and annual trend of VHF transmission

loss. (In: Conference on Radio Meteorology, Nov. 9-12, 1953, Univ. of Texas,

Supplement to the Proceedings, III-2, pub. 1954. 11 p. 5 figs. , table, 4 refs. , 2 eqs. ) DWB (M94. 7 C748p Sup. )--Climatological studies of VHF propagation

conditions all over the U.S. are under way, using the simple parameter A N (refractivity gradient from surface to K km above the surface) to correlate with the

transmission loss over the propagation path whose midpoint is over the weather

station in question. Other causes must be taken into account (roughness, distance, height of antenna, etc.). The present method reduces the month-to-month

and station-to-station uncertainty by taking out the average climatic effect.

Tables and curves based on 1950-52 data show effectiveness of method and

amount of variation. (Met. Abs. 8J-42)--M.R.

E-237 Bean, Bradford R. , Prolonged space-wave fadeouts at 1.046 Mc observed in

Cheyenne Mountain propagation program. Institute of Radio Engineers, N. Y. , Proceedings, 42(5): 848-853, May 1954. 8 figs. , table, 3 refs. , eq. DLC--

During the first year of continuous operation of the Cheyenne Mountain propagation program, recordings of 1,046 Mc fields at receiving locations within the

radio horizon have exhibited " fadeouts " or prolonged periods of attenuation

often in excess of 20 db below the monthly meridian level and lasting from a minute up to several hours. The occurrence of these fadeouts has been found

to coincide with widespread superrefraction as evidenced by enhanced signals

beyond the radio horizon and ground modification of the refractive index profile.

(Met. Abs. 8 J-43) -Author's abstract.
55

Bremmer, H. , The extension of Sommerfield's formula for the propagation of

radio waves over a flat earth, to different conductivities of the soil . Physic a, Amsterdam, 20(8) -.441-460, Aug. 1954. 4 figs. , 6 refs. , 54 eqs. DLC

(QC1. P38)--The influence of non-homogeneous soil conditions on the propagation of radio waves over a flat earth is investigated with the aid of an integral

equation based on Green's theorem. This equation applies to all types of distributions (also continuous) of the conductivity and of the dielectric constant

of the earth; it is essentially identical with the integral equation considered

by HUFFORD for the propagation over irregular terrain. (Met. Abs. 8J-44)

--From author's abstract.

-239 Carroll, Thomas J. , Overcoming the line-of-sight Shibboleth with the air and

high power. Institute of Radio Engineers, N. Y. , Convention Record, Pt. 1: 121-125, 1954. 3 refs. Also: Institute of Radio Engineers (Australia), Pro- ceedings, 16:107-112, April 1955. DLC --Gives a simple account of the reasons for both VHF and UHF trans-horizontal propagation and includes

some probable implications for the UHF television. The role of the troposphere has been grossly neglected in the earlier tropospheric propagation

theory. The crux is not in the shape of the index profile, but rather in making proper distinction in the mathematics between the inhomogeneous air

layer and the homogeneous void beyond. --W. N.

-240 Carroll, Thomas J. (M.I.T.), Tropospheric propagation well beyond the

horizon: a review. (In: Conference on Radio Meteorology, Nov. 9-12, 1953,

Univ. of Texas, Supplement to the Proceedings, 1-1, pub. 1954. 7 p. Fig. , 2 refs. ) DWB (M94.7 C748p Sup. ) -The author reviews the basic discoveries

that radio waves would propagate well beyond the horizon or the theoretical

distance calculated by mathematical formulas. The 4/3 (earth's radius) law

did not explain atmospheric effects produced by anomalous temperature and

humidity structure. Superrefraction, effect of turbulence in scattering rays into

the twilight zone, the duct theory (modes in the dielectric layer), and effect of

roughness of earth are considered. The mode theory operates well enough ex- cept when turbulent layers exist over the midpoint of the path, then an even

greater degree of propagation (though erratic) to distances can exist. Typical

propagation measurements for 93, 410 and 3000 Mc are shown on curves for distances up to 400 km. Isolated measurements at 1047, 3700 and 9375 Mc

are also shown on chart and all are compared with the theoretical curves for geometrical horizon, the 4/3 radius for 300 Mc, the 4 1/3 radius for 50 Mc

and free space (vacuum), respectively. (Met. Abs. 8J-46)--M.R.

-241 Crain, Cullen M. ; Gerhardt, J. R. and Williams, C.E. (all, Univ. of Texas,

Austin), A preliminary survey of tropospheric refractive index measurements

for U.S. interior and coastal regions. Institute of Radio Engineers, N. Y. , Transactions, Vol. AP-2, No. 1:15-22, Jan. 1954. 9 figs. , 5 refs. DBS-This

paper summarizes the results of approximately 700 tropospheric refractive index

soundings carried out between July 1952 and Dec. 1952, using aircraft mounted

direct reading refractometers. Extensive observations up to heights as great as 25,000 ft have been made in the Southern Ohio region and off the U.S. east and

west coasts. Preliminary statistical analyses on the occurrence of standard

and non-standard average gradients are presented together with qualitative

meteorological correlations. The existence of large scale index variations near certain cloud boundaries is confirmed and these are tentatively explained

in terms of the contrast between the free air refractive index and that of a vertically moving air current having a refractive index representative of some lower

atmospheric level. (Met. Abs. 8 J-47)- -Authors' abstract.
56

E-242 Deppermann, K. and Franz, W. , Theorie der Beuqunq an der Kuqel unter

Berifcksichtiqunq der Kriechwelle . (Theory of diffraction over a sphere with

particular consideration to the creeping wave. ) Annalen der Physik, Ser. 6,

14(6/8): 253-264, 1954. 5 figs. , 6 refs. , 5 eqs. -This theoretical paper is

based upon excerpts from Deppermann's dissertation, and deals with refraction

of acoustical and electromagnetic waves of an ideal reflecting sphere, as discussed in terms of the integral equations of the refraction theory. The interference of the creeping wave (skin effect) on the geometrically reflected wave

manifests itself as intensity maxima and minima which is demonstrated graphically. -W. N.

E-243 Feinstein, J. , Some information theory aspects of propagation through time

varying media . Institute of Radio Engineers, N. Y. , Convention Record, Pt. 1: 87-97, 1954. 3 figs. , 9 refs. , 69 eqs. DLC--The channel capacity of a communications system which utilizes wave propagation through a time varying

medium such as the ionosphere or troposphere is evaluated in terms of the statistical properties of the medium and of the noise. The signal fading in such

a system reduces the capacity. Information theory concepts are broadened to include the possibility of multiple reception at spaced receiving sites, and the

consequent increase in theoretical channel capacity is computed as a function

of the number of such sites. Current practices in the use of diversity reception and directional antennas are examined in the light of these results.

(Met. Abs. 8 J-48) -Author's abstract.

E-244 Feinstein, Joseph (U. S. Nat* 1. Bureau of Standards), Some stochastic problems

in wave propagation. Pt. 1. Institute of Radio Engineers, N. Y. .Transactions,

Vol.AP-2, No. 1:23-30, Jan. 1954. Pt. 2. Ibid., Vol.AP-2, No. 2:63-70, April

1954. 6 figs. , 87 eqs. DBS --This theoretical discussion deals first with some

effects of random height variations over a conductive surface upon reflected

wave energy, using methods of physical optics. Several aspects are determined. Next, the author treats the effects of the refractive index fluctuations on an emergent front within volume and subsequently generalized to a continu- ous medium. The effects upon properties of traversing waves are discussed in

Pt. 2. The results as applied to some tropospheric and ionospheric problems

are then discussed and found indicative and applicable. (Met. Abs. 8J-49)

»W. N.

E-245 Fine, Harry, An effective ground conductivity map for continental U.S . Insti- tute of Radio Engineers, N. Y. , Proceedings, 42(9): 1405-1408, Sept. 1954.

Fig. , table. DLC --Derivation and accuracy of the map adopted by the Federal

Communications Commission for use as of April 1954, is discussed here. The

map, designed on a 1 to 2,500,000 scale, features not less than 7000 paths

throughout the country. The true effective median path conductivity for distances less than 25 mi from transmitter is within 0. 59 and 1. 7 of the values

plotted. The map is available from the Govt. Print. Off. , Wash. ,D.C. for $3. 50 a copy. (Met. Abs. 8J-50)-W. N.

E-246 Franz, Walter, Uber die Greenschen Funktionen des Zylinders und der Kuqel . (Green's functions of cylinders and spheres. ) Zeitschrift fur Naturforschung,

9a(9): 705-716, Sept. 1954. 7 figs. , 6 tables, 8 refs. , 39 eqs. -This theoretical

discussion has bearing on the propagation of radio waves through the troposphere.

Reference is made to works by WATSON and VAN DER POL-BREMMER. --W. N.
57

Frundt, H.J. , Betriebsbereitschaft einer weit hinter den Horizont reichenden

UKW—Richtverbindunq. (Reliability of USW radio link extending far beyond the

horizon.) Telefunken Zeitung, 27(103): 41 -43, March 1954. 5 figs. , 6 refs. -- Some exercises and results obtained on the non-optical radio link Berlin-Harr

at 41 and 68 Mc/s are discussed. --W. N.

Ghose, Rabindra Nath and Albright, W. G. , VHF field intensities in the diffraction zone . Institute of Radio Engineers, Transactions, AP-2(l):35-38, Jan. 1954.

3 figs. , 8 refs. , 20 eqs. --Signal strengths are calculated and compared with

measured values. This analysis departs from others in the variation of form of

obtaining a solution to the wave equation. An exponential form of refractive

index distribution with height is presented. --W. N.

Gibbs, W. J. , Meteorological aspects of microwave propagation in Australia . Australia. Meteorological Branch, Meteorological Study, No. 1, June 1954.

14 p. 13 figs. , 6 refs. , 12 eqs. DWB--Superrefraction will occur in the lowest

layers of the atmosphere where there is a strong temperature inversion (-^ 0. 14°

C/m), a moderate temperature inversion and lapse of humidity, or a strong lapse

of humidity (vapor pressure gradient > —0. 3 mb/m). In Australia, superrefraction is likely to be associated with the "coastal front" (continental air overlying

denser marine air), subsidence inversions, inversions in continental air modified

over the sea, and nocturnal radiation inversions. Typical profiles of temperature,

vapor pressure, and refractive index gradient are shown. (Met. Abs. 8J-51)

-R.S.Quiroz.

Grant, Arthur S. G. (Met. Service of Canada, Ottawa), Notes on the atmospheric

refractive index in Canada from aircraft meteorological soundings . American

Geophysical Union, Transactions, 35(3): 508-510, June 1954. 3 figs. , 4 refs.

MH-BH--Calculations of the atmospheric refractive index for radio waves were made from aircraft soundings over a large area of northern Canada in connection

with the 1952 season of the shoran survey. A comparison is made between the

results and the NACA 60% relative humidity standard atmosphere. (Met. Abs.

6. 2-327) -Author's abstract.

Jasinski, W. and Berry, J. A. , Measurement of refractive indices of air, nitrogen , oxygen, carbon dioxide and water vapor at 3360 Mc/s . Institution of Electrical

Engineers, London, Proceedings, Pt. 3, 101(73) :337-343, Sept. 1954. 3 figs. , 2 tables, 19 refs. , 8 eqs. DWB--Refractive indexes n were measured by resonant frequency of a cavity filled with the gas, checked by a crystal-controlled

frequency standard. Values of (n - 1) X 10 at C, 760 mm, correct to about + 0. 2 were: Dry air free of C02> 288. 3; Nitrogen 294. 5; Oxygen 266. 2: C02

\Oa 494. 6. Water vapor at 20 C and 10 mm gave 61. 3 + 0. 1. The permanent electric moment of the water molect

(Met. Abs. 6. 5-350)-C.E.P.B.

18

trie moment of the water molecule was calculated as (1.845) X 10 e. s. u

E-252 Kazansky, B. , Vliv pove'trnostnich pomeru na televisni priiem. (Influence of

weather conditions on television reception.) Meteorologicke Zpravy, Prague,

7(2):53-55, 1954. DLC. From the Russian original by M. DOLUKHANOV in

Radio, No. 9:41-44, 1952. --Sums up knowledge on ultrashort radio wave
58

propagation beyond the horizon and its meteorological causes. Television re- ception beyond the normal range is attributed mainly to abnormal refraction and

sudden drops in temperature. (Met. Abs. 8J-53)--G.T.

E-253 Kirby, R.S.; Harman, J.C.; Capps, F. M. and Jones, R. N. , Effective radio

around conductivity measurements in the United States. U.S. National Bureau

of Standards, Circular 546, Feb. 26, 1954. 87 p. almost entirely maps. DLC--

Maps are presented showing the results of effective ground conductivity measurements made by various broadcasters and consulting engineers throughout the

United States. Over 7000 radials are shown on the maps, and provisions have

been made for entering new measurements, as the results become available. Due

to the complexity of ground wave propagation over an inhomogeneous earth, the

determination of effective ground conductivity over a given radial strictly applies

only at the frequency at which the measurements were made. (Met. Abs. 8J-54)

--From authors' abstract.

E-254 Lauter, E. A. and Klinker, L. , Long distance U. S. W. reception. Nachrichtentechnik, 4(6):242-247, June 1954. --Records of field strength measurements made

at Kuhlungsborn since 1951 are analyzed in respect of diurnal variations of mean

level, sudden changes in level, and rapid fluctuations. Data cover transmissions in the 87. 5-100 Mc band over two 200 km land paths and one 180 km sea

path, and hourly records of some 30 transmissions over distances 50-500 km.

Refraction theory accounts satisfactorily for propagation over distances up to three times the optical range; partial reflections can give field strengths below

the horizon only 20-30 db below the level for free space propagation; relatively

high mean field strength at great distances during unstable atmospheric conditions is ascribed to scattering process. (Met. Abs. 8 J-55) --Abstract from Wireless Engineer.

E-255 Peterson, D. W. , Bibliography of non-contract literature on tropospheric propagation. Radio Corporation of America. Engineering Products Div. , Camden,

N. J. , Contract DA-36-039-Sc-5663, Study of Army Television Problems, Vol. 3,

May 15, 1954. 146 p. --The bibliography contains about 500 entries comprising

IRE abstracts, and other American symposium, reports and dissertations during

the period 1949 and well into 1953. It may be regarded as a supplement to the

Cornell Univ. Final Report, Pt. I, April 1951, Bibliography of reports on tropospheric propagation. The annotated references are listed in chronological order, cross referenced by the author index and an excellent subject index. (Met. Abs.

8J-56)-W. N.

E-256 Randall, D.L. (National Bureau of Standards, Wash. ,D.C), A study of some

of the meteorological effects on radio propagation at 96. 3 Mc between Richmond , Va. and Washington. D.C . American Meteorological Society, Bulletin, 35(2):

56-59, Feb. 1954. 4 figs. , 4 refs. DWB--This study was made to investigate

the relationship of surface meteorological data and corresponding surface refractive indices to radio field strengths in the FM frequency band. For meteorological observations during which the wind speeds were equal to or greater than 10

mph, and when fronts, low overcast clouds (less than 5000 ft), rain, thunderstorms and fogs were excluded, a 0. 70 correlation coefficient was found between hourly surface refractive index and hourly median field strength over a Washington-Richmond path at a frequency of 96.3 Mc. (Met. Abs. 8J-57)

--Author's abstract.
59

Riddle, R.L.and Ammerman, C.R. (both, Penna. State Univ. , Dept. of Elec.

Engr. ) , A preliminary study of fading of 100 Megacycle FM signals . Institute

of Radio Engineers, Transactions, Vol.AP-2, No. 1:30-34, Jan. 1954. 7 figs. , 9 refs. , eqs. DBS--This analytical study includes experimental transmission

data from the mountainous path between Pittsburgh, Pa. and State College, Pa.

The tropospheric scatter volume in this path is about 39 mi west of State College and at about 3800 ft altitude. BOOKER and GORDON'S troposphere model

is strengthened. It is indicated that this study is an embryonal method of con- tinuous measurements of wind velocities and/or to determine the extent to which

turbulence is present. (Met. Abs. 8J-58)--W. N.

Saxton, J. A., Basic ground wave propagation characteristics in the frequency

band 50-800 Mc/s . Institution of Electrical Engineers, London, Proceedings,

Pt. Ill, 101(72):211-214, July 1954. 4 figs. , 22 refs. , 3 eqs. Discussion

p. 221-224. DLC--The relation between existing experimental data on transmission at very high frequencies, at distances such that variations in atmospheric

refractive index are of little significance, and fundamental propagation theory

is discussed. An empirical correction for the difference between the field

strengths observed over irregular terrain and theoretical values is given, and

basic ground wave characteristics for the frequency band 50-800 Mc/s are suggested which should be applicable except in very mountainous country or

in densely built-up areas. Over this frequency band, and for distances inside

the normal horizon, it appears that there is very little variation of median field

strength with frequency for a given effective radiated power. --Author's abstract.

Saxton, J. A. and Harden, B. N. , Ground wave field strength surveys at 100 and

600 Mc/s. Institution of Electrical Engineers, London, Proceedings, Pt. Ill, 101(72): 215-221, July 1954. 5 figs. , 15 refs. Discussion p. 221-224. DLC--

The paper gives the results of an experimental investigation of the effects of

irregular terrain on ground wave propagation at frequencies near 100 and 600

Mc/s, particular attention being paid to propagation characteristics at the

higher frequency. Together with other work, these results clearly show that as the frequency increases so also does the amount by which the median observed field strength for any distance falls below the smooth earth theoretical

value. --Authors' abstract.

Silverman, Richard A. and Balzer, Martin, Statistics of electromagnetic radiation scattered by a turbulent medium. Physical Review, N. Y. , 96(3): 560-563,

Nov. 1, 1954. 6 eqs. --Univariate and bivariate amplitude distributions are calculated employing Villars and Weisskopf's theory, and compared with experiment. The univariate distribution is Raleigh, and the bivariate is used to derive

a relation between the amplitude correlation function and the velocity correlation

function as appearing in von Weizsacker-Heisenberg's statistical theory of tur- bulence. --W. N.

Straiton, A. W. ; Gerhardt, J. R. and Tolbert, C. W. , Propagation of millimeter

radio waves in low level overwater ducts. Texas. Univ. Electrical Engineering

Research Lab. , Contract Nonr 375(01), Report, No. 74, Oct. 15, 1954. 19 p. 12+8 figs. (incl. photos), table, 14 refs. DWB--Radio signal strength measure- ments are reported for propagation tests in a low level overwater duct. A wavelength of 4. 3 mm was used on a 7 mi path, a wavelength of 8. 6 mm on paths up

to 24 mi and a wavelength of 3. 2 cm on paths up to 44 mi. All transmitter and
60

receiver heights used were less than 15 ft. The signal level was found to be

less than the free space value with decay rates per mile given approximately

as follows:

Wavelength Decay Rate in db per Theoretical Oxygen

Mile Illative to Free and Water Vapor

Space Loss in db per Mile

4. 3 mm 3 2. 8.6 mm 0.7 0.4

3. 2 mm 0. 3 0.

The fluctuation range increased sharply as the wavelength decreased from 3. 2

cm to 8. 6 mm and increased still more as the wavelength decreased to 4. 3 mm.

The range of the fluctuation also increased approximately in proportion to distance. (Met. Abs. 8 J-59) --Authors' abstract.

E-262 Suda, K. , Field strength calculations—New Method for mixed paths. Wireless

Engineer, 31(9):249-251, Sept. 1954. 2 figs. , 4 refs. , 4 eqs. DLC -A simple

method for the calculation of field strength over mixed paths is explained with

the aid of a comparison with measured values of field strength. An equivalent

conductivity is obtained from the "numerical distance" and field strength is calculated easily by conventional curves. --Author's abstract.

E-263 Tao, Kazuhiko (Radio Res. Labs. , Tokyo), On the propagation of ultra short

waves beyond the horizon. Japanese Journal of Geophysics, Tokyo, l(l):27-79,

May 1954. 41 figs. , 2 tables (1 fold. ), 42 refs. , numerous eqs. DWB--A long

and thorough paper covering in the first part, the theory of tropospheric propagation of high frequency radio waves beyond the horizon, considering 3 types of

propagation conditions: diffraction by a discontinuity, reflection from a nocturnal inversion (at 150-300 m height, as a rule), and double reflection from an

inversion and the ground. Field strength distance curves are given in 4 elaborate nomograms, and schematic models presented to illustrate relation of field

strength to various vertical profiles. In the second part the observed variations

of field strength between Kokubunji and Hiraiso, crossing Tateno Geological

Observatory, are analyzed to find seasonal, diurnal, and meteorological variations of 150 and 60 Mc/s waves. Examples are described and illustrated.

Daily aerological soundings at Tateno furnished refractive index data for noontime, and captive balloons were used on Nov. 17, 18, 20 and 22, 1952 to obtain diurnal variations in refractive index gradient up to 200 m. The conclusion

was that thin layers (20, 40 or 60 m thick, for instance) do not carry the maximum signal strength, but that layers about 160 m thick are optimum. Signal

strength is usually weakest about noon and reaches a remarkably high value at night. This latter cannot be explained by a linear refraction-diffraction theory, so a bilinear theory is proposed. Signals are stable when atmosphere is stable

and vice versa. Conditions during different types of air masses and during passage of fronts are discussed and illustrated by 3 hourly synoptic charts for

Nov. 17, 18 and 20, 1952, and time cross sections of mixing ratio and potential

temperature as well as hourly refractive index profiles and An, AT, a *

f ana

> other parameter curves. (Met. Abs. 8J-60)--M.R.
61

E-264 Tolbert, C. W. ; Britt, CO.; Tipton, CD. and Straiton, A. W. , Propagation of

4. 3 millimeter radio waves on 3. 5 and 7 mile paths . Texas. Univ. Electrical

Engineering Research Laboratory, Contract Nonr 375(01), Contract Nonr 071 032,

Report No. 73, Aug. 6, 1954. 15 p. 8 figs. , 5 refs. Available ASTIA, AD

38950. --Propagation measurements are reported for frequencies of 69. 5 and 70. 1 kilomegacycles per second over 3. 5 and 7 mi paths in the vicinity of Austin,

Texas. These measurements indicate that the oxygen absorption is somewhat

less than that predicted by VAN VLECK (1) whereas the water vapor absorption

is several times that predicted. The magnetron transmitter, the crystal video

receiver, and the associated equipment used for the test are described in the

report. (Met. Abs. 8 J-61) -Authors' abstract.

E-265 Villars, F. and Weisskopf, V.F. , Scattering of electromagnetic waves by turbulent atmospheric fluctuations. Physical Review, N. Y. , 94(2) -.232-240, April 15,

1954. 2 figs. , 7 refs. , 54 eqs. —Application of the statistical theory to tropospheric and ionospheric density fluctuations. The dominant role of humidity

fluctuation in tropospheric scattering is demonstrated. --W. N.

E-266 Wait, James R. , Radiation from a vertical electric dipole over a stratified

ground. Pt. 1. Institute of Radio Engineers, N. Y. , Transactions, AP-1(1):9-11,

July 1953. 2 figs. , 11 eqs. , 6 refs. Also: Wait, J. R. and Fraser, C.G. , Pt. 2. Ibid., AP-3:144-146, Oct. 1954. 2 figs. , table, 5 refs. , 7 eqs. DLC--Pt. 1,

expressions for the radiation fields at low frequencies of a vertical electric

dipole situated on a horizontally stratified ground are derived. It is indicated

that the well known numerical results for the homogeneous ground can also be

employed for ground wave propagation over a plane conductor composed of any

number of parallel layers by suitably defining an effective numerical distance.

In Pt. 2, further results are given for the problem of a vertical electric dipole

situated over a horizontally stratified conductor. It is pointed out that under

certain conditions the surface wave field intensity for a stratified conducting

ground is greater than the corresponding case for a perfectly conducting ground.

Numerical values for the attenuation factor are also given. (See ref. E-428)

--Author's abstract.

1955

E-267 Ames, L.A. ; Newman, P. and Rogers, T.F. (all, Air Force Cambridge Res.

Center, Mass.), VHF tropospheric overwater measurements far beyond the

radio horizon. Institute of Radio Engineers, N. Y. , Proceedings, 43(10):1369-

1373, Oct. 1955. 6 figs. , 13 refs. DLC --Using a high power radar type trans- mitter near Boston, Mass. , point-to-point measurements have been made at a frequency of 220 mcps on 200 and 400 statute-mi overwater paths extending

along the east coast. Comparisons are made with similar data available for overland paths. Correlations between the shorter path field strength data and

sea echo back scatter near the transmitter site are indicated. Airborne field

strength measurements have also been made out across the North Atlantic

Ocean to a distance in excess of 400 mi; the variation of field strength with

distance is graphically displayed by this technique. (Met. Abs. 8J-63)

--Authors' abstract.

E-268 Ames, L. A. and Rogers, T. F. , Available bandwidth in 200 mi VHF tropospheric

propagation. Institute of Radio Engineers, Transactions, AP -3(4): 217-218,

Oct. 1955. Fig. , 8 refs. DBS --Television signals radiated from the Empire State

Building, New York, over the frequency range 210-216 mcps were received 196 mi
62

away in Scituate, Mass. A study of the signals received leads to the conclusion

that the propagation medium allows an effective bandwidth of some 3-4 mcps at vhf for 200 mi even during the weaker signal level periods predominantly characterized by the extra diffraction type propagation mode. This is in agreement with

tropospheric scatter propagation theory. --G. T.

E-269 Anderson, L. J. and Gossard, E. E. , Prediction of oceanic duct propagation from

climatological data. Institute of Radio Engineers, N. Y. , Professional Group on Antennas and Propagation, Transactions, Vol.AP-3, No. 4:163-167, Oct. 1955.

5 figs. , foot-refs. DLC. Also issued as: U.S. Navy Electronics Laboratory,

San Diego, Calif., Research and Development Report, No. 654, Dec. 14, 1955.

DWB- -Techniques are described for predicting the effect of the "oceanic duct"

in increasing the coverage of low sited microwave radars. Prediction is made on

a monthly basis using statistical data on sea temperature, air temperature, humidity, and wind speed. A large area in the northwest Pacific is used to illustrate

the methods used. The basic prediction approach is to deduce refractive index

profiles from available data parameters and to use SCHELKUNOFF's ducting

criteria to predict radar propagation effects. Monthly contours are then drawn

over the area for each radar band showing the probability of extended coverage.

(Met. Abs. 8. 1-393) -Authors' abstract.

E-270 Aono, Yuichiro and Muramatsu, Kinya, Measurement of field intensity of ground

wave over mixed paths. Japan. Radio Research Laboratories, Tokyo, Journal,

2(7): 51-58, Jan. 1955. 10 figs. , 2 tables, 13 refs. DWB--This paper describes

the results of the measurement carried out near Tokyo of the field intensity of

ground wave on the frequencies 1. 85, 2. 5 and 4 Mc. The measured values are compared with the calculated values after the methods developed by a number of

workers. From this comparison it is derived that the new theory which has been

developed theoretically by K.FURUTSU, a member of our Laboratories in cooperation with the experiments, can give the most reasonable explanation to the propagation characteristics of ground wave. (Met. Abs. 8 J-64) --Authors' abstract.

E-271 Barghausen, A.F. ; Decker, M.T.and Maloney, L.J. , Measurements of correlation, height gain, and path antenna gain at 1046 megacycles on spaced antennas

far beyond the radio horizon. Institute of Radio Engineers, N. Y. , Convention

Record, Pt. 1:78-81, 1955. 5 figs. DLC (RK 6541 .15) -Studies made and re- ported by the National Bureau of Standards in 1953 on the correlation of 1046 Mc

radio fields on spaced antennas at distances far beyond the radio horizon are supplemented by more recent measurements. Measurements were made on the

NBS Cheyenne Mountain transmission path in Colorado and Kansas at a frequency

of 1046 Mc, the receiving location being at an angular distance of 27 milliradians

(for standard atmosphere), i. e. approximately 150 mi beyond the transmitter radio

horizon. In addition to the correlation of instantaneous fields, the correlation of

hourly median fields and the diurnal variation of the received signal are shown.

(Met. Abs. 8J-65)--From authors' abstract.

E-272 Barsis, A. P.; Herbstreit, J. W. and Hornberg, K. O. , Cheyenne mountain tro- pospheric propagation experiments . U. S. National Bureau of Standards, Circular

No. 554, Jan. 3, 1955. 39 p. 46 figs. , 2 tables, 18 refs. , eqs. -Measurements

at five frequencies from 92 to 1046 Mc/s were conducted over 393 and 617 mi

paths. The studies include effects of rough terrain, dependence on transmission

loss on refractive index profiles, height gain functions and application of relative theories, e.g. the new theory of propagation embodying BOOKER-GORDON'S

scattering principles as extended by STARAS. --W. N.
63

E-273 Bean, Bradford R. (Central Radio Propagation Lab. , National Bureau of Standards, Boulder, Colo.) and Meaney, F. M. (formerly of same Lab. ), Some

applications of the monthly median refractivity gradient in tropospheric propagation. Institute of Radio Engineers, N. Y. , Proceedings, 43(10):1419-1431,

Oct. 1955. 9 figs. , 6 tables, 12 refs. , numerous eqs. DLC--A consistent

correlation has been found between the monthly median values of 100 Mc trans- mission loss and an atmospheric parameter aN which is determined from standard radiosonde observations. AN is defined as the difference between the re- fractivity at the earth's surface and at one kilometer above the earth's surface.

A.N is determined from the mid-point of the propagation path and is taken to represent an effective gradient of the refractive index. It is found to yield

correlation coefficients with transmission loss of about 0. 7 even in the far

scattering region. This correlation is also used to derive estimates of the

annual, geographic, and terrain variances of the transmission loss. Six year

average values of AN are presented for the United States and can be used as an aid in the prediction of the annual cycle of 100 Mc transmission loss. The

possibility of using surface observations of N for times of day other than the

radiosonde observation hours is examined and found to be encouraging. One

of the major conclusions is that the observed dependence of transmission loss

upon AN is five times greater than that indicated by standard propagation

theory. (Met. Abs. 8 J-67) -Authors' abstract.

E-274 Birnbaum, George and Bussey, H. E. (both, Nat'l. Bureau of Standards, Boulder,

Colo. ), Amplitude, scale, and spectrum of refractive index inhomogeneities

in the first 125 meters of the atmosphere. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1412-1418, Oct. 1955. 3 figs. , 2 tables, 13 refs. , eqs.

DLC--An extensive series of observations was obtained with two refractometers

and meteorological equipment installed on various levels of a 128 m tower at the Brookhaven National Laboratory, Long Island, New York. One of the refractometers was equipped with a multiple cavity unit for the study of correlation

between two positions in the horizontal direction. The errors arising from the

exposure of the cavity to the atmosphere and its ventilation were investigated.

The amplitude of the refractive index variations could be correlated with various

meteorological conditions. From the experimentally determined cross correlation

coefficient, and assuming that its variation with distance is given by the exponential (Taylor) form, scales in the neighborhood of 60 m were obtained. A crude

analysis of the data indicated that the intensity of the refractive index inhomogeneities varied, on the average, as the 1.6 power of their size. (Met. Abs.

8 J-68) -Authors' abstract.

E-275 Booker, H.G. and de Bettencourt, J. T. (both, M.I. T.), Theory of radio trans- mission by tropospheric scattering using very narrow beams . Institute of Radio

Engineers, N. Y. , Proceedings, 43(3): 281-290, March 1955. 16 figs. , 8 refs. , 36 eqs. DWB--Calculations have been made for communication over a 300 km

path between antennas, each consisting of a paraboloid of diameter 100 A. It is assumed that, under normal atmospheric conditions, transmission over this

distance is due to scattering by atmospheric irregularities and that the scatter- ing phenomena are described by the formula used by BOOKER and GORDON.

Over this path, the effect of spread in the direction of arrival of scattered power

should become noticeable for beamwidths less than about 1. 5 degrees. For the

0. 73 degree beams assumed, spread in the angle of arrival should show up quite

markedly for synchronized beam swinging—that is, when the beams at both trans- mitter and receiver are swung simultaneously so that their axes continue to intersect, When the beams are swung 1 degree to one side of the great circle path,
64

the reduction in power received should be about 7 db, as compared with more

than 40 db that would occur for propagation purely in the vertical plane containing transmitter and receiver. Narrowing the antenna beams to very small values

is an important key to increasing circuit radio frequency bandwidth capability,

although at the expense of increasing antenna " aperture -medium coupling loss"

(so-called "gain loss"). For the assumed circuit average bandwidth should be

about 6 mcp, the loss being of the order of 10 db. For beams much larger than

1. 5 degrees, the bandwidth should be limited by the medium to about 3 mcp,

with negligible loss. General formulas are given from which the important

characteristics of any such communication link can be predicted. (Met. Abs.

8 J-69) -Authors' abstract.

E-276 Bray, W. J. ; Hopkins, H. G. ; Kitchen, F.A. and Saxton, J. A. , Review of long

distance of radio wave propagation above 30 Mc/s . Institution of Electrical

Engineers, London, Proceedings, Pt. B, 102(l):87-95, Jan. 1955. 3 tables, 61

refs. DLC--The purpose of the paper is to summarize the present state of knowledge concerning the factors affecting long distance radio wave propagation at frequencies above 30 Mc/s. Attention is drawn to various ionospheric and tropospheric propagation mechanisms and their broad characteristics. The account of

these special processes is preceded by Sections dealing with selected aspects

of "normal" propagation. A comprehensive bibliography is included. (Met.

Abs. 6 D-277) -Authors' abstract.

E-277 British Institution of Radio Engineers, London, Abstracts of papers which have

appeared in the Journal over the past 15 years (v. 1-15, 1939-1955). London,

Pub. by the Institution, 1955. 48 p. 395 abstracts in Decimal Classification

order. --The abstracts cover the principal papers published in the past 15 yrs

in this journal which, prior to 1939, was referred to as "The Proceedings".

The sections of radio meteorology including propagation and instrumentation

are listed under Radio Communication (621. 396) and subdivided according to the latest amendments to the U.D.C. system. (Met. Abs. 14. 7-112) --W. N.

E-278 Brocks, Karl, Per Brechungsindexgradient fur elektromagnetische Wellen (Cmbis M-Band) in der maritimen Grenzschicht der Atmosphare, I. (The gradient of

refractive index for electromagnetic waves (cm- to m-band) in the maritime boundary layer of the atmosphere, Pt. 1.) Deutsche Hydrographische Zeitschrift, 8(5):

186-194, 1955. 4 figs. , 3 tables, 9 refs. , 18 eqs. German, English and French

summaries p. 186-187. Also: Brocks, Karl and Hasse, Lutz, Pt. 2 (Summary,

diagrams and tables). Ibid., 9(5):217-221, 1956. 3 fold plates, 2 tables, 5

refs. , 8 eqs. German, English and French summaries p. 217. DWB—The vertical

gradient of the modified refractive index is correlated with the air-water temperature difference and the vertical stratification of water vapor. These correlations

enable the mean vertical gradient of refractive index in the duct in the lower

decameter above the surface to be calculated. Tables and diagrams are given

for practical application, with values for summer and winter at Weather Ship "D"

as an example. In Pt. 2, further aids are given for computing the refractive index

above the sea. These are: vapor pressure (mb) from dry and wet bulb temperatures, saturation vapor pressure and relative humidity from vapor pressure and

dry bulb temperature, and N = ( n - 1) 106 (n = refractive index) from dry bulb

and wet bulb or water temperature (salinity 35%). A short method is described

for computing curves of refractive index from air temperature, water content,

v/ind velocity, sea temperature and salinity. (Met. Abs. 8 J-122)--C. E. P. B.
65

E-279 Bullington, Kenneth (Bell Telephone Labs. , N. Y. ), Characteristics of beyondthe-horizon radio transmission. Institute of Radio Engineers, N. Y. .Proceedings,

43(10): 1175-1180, Oct. 1955. 5 figs. , 35 refs. DLC--This paper summarizes

the principal characteristics of tropospheric transmission beyond the horizon and

compares them with some of the properties of ionospheric scatter transmission.

Quantitative results are given on the dependence of the average signal level on

distance and frequency, fading phenomena, band width capabilities and realizable antenna gain. A short historical summary of beyond horizon tropospheric

transmission is also included. (Met. Abs. 8 J-71)--Author's abstract.

E-280 Bullington, K. ; Inkster, W. J. and Durkee, A.L. , Results of propagation tests

at 505 Mc and 4090 Mc on beyond horizon paths . Institute of Radio Engineers,

N. Y. , Proceedings, 43(10): 1306-1316, Oct. 1955. 18 figs. , 3 tables, 2 refs.

DLC--This paper gives the results of some radio propagation tests which were made on two beyond horizon paths in Newfoundland. During these tests simultaneous transmissions at 505 Mc and 4090 Mc over a 150 nautical mile path were measured for a full year, and transmission at 505 Mc over a 255 mi path

was measured for a period of 5 months. Both of these paths were partly over land and partly over water. Long term median signal levels and fading statistics for the two paths are given, as well as the results of some measurements

of the improvement obtained from space diversity reception and the gain realized

from large (28 ft) antennas on the 150 mi path. The test results provide further

evidence of the feasibility of using UHF beyond horizon links in communication

systems. (Met. Abs. 8 J-70)--Authors' abstract.

E-281 Campen, Charles F. and Cole, Allen E. , Tropospheric variations of refractive

index at microwave frequencies. U.S. Air Force. Cambridge Research Center,

Air Force Surveys in Geophysics, No. 79, Oct. 1955. 76 p. 46 figs. , 4

tables, 44 refs. , 13+19 eqs. DWB, DLC--The effect of gross variations in

tropospheric refractive index on the accuracy of radio guidance systems for high altitude vehicles is discussed. Refractive index profiles prepared from

radiosonde observations taken for 3 summer and 3 winter days at stations in

different geographical locations in North America and representing various

types of air masses are compared with a standard index of refraction curve derived from the ICAO Standard Atmosphere. Variations of the index at the

ground, at 20 kilofeet, the average of the index from the ground to 25 kilofeet

and the differences between these and the standard index are given. It was

found that the index varied by 135 N units at the ground, by 21 N units at 20

kilofeet, and that the average index from the ground to 25 kilofeet varied by

35 N units. When categorized by air mass type, by location, or by time intervals, variations within any of these categories were much smaller. Differences

between the computed indices and the Standard Index ranged from + 71 to —64 N

units at the ground, from + 17 to —4 N units at 20 kilofeet. The differences between the averages of the index from the ground to 25 kilofeet and the average

of the standard index ranged from +23 to —12 N units. Correlation of these

average index data with surface index data was found to be very good. A cor- relation coefficient of 0. 98 was obtained. For the scattergram a regression curve was drawn which showed a standard estimate of error of only 5 N units.

Sample calculations of refraction errors were made which show use of the index

data for correction of these errors. (Met. Abs. 8 J-72) --Authors' abstract.
66

E-282 Carroll, T. J. and Ring, R. M. (both, MIT, Lincoln Lab. .Lexington, Mass.),

Propagation of short radio waves in normally stratified troposphere . Institute of

Radio Engineers, N. Y. , Proceedings, 43(10): 1384-1390, Oct. 1955. 3 figs. , 24 refs. , eqs. DLC --Experiments of the past decade give stronger fields well

beyond the horizon than are calculated by the 4/3 airless earth approximation.

Post war work on the theory of the WKB approximation for wave propagation in

slowly varying inhomogeneous media, and the peculiar results for eigenvalues

of the bilinear refractive index profile offer valuable clues in the search for an

oversight in conventional propagation theory. If the absolute value, as well as

the gradient of the refractive index at the earth's surface be specified, with a refractive index profile which tapers to vacuum at some arbitrarily large height,

then allowed modes of the wave equation permit the field to be calculated within,

just beyond, and well beyond the horizon, in agreement with many vhf and microwave experiments. Modes thus calculated are supported by ordinary coherent

molecular scattering in normal air dielectric layer. At times, superrefraction

and macroscopic turbulence are additional mechanisms for propagation deep

into the shadow of the earth bulge. (Met. Abs. 8. 3-343) --Authors' abstract.

E-283 Chisholm, J.H. ; Portmann, P. A.; de Bettencourt, J.T. and Roche, J.F. (all,

M.I.T. Lincoln Lab. , Lexington, Mass.), Investigations of angular scattering

and multipath properties of tropospheric propagation of short radio waves beyond

the horizon. Institute of Radio Engineers, N. Y. , Proceedings, 43(10):1317-

1335, Oct. 1955. 28 figs. (incl. photos), table, 23 foot-refs. , eqs. DLC--

Experiments designed to investigate the potential communications capacity of

UHF and SHF tropospheric propagation beyond the radio horizon were conducted

by the MIT Lincoln Laboratory on circuits from 161 to 188 mi in length along the

coastal regions of the northeastern United States. Some of these tests were made in cooperation with the Bell Telephone Laboratories and the late E.H.ARMSTRONG. A study of the following aspects of tropospheric propagation was con- sidered necessary in order to gain a better understanding of the factors involved

in design of communications systems: 1) the extent of useful communication

bandwidths; 2) variation of UHF and SHF median signal levels over a full sea- sonal cycle; 3) the range and rates of fading; 4) the effective gain of highly

directional antenna systems; 5) the effect of multipath propagation on modulated signals; 6) the polarization properties of scattered fields and 7) the

angular dependence of scattered fields. Such experiments made from 1953 to 1955 have confirmed the utility of tropospheric circuits for wideband communication systems and have provided information useful in the evaluation of tropo- spheric propagation mechanisms. (Met. Abs. 8 J-75) -Authors' abstract.

E-284 Collier, James S. (57 Chapel Ave. , Buffalo, N.Y.), Upper air conditions for

two meter DX: temperature and water vapor content soundings for some famous

dates. QST, West Hartford, Conn., 39(9):16-18, Sept. 1955. 7 figs. , ref. DLC --Synoptic weather maps give good clues to the conditions ideal for superrefraction of VHF (2 m) radio waves, but upper air soundings are the only sure

indicators since they show existence and location of steep humidity gradients.

An example of normal (nonsuperrefractive) temperature and humidity sounding,

and 6 other soundings (Joliet, Albany, Pittsburgh, Toledo and Charleston, etc.

)

show conditions which give two meter DX. The Charleston sounding indicates no humidity gradient (July 23, 1949) at a time when Toledo shows a marked

gradient, indicating cause of nonreception at Charleston when conditions in the

Northern States were good. (Met. Abs. 8J-76)--M.R.
67

E-285 Crain, CM. (Electrical Engrg. Res. Lab. , Univ. of Texas), Survey of airborne

microwave refractometer measurements. Institute of Radio Engineers, N. Y. , Proceedings, 43(10):1405-1411, Oct. 1955. 12 figs. , 13 refs. DLC--This

paper presents a summary of airborne refractive index measurements which have

been made at many locations in the United States both over land and off the

east and west coasts, by several organizations. Included are the results of

studies of the mean vertical structure of the index of refraction of the atmosphere as a function of such factors as location, season, horizontal distance,

and time. Included also are the results of measurements of the fine detail

variations of refractive index about its mean value at several locations for altitudes up to 20, 000 ft mean sea level. (Met. Abs. 8. 3-345) --Author's

abstract.

E-286 Crysdale, J.H. ; Dickson, F.H.; Egli, J. J. etal. , Large reduction of VHF

transmission loss and fading by presence of a mountain obstacle in beyondline-of-sight paths . Institute of Radio Engineers, N. Y. , Proceedings, 43(5):

627-628, May 1955. 2 figs. , foot -refs. , 3 eqs. DLC --Calculations for the

Mt. Fairweather circuit are revised. The Mt. Fairweather circuit predicts a transmission loss 50 db in excess of the free space transmission loss. Since

smooth earth diffraction theory predicts a loss of 105 db relative to free space,

it follows that the revised theoretical value of the "obstacle gain" is 55 db,

which is 25 db less than the previously predicted value and 18 db less than

the measured value. A number of explanations is given to account for this

discrepancy between theory and experiment. --E.K.

E-287 Davidson, David and Pote, Alfred J. , Designing over horizon communication

links. Electronics, N. Y. , 28(12): 126-131, Dec. 1955. 8 figs. , 4 tables,

17 refs. , 11 eqs. --Long distance, wide band circuits are usable in tropospheric

propagation provided high transmitter power and diversity receiving equipment

are used. Design considerations, including antenna gain and order of diversity,

show how to set up a working system with a given percentage of reliability.

--Authors' abstract.

E-288 Deam, A. P. and Fannin, B. M. , Phase difference variations in 9350 megacycle

radio signals arriving at spaced antennas . Institute of Radio Engineers, Proceedings, 43(10): 1402-1404, Oct. 1955. 4 figs. , ref. DLC -The phase difference

between 9350 megacycle per second radio signals received from a common trans- mitter at two horizontally spaced antennas was measured by the Electrical Engineering Research Lab. of the Univ. of Texas during March 1955. The transmitter

was located on Cheyenne Mountain in Colorado and the site of the receiver was

at Fort Carson, 3. 5 mi distant. The elevation angle of the transmitter as seen

from the receivers was 9°. This paper presents and discusses the results of

these measurements. (Met. Abs. 8 J-78)- -Authors' abstract.

E-289 Eckart, Gottfried, Statistische Beschreibung der dielektrischen Turbulenz in der

Troposphere. Erster teil einer Theorie der Streuung elektrischer Wellen in

Turbul enter Atmosphare. (Statistical presentation of dielectric turbulence in

the troposphere. Pt. 1 of a Theory of the scattering of electric waves in the

turbulent atmosphere. ) Akademie der Wissenschaften, Munich. Math. - Naturwiss. Klasse, Abhandlungen, New Ser. , No. 74, 1955. 34 p. Fig. , 26

refs. , 112 eqs. Pt. 2. Uber die Streuung elektrischer Wellen an Zonen dielektrischer Turbulenz. (Scattering of electric waves at zones of dielectric turbulence.) Ibid., No. 76, 1956. 36 p. 7 refs. , 107 eqs. Pt. 3. Die Analyse
68

der Storunqen der Dielektrizitatskonstanten dielektrisch turbulenter Zonen mittels

Streufelbeobachtungen. (Analysis of disturbances of the dielectric constant of

dielectric turbulent zones by means of observations of the field of scattering.

)

Ibid. , No. 77, 1956. 18 p. 9 refs. , 44 eqs. DWB--Statistical theory of turbulence is developed and presented in detail and applied to the propagation (or

scattering) of ultrahigh frequency waves in the troposphere. The first part of

this series of 3 papers covers in 7 chapters: 1) the definition of dielectric tur- bulence; 2) mathematical definition in form of Fourier series in space and time,

and in the form of a Fourier integral; 3) the variation of the dielectric constant

(DK) in space and time as a random process; 4) the relation between the fre- quency of function of the processes and that of the Fourier coefficients; 5) the

representation of the moments and solution of the moment problem by means of

Mellin (two sided Laplace) transformations; 6) homogeneous stationary spacetime intervals; 7) criteria for introduction of homogeneous stationary intervals

and related problems. Pt. 2 and 3 continue with the theoretical or statistical

treatment and its application to radar scattering or fading, under the assumption

that empirically derived data from attenuation of short waves in a turbulent at- mosphere are not comprehensive enough to give a true picture of the quantitative

effects of turbulent media on the radiation passing through such a medium.

(Met. Abs. 12. 10-135) --M.R.

E-290 Feinstein, Joseph (Bell Telephone Labs. , New Jersey), Information theory

aspects of propagation through time varying media. Journal of Applied Physics,

N. Y. , 26(2): 219-229, Feb. 1955. 3 figs. , table, 45 eqs. DLC -The channel

capacity of a communications system which utilizes wave propagation through a time varying medium such as the ionosphere or troposphere is evaluated in terms

of the statistical properties of the medium and of the noise. The signal fading

in such a system reduces the capacity. Rayleigh fading is found to give rise

to an equivalent signal to noise ratio of . 172, while shallow fading of the Gaussian type augments the noise in the channel by a fraction of the signal power

proportional to the fading depth. An optimum manner of band width subdivision

is shown to exist when selective fading is present. Information theory concepts

are broadened to include the possibility of multiple reception at spaced receiving

sites, and the consequent increase in theoretical channel capacity is computed

as a function of the number of such sites and the signal statistics. The method

of maximum likelihood is utilized to obtain optimum combinatorial laws for the

multiple signals. The commonly employed maximum signal selection diversity

system is shown to perform as well as the optimum system in the presence of

Rayleigh fading, for a small number of receiving sites. (Met. Abs. 14.4-117)

--Author's abstract.

E-291 Florman, Edwin F. , A measurement of the velocity of propagation of very high

frequency radio waves at the surface of the earth. U.S. National Bureau of

Standards, Journal of Research, 54(6): 335-345, June 1955. 12 figs. , 4 tables,

24 refs. , eqs. DLC --The velocity of propagation of electromagnetic waves was

measured at the surface of the earth, using a radio wave interferometer operating at a frequency of 172.8 Mc. The measured phase velocity, converted to velocity in vacuum, or the "free space" value, was found to be 299795 + 31

km/sec. The uncertainty of + 3. 1 km/sec includes a 95% confidence interval

for the mean, plus an estimated limit to the systematic error of + 0. 7 km/sec.

Based on a 50% confidence interval (probable error of the mean), the uncertainty,

including the estimated limit to the systematic error of + 0. 7 km/sec, becomes

+ 1.4 km/sec. The accuracy with which the free space velocity of radio waves

could be measured was limited primarily by the accuracy to which the refractive

index of air could be obtained from measured values of pressure, temperature

and relative humidity. (Met. Abs. 8 J-79) -Author's abstract.
69

E-292 Froome, K. D. , The refractive indices of water vapor, air, oxygen, nitrogen.

and argon at 72 kmc/s. Physical Society of London, Proceedings, Pt. B, 68(11):

833-835, Nov. 1, 1955. 2 figs. , 2 refs. --Cavity resonator measurements at 72 kMc/s compared with those at lower frequency show that nitrogen and argon

did not change all the other components as much as expected from the dipole

theory. --W. N.

E-293 Furutsu, Koichi, Propagation of electromagnetic waves over a flat earth across

a boundary separating different media and coastal refraction. Japan. Radio

Research Laboratories, Tokyo, Journal, 2(7):l-49, Jan. 1955. Figs. , numerous

eqs. Also his: Propagation of electromagnetic waves over a flat earth across two boundaries separating three different media. Ibid. , 2(9):239-279, July 1955.

Figs. , numerous eqs. And his: Propagation of electromagnetic waves over the

spherical earth across boundaries separating different earth media. Ibid. ,2(10):

345-398, Oct. 1955. Figs. , numerous eqs. DBS--This 140 page tripartite

mathematical work is an impressively elaborate treatment of the problems specified in the titles. --G.T.

E-294 Gerks, I.H. , Factors affecting spacing of radio terminals in a UHF link . Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1290-1297, Oct. 1955.

12 figs. , 7 refs. , 18 eqs. DLC —Measurements made by the Central Radio

Propagation Laboratory and others have established the feasibility of producing

UHF fields at long distances which are sufficiently strong and consistent to be

usable for communication purposes. This paper assembles the results of several investigators of the field strength-distance relationship and shows that

these results are in reasonable agreement in a range of about 75 to 250 mi.

Statistical variations from the median due to fading are discussed. Graphical

means are developed to facilitate the determination of the signal-to-noise ratio

at the receiver for various ranges of distance, antenna gain, frequency, trans- mitter power, bandwidth, and receiver noise figure. Diversity systems are explored briefly. Estimates are made of the effect of the medium upon the

antenna gain and the maximum bandwidth. (Met. Abs. 8 J-81)- -Author's abstract.

E-295 Gordon, William E. , Radio scattering in the troposphere. Institute of Radio

Engineers, N. Y. , Proceedings, 43(l):23-28, Jan. 1955. 8 figs. , 11 refs. , 19 eqs. DWB—The theory of radio scattering in the troposphere is modified in

the light of recent observations of the fluctuations in refractive index. The

theory is applied to the communication problem and yields some characteristics

which are peculiar to the scattering mechanism. One characteristic imposes a

limit on the maximum size of an antenna which yields its full theoretical gain.

This characteristic is deduced from the prediction of diversity distance. Height

gain is also deduced from diversity distance. Other characteristics are derived

pertinent to the communication problem, including fading rates and frequency

bandwidth of the scattering mechanism. (Met. Abs. 8 J-82) --Author's abstract.

Gough, M. W. , Some features of VHF tropospheric propagation. Institution of

Electrical Engineers, London, Proceedings, Pt.B, 102(l):43-58, Jan. 1955.

24 figs. , 6 tables, 20 refs. Condensed version in: Institution of Electrical

Engineers, London, Journal, New Series, l(l):34-36, Jan. 1955. 6 figs. DLC--

Widespread v. h. f. continuous signal strength measurements made in tropical

and Mediterranean regions over the last four years have exemplified and thrown

into relief many of the well known mechanisms of tropospheric propagation.

Although these mechanisms are broadly familiar to many engineers and physicists, the practical magnitudes, as exemplified throughout the paper, are
70

perhaps less widely appreciated despite their great importance to the communication engineers. It is the purpose of the paper to present and analyze new

v. h. f. data from the sources indicated, so as to show (a) that observed v. h. f. signal patterns are consistent with tropospheric structures known commonly to occur, and (b) that sufficient information is now available to enable the communication engineer to forecast to a useful accuracy the statistical behavior of

projected v. h. f. radio paths in certain parts of the world. (Met. Abs. 6. 8-147)

--Author's abstract.

E-297 Gudmandsen, P. , Notes on statistical analyses with special reference to the

distribution of fade durations. Akademiet for de Tekniske Videnskaber.

Mikrobolge Laboratoriet, Copenhagen (Report) P 1312/1507/1525, June 24,

1955. 33 diagr. , 4 tables. --Data obtained on sea paths under varying weather

conditions using 3. 2, 6. 4, and 17 cm wavelengths are analyzed and discussed

here. Statistical consideration is given in particular to sampling procedures

employed, found adequate in representing propagation conditions in terms of

distribution of field strengths. Distribution of fade distribution was found very

sensitive to sampling procedure, influence of which is governed by wavelength

employed, perhaps type of path and weather encountered; recording method and

strength, however, seems independent upon length of sampling interval.

(Met. Abs. 8J-84)--From author's abstract.

E-298 Hay, D. R. , Some measurements on VHF and UHF signals at ranges between

50 and 235 miles. Ottawa. Defence Research Telecommunications Establishment. Radio Physics Laboratory, Project Report, 22-0-4, Jan. 6, 1955. 24 p. 10 figs. , tables, 7 refs. -Signal transmissions at 49, 91, 173 and 492 Mc/s

have been recorded for 48 hr periods at ranges of 50, 89, 152, 199 and 234 mi.

These signals were transmitted over rolling terrain between moderately low

antennas. Information has been obtained from these records on the relative

attenuation with distance and the rates of fading of the four frequencies. Records have been made also of thunderstorm signals at these frequencies.

(Met. Abs. 8 J-85) -Author's abstract.

E-299 Hay, D. R. and Langille, R.C., VHF and UHF signals in central Canada. Institute of Radio Engineers, N. Y. , Proceedings, 43(9):1136, Sept. 1955.

2 figs. , 5 refs. DLC--Results of an experiment are presented which was

carried out over several different paths in central Canada. Graph shows a comparison between median measured signals and theoretical signals for diffraction around smooth spherical Earth with atmosphere. Another graph shows

the median of the random component of the signals at range beyond 80 mi.

Examination of the data proves that the signal power varies approximately as

the inverse cubed power of distance from the transmitter. --E. K.

E-300 Heer, O. , Zur tropospharischen Brechunq ultrakurzer Wellen (Taqesqang der

Feldstarke). (Tropospheric refraction of ultrashort waves (diurnal variations

of field strength).) FTZ: Fernmeldetechnische Zeitschrift, Brunswick, 8(3):

129-138, March 1955. 19 figs. , 30 refs. DLC --Following a review of the reasons of tropospheric refraction of ultrashort waves, the microstructure of

the low atmosphere is more precisely studied and the diffraction of rays is

calculated by means of meteorological data. Recordings of a VHF radio line

observed during one year are compared with meteorological observations.

--Author's abstract.
71

Herbstreit, J. W. and Thompson, M.C. (both, Central Radio Propagation Lab. , Nat '1. Bureau of Standards, Boulder, Colo.), Measurements of the phase of

radio waves received over transmission paths with electric lengths varying as

a result of atmospheric turbulence. Institute of Radio Engineers, N. Y. .Pro- ceedings, 43(10): 1391-1401, Oct. 1955. 14 figs. , table, 12 refs. , eqs. DLC--

A system for the measurement of the variations in electrical lengths of radio propagation paths is described. The observed path length instabilities are considered to be caused by the same atmospheric turbulence responsible for the exist- ence of very high frequency and ultra high frequency fields far beyond the radio

horizon. Results obtained on 172.8 Mc and 1046 Mc along 3 1/2, 10, and 60

mi paths are reported. It is pointed out that measurements of this type provide

a powerful tool for the study of the size and intensity of the refractivity variations of the atmosphere giving rise to the observed phenomenon. (Met. Abs.

8 J-86) -Authors' abstract.

Hirao, Kunio and Maruyama, Hiroyuki, Special instruments for observations

and analysis of VHF fading. Japan. Radio Research Laboratories, Tokyo,

Journal, 2(8):207-216, April 1955. 12 figs. , 2 refs. , 5 eqs. DWB--An autocorrelation analysis has been carried out for the examination of fading of VHF

waves. The recording system which is linear in voltage in its recorded fluctuation, and the relay computer for A xy were both designed and constructed

especially for this analysis. A few examples of the results are introduced in

the present paper. The necessary duration of observation and intervals of

reading are also discussed in order to avoid misunderstanding about the statistical quantities of fading. (Met. Abs. 8 J-87)--Authors' abstract.

International Radio Consultative Committee, Atlas of ground wave propagation curves for frequencies between 30 Mc/s and 300 Mc/s (C . C . I . R . Resolution

No. 11). Geneva, Union Internationale des Telecommunications, 1955. XXXV

p. of text. 174 p. of charts. 10 refs. 3 column pages of French, English

(original) and Spanish text. DLC (QC973. 155) -This atlas is composed of 168

main diagrams for direct practical application, plus 24 diagrams featuring typical physical properties. The earth is considered as smooth and spherical,

homogeneous as far as electrical properties are concerned. The troposphere

is stratified, while the gradient of the refractive index near the ground is based

upon 4/3 times the actual value of the effective radius of the earth. --W. N.

Janes, H.B. , An analysis of within-the-hour fading in 100 to 1000 Mc transmissions. U.S. National Bureau of Standards, Journal of Research, 54(4): 231-250,

April 1955. 23 figs. , table, 4 refs. DLC --An analysis is made of the fading

range of 100 to 1000 Mc transmissions received both within and beyond the

radio horizon. The measurements were made during Aug. 1952 over various

Cheyenne Mountain Field Station paths and over the Cedar Rapids, Iowa —

Quincy, 111. path. Fading range is defined as the ratio in decibels of the

signal levels exceeded 10 and 90% of an hour. For each of the four frequencies

studied, the extent to which median fading range and median signal level depend on the angular distance and time of day is shown in the form of graphs and

sample recordings. The data show that beyond the region where diffraction is

considered to be the dominant mechanism, the signal level distributions closely

resemble the Rayleigh distribution in both fading range and general shape.

(Met. Abs. 8J-89)--From author's abstract.
72

E-305 Janes, H.B. and Wells, P.I. (both, Central Radio Propagation Lab. , Nafl.

Bureau of Standards, Boulder, Colo.), Some tropospheric scatter propagation

measurements near the radio horizon. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1336-1340, Oct. 1955. 4 figs. , 7 foot-refs. , 2 eqs. DLC--

Measurements of small variations in 100 Mc field intensity within and just beyond the radio horizon are reported. The measured fields are assumed to be the

resultant of two field components, one having a constant amplitude and the

other being a rapidly fading scattered component. The fading range of the re- sultant field intensity over a 10 minute period is used to determine K. Here,

K is the ratio in decibels of the root -mean-square amplitude of the scattered

component to the amplitude of the constant vector. Curves showing the measured median values of basic transmission loss, fading rate, and K plotted vs hour of the day are included for three of the Cheyenne Mountain transmission

paths. Diurnal variation of these quantities is also discussed. The average

basic transmission loss of the scattered component, Lj^g, can be found if K

and the resultant basic transmission loss, Lfcm, are known. Median values

of Lijas and L]3m are plotted vs the angular path distance,Q Measurement of

the correlation of the resultant field strengths received on two horizontally

spaced antennas within the radio horizon is reported. When the spacing was

varied from 1/2 to 20 wavelengths and the correlation compared to other characteristics of the field, the correlation was found to be as much a function of

Lbas anc* fading rate as it was of antenna spacing. (Met. Abs. 8J-90)

--Authors' abstract.

E-306 Japan. Radio Research Laboratories, Tokyo, Seventh Semi-Annual Meeting on Researches Conducted in the Laboratories. Its Journal, 2(7): 107-109, Jan. 1955.

Listing of papers presented (with English titles). DWB--Lists 16 papers read on

Oct. 26, and 33 on Oct. 27, 1954 on many aspects of ionospheric and tropospheric propagation. Meeting was held at the Hall of the Radio Research Laboratories, Tokyo. (Met. Abs. 8. 3-346)--M. R.

E-307 Jones, R.F. , Abnormal radio propagation Dec. 3. 1954 . Meteorological Magazine, London, 84(997): 225-226, July 1955. DWB--Abnormal propagation on 180.4

Mc/s over 147 mi in England, is discussed. On Dec. 3, 1954, the field strength

was 100 times normal. This is attributed to very dry air as low as 2200 ft with

inversion below. (Met. Abs. 8 J-92)--C. E. P. B.

E-308 Kirby, R.S. ; Dougherty, H.T. and McQuate, P.L., Obstacle gain measurements

over Pikes Peak at 60 to 1046 Mc . Institute of Radio Engineers, N. Y. .Proceedings, 43(10): 1467-1472, Oct. 1955. 11 figs. , 3 tables, 13 refs. , eq. DLC--

Radio transmission loss measurements made over four propagation paths approximately 100 mi in length show the effect of a large mountain obstacle on VHF and

UHF ground-to-ground propagation. Recordings of transmission loss were obtained at four sites as a function of receiving antenna height and by mobile measurements along a route normal to the propagation path. Measurements for propagation directly over Pikes Peak exhibit the well defined lobing associated with

four ray path diffraction theory. Theoretical approximations based on the

FRESNEL-KIRCHHOFF scalar knife edge diffraction theory predicts values of

transmission loss and lobe structures which are in good agreement with those

observed. Measurements for propagation to the east and west of Pikes Peak

are characterized by lower fields at all frequencies and large fading ranges.

(Met. Abs. 8 J-93) -Authors' abstract.
73

Kl inker, L. , Beitraq zum Taqesqanq der Feldstarken im Ultrakurzwellenbereich. (Daily variation of field strength in the ultrashort region. ) Zeitschrift fur Meteorologie, 9(6):178-191, June 1955. 7 figs. , 2 tables, 12 refs. , 13 eqs. MH-BH--

The frequent formation of a nocturnal inversion and its dissipation by day leads

to a diurnal variation of the field strength of ultrashort wave transmissions from

a distance. Ranges up to double can be traced to the changing atmospheric re- fraction. Using measurements of vertical temperature and vapor pressure gradients near the ground this diurnal variation is calculated from the field strength

formula. For mean range over a long period the temperature gradient by itself

gives agreement with observed values. At greater distances, however, there is a discrepancy increasing with distance. The cause is that the importance of re- fraction for ultrashort wave transmission decreases compared with other trans- mission mechanisms due to meteorological causes. Especially the scattering

processes at turbulence elements of the atmosphere should lead to their own

form of the diumal variation. (Met. Abs. 6. 11-233) --Transl. of author's abstract.

Klinker, Ludwig, UKW-Fernempfanqsbeobachtungen: Ihre Bedeutunq fur Meteor- oloqie und Funktechnik. (Ultrashort wave distant reception observations: their

significance for meteorology and radio technology. ) Germany. (Democratic

Republic). Meteorologischer und Hydrologischer Dienst, Abhandlungen, 4, i. e. 5?(35), 1955. 66 p. 36 figs. , 3 tables, 37 refs. DWB-Pt. 1 "The effect of

meteorological conditions upon ultrashort wave propagation over the German

plain and the Baltic" covers a mathematical treatment of the theory of ultrashort

wave propagation including the influence of refraction upon the range of the

ultrashort wave ray, field strength variations beyond the ultrashort wave horizon,

reflections from the free atmospheric inversions and scattering processes at the

turbulence elements of the atmosphere; the apparatus arrangement for making

measurements in specified ultrashort wave ranges in the 3 m band and the evaluation of the propagation measurements; analysis of ultrashort wave propagation

during free inversions with advection; the relationship between nocturnal radiation ground inversion and the daily variation of ultrashort wave propagation over

land, etc. ; The annual variation of ultrashort wave propagation; the influence

of frontal processes, of low pressure areas, lows aloft, unstable stratified cold

air, upon ultrashort wave propagation; large scale weather situations and mean

field strength intensity, etc. Pt. 2 deals with the climatology of ultrashort wave

propagation in Central Europe. It contains statistical data for a land area of

200 sq km and a sea area of 175 sq km, data on temporal field strength intensity

distribution for six ultrashort wave measurement distances 100 to 500 km apart on a basis of five months of observations, decline of field intensity with distance

and daily variation of the ultrashort wave field intensity. (Met. Abs. 8. 3-20)

--I.L.D.

Kono, Tetsuo; Nishikori, Kiyoshi; Fukushima, Madoka; Ikeda, Masao and

Yoshida, Noriaki, Experimental studies on diffracted waves from a mountain

at 3000 Mc/s. Japan. Radio Research Laboratories, Tokyo, Journal, 2(8):

163-180, April 1955. 21 figs. , 4 tables, 8 refs. DWB--Radio transmission

experiments were made at the frequency of 3000 Mc/s over the 243 km path

between Kawaguchi and Ryozen in Sept. and over the 166 km path between

Kawaguchi and Izumi in Dec. 1954. Mt. Yamizo lies in the midway of these

paths. Transmission loss and fading characteristics obtained in this experiment are much different from that of a VHF radio wave experiment over a mountain. In the first experiment, the median value of the field intensity agreed

approximately with that calculated by FRESNEL's knife edge diffraction theory,

but in the second experiment it was about 10 db below the calculated value.

(Met. Abs. 8 J-94) -Authors' abstract.
74

E-312 Kurihara, Yoshitaka (Radio Research Labs. , Tokyo), Trans-horizon microwave

propagation over hilly terrain. Institute of Radio Engineers, N. Y. , Proceedings,

43(10): 1362-1368, Oct. 1955. 13 figs. , 3 tables, 3 foot-refs. , eqs. DLC--

By introducing three path parameters into the geometry of scattered signal transmission, the spherical earth formulas of W.E.GORDON were extended to the

nonspherical earth case. This paper describes the result of analysis. The nonspherical earth formulas were applied to the prediction of the signal power and

characteristics of tropospheric scattered fields on the hilly 93 mi path between

Ithaca and Wethersfield-Springs, N. Y., and on the 119 mi path between Ithaca

and Buffalo, N. Y. The transmission experiments over these two paths were

conducted at Cornell Univ. , at frequencies of 2780 Mc and 9150 Mc. The re- sults of the experiments are presented together with the predictions in this

paper. (Met. Abs. 8 J-95)--Author's abstract.

E-313 LaGrone, A.H. ; Straiton, A. W. and Smith, H. W. , Synthesis of radio signals on over water paths . Institute of Radio Engineers, Transactions, AP-3(2):48-52,

April 1955. 7 figs. , 5 refs. , 20 eqs. DBS--The fluctuations of radio signals

at microwave frequencies on overwater paths are explained on the basis of a periodic rise and fall of the water level. From this study, it is seen that the

variations in the radio signal strength will contain the frequency of the water

level cycles and also the second and third harmonics of the water level cycles.

This same model predicts that the cross correlation function of the fluctuations

of the radio signal at two vertically spaced antennas will drop from unity to zero as the separation distance is changed from zero to one-half of a lobe width of a height gain interference pattern. Although the model assumes reflection from a plane surface, the results of the study successfully explain most of the features

of the observed fluctuations of the radio signals on two overwater paths.

--Authors' abstract.

E-314 Laver, F. J. M. , Introduction to some technical factors affecting point-to-point

radiocommunication systems. Institution of Electrical Engineers, London,

Proceedings, Pt. B, 102(6): 733-743, Nov. 1955. 8 figs. , 100 refs. , 11 eqs.

DLC--An extensive review of literature on point-to-point radio transmission and

factors affecting it. Noise, distortion, attenuation, signal strength, fading,

interference, etc. , are treated in separate sections. Ionospheric and tropospheric propagation factors are considered, for both long and short range, high

and low frequency transmission. (Met. Abs. 8J-96)--M. R.

E-315 Mack, C.L. , Diversity reception in UHF long range communications. Institute

of Radio Engineers, N. Y. , Proceedings, 43(10): 1281-1289, Oct. 1955. 14 figs. , 5 refs. , 20 eqs. DLC --Several diversity techniques employed in UHF beyond

the horizon systems are discussed. Filed experience is evaluated in terms of

equivalent reliability, flexibility and performance. A nonswitching parallel

combiner has become the standard military diversity circuit for UHF long range

receivers. The circuit is described and analyzed. --Author's abstract.

E-316 Mellen, G.L. ; Morrow, W. E. ; Pote, A.I. ; Radford, W.H.and Wiesner, J.B.,

UHF long range communication systems. Institute of Radio Engineers, N. Y. , Proceedings, 43(10):1269-1281, Oct. 1955. 23 figs. , 9 refs. , 25 eqs. DLC--

Recent discoveries about long range propagation of UHF radio waves, together

with careful utilization of high powered transmitters and large antennas, have

made possible reliable multichannel point-to-point radio communication systems
75

which operate over distances of 200 mi or more beyond the horizon. Measurements by various investigators have shown that transmission losses on such

path have median values of the order of 80 db below free space levels. A program of investigation at Lincoln Laboratory, MIT, has yielded detailed propagation data necessary for the design of long distance multichannel UHF radio communication circuits. This also led to the design of specialized equipment for this application. These circuits employ antennas having transmitting and re- ceiving gains of 25-40 db; high power FM transmitters of up to 10 kw output;

sensitive FM receivers having low noise input circuits, and excellent selectivity; and space diversity reception. A procedure for system design is out- lined. --Authors' abstract.

E-317 Muchmore, R.B. and Wheelon, A. D. (both, Guided Missile Research Div. , Ramo-Wooldridge Corp. , L. A. ) , Line-of-sight propagation phenomena, Pt. 1. Ray treatment . Institute of Radio Engineers, N. Y. , Proceedings, 43(10):

1437-1449, Oct. 1955. 9 figs. , numerous refs. , 55 eqs. Pt. 2. Scattered

components. Ibid., p. 1450-1458. 10 figs. , refs., 55 eqs. DLC --The effect

of variations in index of refraction on line-of-sight propagation of electromagnetic waves in the troposphere is investigated using, in Pt. 1, a ray theory

approach. Mean square variations in phase delay and phase correlation between two paths are calculated. It is shown that these quantities are relatively insensitive to the form of space correlation function assumed for the

index of refraction. The mean square phase is proportional to A.N^lo where

lo is scale length and ^N^ the mean square variation in index of refraction,

w_h£jeas__inJ?eyond line-of-sight propagation the received power is proportional

to^N /lo. Variations in angle of arrival are also calculated and it is shown

that here the assumed space correlation of index of refraction is critical in determining the angle of arrival characteristics. It is shown, however, that a certain portion of the angle-of-arrival spectrum is insensitive to the choice.

In Pt. 2 the foregoing investigation of line-of-sight propagation through a tur- bulent atmosphere is continued and enlarged. Generalizations of the ray calculation to include scattering contributions by off axis blobs are given. It is

found that the previous expressions for rms phase errors are substantially

maintained. The dependence of these fluctuations on receiving antenna beamwidth is adduced. These techniques are then applied to estimate phase scintillation for transmission through a rainstorm. Meteorological data are used to relate such errors to rainstorm. Meteorological data are used to relate such

errors to rainfall intensity and infer scintillation frequency spectra. Numerical

values for these effects are given for representative atmospheric conditions.

(Met. Abs. 8. 6-369) -Authors' abstract.

E-318 Northover, Francis H. , Long distance V.H.F. fields. Pt. 1. Partial reflection

from a standard atmosphere . Canadian Journal of Physics, Ottawa, 33(5):241-

256, May 1955. 13 refs. , numerous eqs. Also his: Pt. 2. Refractivity profiles containing " sharp layers "

. Ibid. , 33(6): 316-346, June 1955. Fig. , 2

tables, 13 refs. , numerous eqs. Also his: Pt. 3. The case of two elevated

layers. Ibid. , p. 347-349. Eqs. DWB--Reliable propagation of VHF waves and

microwaves from high power transmitters to distances of several hundred miles

beyond optical range has been demonstrated by an ever increasing number of ex- periments during the last ten years. The fields which have been observed have

consistently been many times greater than the field strengths predicted by the

"effective radius" theory. The present paper will be published in three parts. In Pt. I the theory that the phenomenon can be explained solely in terms of

"partial internal reflection" from elementary layers of a dielectric distribution

where the rate of decrease of ( /<. — 1) with height is everywhere continuous
76

and of the same order of magnitude as in a "standard" atmosphere is carefully

examined and found to be untenable. In Pt.II, the case where the distribution

contains "sharp layers" (i.e., local regions where (/t- 1) changes relatively

rapidly with height) is examined and it is found that these could cause the phen- omenon. However, in view of the other characteristics of the observed field,

it is concluded that the effect in question is probably more usually due to scattering of the electromagnetic waves from atmospheric turbulence. In Pt. 2, the

general solution developed in Pt. 1 is applied to the case in which the refractivity profile contains sharp layers (i. e. local regions where^ and dju- /dh

change very rapidly compared with their rate of variation in a "standard" type

atmosphere). It is found that such layers, when well developed, can cause

distant fields of the order of magnitude of those which have been observed,

but present experimental evidence seems to indicate that scattering from atmospheric turbulence is usually the important factor. An attempt is made to work

out a physical interpretation of the field formation below the elevated layer.

In Pt. 3, the general theory developed in Pt. 1 and in the beginning of Pt. 2 is

applied to derive an equation for the eigenvalues of the propagation for the case of two sharp elevated layers. This equation is very briefly discussed

and some special cases noted. (Met. Abs. 8 J-99)- -Author's abstract.

E-319 Norton, Kenneth A. ; Rice, P.L.; Janes, H. B. and Barsis, A. P. (all, Central

Radio Propagation Lab. , Nat'l. Bureau of Standards, Boulder, Colo.), Rate of

fading in propagation through a turbulent atmosphere. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1341-1353, Oct. 1955. 13 figs. , table, 22

refs. , numerous eqs. DLC --Fading rate is defined to be the number of times

per minute that the envelope of the received field crosses its median level with

a positive slope. This definition of fading rate is equally useful for ionospheric

or tropospheric propagation studies. Furthermore, it may be used with equal

facility on short transmission paths where the ground wave component of the re- ceived field predominates and on the longer transmission paths where the scattered component of the received field predominates. It is shown that this definition of fading rate provides a quantity which is numerically related to the

parameters of the propagation medium under certain conditions which are normally satisfied in either ionospheric or tropospheric propagation studies. The

pertinent parameters of the propagation medium in beyond-the-horizon transmission are the location and shape of the scattering volume and the turbulent and

drift velocities of the scatterers. An extensive discussion is given of the

shape of the tropospheric scattering volume for beyond-the-horizon transmission.

An analysis is then given of some fading rate data obtained in the National

Bureau of Standards tropospheric propagation program in the 92 to 1046 Mc range

of frequencies on transmission paths, 70, 97, 226, and 394 mi in length. Finally, an analysis is given for within-the-horizon propagation. In this case it is advantageous to define fading rate as the number of times per minute that the phase of

the received field crosses its median level with a positive slope. (Met. Abs.

8J-101)--Authors' abstract.

E-320 Norton, K. A. ; Vogler, L.E. ; Mansfield, W. V. and Short, P. J. , The probability distribution of the amplitude of a constant vector plus a Raleigh distributed

vector. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1354- 1361,

Oct. 1955. 4 figs. , 2 tables, 10 refs. , 41 eqs. DLC--The discussion is ac- companied by formulas, tables and graphs. Distribution of: 1) amplitude of a constant vector and of 2) of the Rayleigh distributed vector along with physical requirements involved are treated. The paper ends with a discussion on two

other random vectors as encountered in tropospheric propagation studies. (Met.

Abs. 8J-103)--W. N.
77

-321 Norton, Kenneth A. and Wiesner, Jerome B. , The scatter propagation issue . Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1174-1526, Oct. 1955.

DLC--This large issue of the Proceedings is devoted to about 35 papers on vari- ous aspects of tropospheric or ionospheric propagation of short radio waves beyond the horizon. The introduction by NORTON and WIESNER explains the

phenomenon in terms of two contrasting theories, one that irregular "blobs" in

the troposphere or cosmic dust clouds in the ionosphere are responsible for this anomalous propagation, the other that regular discontinuities could ac- complish the same results (inversions or gradients producing refraction).

(Met. Abs. 8J-100)-M.R.

-322 Norton, K.A. ; Rice, P.L.and Vogler, L.E. (all, Central Radio Propagation

Lab. .National Bureau of Standards, Boulder, Colo.), Use of angular distance

in estimating transmission loss and fading range for propagation through a tur- bulent atmosphere over irregular terrain. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1488-1526, Oct. 1955. 40 figs. , 56 foot-refs. , 71 eqs.

DLC--A discussion is given of the transmission loss expected in free space

with various types of antennas, followed by a description of theoretical prediction curves for the transmission loss expected in tropospheric propagation on overland paths. The Bremmer-van der Pol theory of diffraction and the

Booker-Gordon and Weisskopf-Villars theories of tropospheric forward scatter- ing are then developed in terms of angular distance as a parameter. Angular

distance is the angle in the great circle plane between the radio horizon rays

from the transmitting and receiving antennas. It is shown that this parameter

replaces, to a first order of approximation, both the transmission path length

and the antenna heights. Angular distance is shown to be useful for predicting

the short term within the hour fading range as well as the median transmission

loss. Illustrations are presented of the theoretical dependence of transmission loss on the angular distance, transmission path length, antenna height,

radio frequency, and a parameter AN which is a measure of the vertical gradient of atmospheric refractive index. Most of the long term variations of the

scattered field intensities with time, as well as the climatological variations,

are attributed to changes in AN. A new theory of obstacle gain is developed,

and it is shown that this is particularly useful for explaining some of the un- usually strong fields which have been observed just beyond the horizon in over- land propagation. The diffraction and scattering theories are compared with ex- tensive data on radio transmission loss involving 136, 000 hourly median values

recorded over 122 propagation paths at frequencies between 66 and 1046 megacycles. Estimates of the Booker-Gordon scattering parameter!- CA yi/n ) 2 /lo

and of the Weisskopf-Villars scattering parameter <T (dn/dh)2 J _ [ dn/dh)J| 2

determined from our median radio data and normalized to a height of one kilometer above the surface, are considered to be correlated with the gradient of re- fractivity, AN. The radio data indicate that the magnitude of the scattering cross section decreases in inverse proportion to the radio frequency in the

range we have studied. This provides strong evidence in favor of the Weisskopf-Villars tropospheric forward scattering theory presented elsewhere in

this issue of the Proceedings. Theoretical curves of the average value of the

path antenna gain to be expected in tropospheric forward scatter propagation

are presented as a function of the angular distance, the asymmetry factor, and

the free space gains of the transmitting and receiving antennas. (Met. Abs.

8. 5-340) -Authors' abstract.
78

E-323 Poeverlein, Hermann, Field strength near the skip distance. U.S. Air Force.

Cambridge Research Center, AFCRC-TR -54-104, Jan. 1955. 13 p. 3 figs. , 20 refs. , 26 eqs. DWB (M94 P745f)--The field strength in an interval of a few

hundred km beyond the skip distance is derived from theoretic-optical considerations as proportional to (X - Xs + A Xq) where X - Xs is the distance from

the skip distance. The small correction term ^Xc provides the correct skip

distance value of the field strength. The focusing which occurs at the skip

distance itself increases the field strength under certain regular conditions to about eight times the unfocused free propagation field strength. At short skip

distances, however, this focusing becomes weaker and another much broader

field strength maximum appears at a distance from the transmitter approximately

proportional to the layer thickness. (Met. Abs. 8 J- 104) --Author's abstract.

i/ E-324 Prokott, Ernst, Ubertraqungsversuche bei 530 MHz mit Reichweiten ienseits

der optischen Sicht. (Transmission tests at 530 Mc/s at ranges beyond the

optical horizon. ) FTZ: Fernmeldetechnische Zeitschrift, Brunswick, 8(8):430-

437, Aug. 1955. 18 figs. , 2 tables, 2 eqs. DLC --Propagation tests were

performed over two radio lines in central Germany on 533. 5 Mc/s. The aim

of these experiments was to find out the required amount of technical experiments for satisfactory communication. --Author's abstract.

E-325 Roessler, E. , Erklarungen fur die bestandiqen Feldstarken unter 10 m. Wellenlanqe weit hinter dem Horizont . (Explanation of the prevailing field strengths

below 10 m wavelengths far beyond the horizon.) Elektronische Rundschau,

9(4): 151-155, 1955. 4 figs. , 56 refs. --This is a concise survey of various

theories and works on beyond-the-horizon propagation originating in the USA,

United Kingdom and Germany. --W. N.

E-326 Rogers, T. F. , VHF field strength far beyond the radio horizon. Institute of

Radio Engineers, N. Y. , Proceedings, 43(5):623, May 1955. Fig. DLC--Brief

report on experimental transmission of 1.4 m waves over a 420 statute mile

flight path over the North Atlantic Ocean eastward from Boston, Mass. It is

shown that 1.4 m field strength decreases less rapidly than MEGAW's observations with 10 cm waves. This may indicate a dependency upon wavelengths

so far as attenuation is concerned, however, with the reservation that weather

conditions and seasons differed in these transmissions. (Met. Abs. 8J-105)

--W. N.

E-327 Sacco, Luigi, II colleqamento radio in regime di superrifrazione atmosferica.

(Radio link during atmospheric superrefraction. ) Alta Frequenza, Milan, 24(6):

436-469, Dec. 1955. 10 figs. , refs. , numerous eqs. DLC --Meteorological re- search conducted in Italy during the last few years has shown that superrefraction at heights below 500 m occurs with some frequency, both during the day

and at night. In this article the geometrical parameters (reflection point, path

and angle of incidence of reflected waves, convergence coefficient) of radio

links during such conditions are studied, values of these parameters are determined and their application to calculation of the received field is shown.

The formation of tropospheric ducts is not considered, but possibilities of focusing and reflection are discussed. --Transl. of author's abstract.
79

Saxton, J. A. and Lane, J. A. , VHF and UHF reception effects of trees and other

obstacles. Wireless World, London, 61(5) -.229-232, May 1955. 3 figs. . 4 refs.,

2 eqs. DLC--Some experiments to determine the attenuation caused by screens

of trees and thick woods at frequencies of 100, 540 and 1200 Mc/s are described,

and these and other data are used to estimate the attenuation over the frequency

range 30 - 3000 Mc/s. This work was carried out as part of the program of the

Radio Research Board. The nature of the diffraction loss and variation of field

strength behind opaque obstacles of various kinds for the same frequency band

is examined on the basis of the Fresnel theory of diffraction. --Authors' abstract.

Silleni, Stelio, Su alcuni fattori qeofisici nelle radiocommunicazioni. (Some

geophysical facts in radiocommunication. ) Annali di Geofisica, Rome, 8(1):

135-148, Jan. 1955. 4 figs. , 14 refs. , eqs. Italian and English summaries

p. 146-147. DLC--A review of ionospheric and tropospheric propagation theory

and the latest empirical data on effects of time of day, temperature, humidity

and magnetic disturbances which affect radio propagation in the various wave

bands (including short wave radio telephone circuits). (Met. Abs. 8J-106)

--M.R.

E-330 Silverman, Richard A. (N. Y.Univ.), Some remarks on scattering from eddies.

Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1253-1254, Oct. 1955.

8 foot-refs. , 2 eqs. DLC--The Gaussian character of electromagnetic radiation

scattered from turbulent atmosphere fluctuations is shown to follow from the

Central Limit Theorem, even when the scattering is from only one macro-eddy

and there is coupling between eddy motions of different sizes. It is suggested

that including the effects of eddy coupling may increase the calculated average

scattered power enough to give agreement with experiment. (Met. Abs. 8J-107)

—Author's abstract.

E-331 Simon, J.C., Quelques problemes de fluctuations en radioelectricite. (Some

radioelectric fluctuation problems.) Annales de Radioelectricite, Paris, 10(39):

3-19, Jan. 1955. 9 figs. , 10 refs. , 49 eqs. DLC--The statistical approach

enables simple solutions to be given to a great number of problems in the field

of radioelectricity. Many of these are related to the study of the sum of vectors, the phase angles of which are random. This study is undertaken in a

first theoretical part. The correlation function concept applied to this problem

is studied in detail. The second part gives different practical applications

such as multiple reflections on a transmission line, propagation problems,

influence of scattered echoes, radiation of a great number of sources, fluctuations of a radar echo, and effect of phase error on antenna performance.

—Author's abstract.

E-332 Smith-Rose, R.L. , Radio communication by wave scattering. Wireless Engineers, 32(11): 287-290, Nov. 1955. -Tropospheric and ionospheric works are discussed briefly, including experiments in the United Kingdom. --W. N.

E-333 Smith-Rose, R. L. and Saxton, J. A. , UHF television broadcasting: study of

propagation conditions: geographical separation of stations using common

freguencies . Wireless World, London, 61(7):343-346, July 1955. 2 figs. , 2 tables, 13 refs. DLC --Possibilities of the ultra high frequencies (UHF) for

broadcasting purposes with special reference to television transmission in
80

Bands IV and V (470 to 585 and 610 to 960 Mc/s respectively), are considered.

It is already appreciated that a single UHF transmitter cannot serve as large an

area as a radio or television transmitter in the VHF bands. The discussion includes a comparison of the relative usefulness of UHF and VHF for television

transmissions. --E. K.

E-334 Stack-Forsyth, E. F. , An experimental study of the propagation of 10 cm radio

waves over a short non-optical sea path. Institution of Electrical Engineers,

London, Proceedings, Sec.B, 102(2) :231-236, March 1955. 8 figs. , table,

5 refs. , 5 eqs. DWB--Tests of 10 cm radio propagation over sea paths up to 21. 1 mi (1. 14 times optical horizon) were made near Durban in April-Aug. 1953.

Temperature and humidity up to 600 ft were obtained by balloon or kite. A duct

of average depth 120 ft was present for a large proportion of the time, especially

night and early morning with a secondary maximum at midday; it was caused by

a high lapse of vapor pressure. (Met. Abs. 8 J-108)--C. E. P. B.

E-335 Staras, Harold (Engineering Products Div. , RCA, Camden, N. J. ), Forward scattering of radio waves by anisotropic turbulence . Institute of Radio Engineers,

N. Y. , Proceedings, 43(10): 1374-1380, Oct. 1955. 12 figs. , 9 foot -refs. , numerous eqs. DLC--This paper extends the theory of tropospheric scatter by deriving the appropriate formulas for the important radio system parameters under the

assumption that the turbulence is anisotropic, i. e. , that the scale of turbulence

in the horizontal dimension is different from the scale of turbulence in the vertical dimension. The frequency dependence of the scattered radiation is the same

for anisotropic large-scale turbulence as for isotropic. Furthermore, those radio

systems parameters which depend only on the rate of decrease of scattered

energy with elevation angle (such as the vertical correlation function and height

gain) remain unchanged under the assumption of anisotropy while those parameters which depend on the energy coming out of the great circle plane (such as

the horizontal correlation function) can be influenced quite substantially by

anisotropy. Several other parameters such as the longitudinal correlation function, bandwidth of the medium and effective antenna gain may also be influenced

by anisotropy but generally to a lesser extent. A comparison is made between

our theory and some recent NBS data -- indicating that anisotropy does exist.

(Met. Abs. 8 J- 109) -Author's abstract.

E-336 Tao, Kazuhiko, On the relationship between the hourly variation of field

strength and the structure of the lower atmosphere. Japan. Radio Research

Laboratories, Tokyo, Journal, 2(8):181-191, April 1955. 13 figs. , table, 10 refs.

DWB--It is clear that the relationship between the hourly variation of field

strength and the distribution of the refractive index in the lower atmosphere is

ascertained by the actual data from captive balloon observations, i. e. , the high

level of field strength corresponds to the abnormal distribution of the refractive

index. Moreover, it is clear that the abnormal distribution of the refractive

index can be explained from the viewpoint of synoptic meteorology. (Met. Abs.

8 J- 110) -Author's abstract.

E-337 Texas. Univ. Electrical Engineering Research Lab. , Bibliography of Reports.

Memoranda. Technical Publications, Papers and Theses. 1945-1955. Contract

Nonr 375(01), Report No. 75, March 31, 1955. 45 p. --The material is arranged as follows: (1) Reports to the sponsoring agencies: U.S. Navy, U.S. Air Force,

U.S. Army, U. S. Nat. Bur. of Standards, and industrial organizations; (2) Technical publications; (3) Papers by staff members of the University and (4) theses.

(See ref. E-1083). (Met. Abs. 8 J-11D--W. N.
81

Tidd, W. H. (Bell Telephone Labs. , N. Y.), Demonstration of bandwidth capabilities of beyond horizon tropospheric radio propagation. Institute of Radio

Engineers, N. Y. , Proceedings, 43(10): 1297-1299, Oct. 1955. 8 figs. (incl.

photos). DLC --Tropospheric radio transmission beyond the horizon is characterized by rapid and selective fading, which suggests a possible limitation on

the useful bandwidth. The tests discussed were made to explore the bandwidth

capabilities of this medium. Bell Telephone Laboratories conducted these tests

in cooperation with the M.I.T. Lincoln Laboratory on a 188 mi path at 5050 Mc

with a power of 300w and 28 ft paraboloidal antennas. Two types of tests were made. First a 12 voice channel multiplex system for intermodulation crosstalk.

IF band was 1. 3 Mc. Then television tests were made with a deviation of + 4

Mc and IF bandwidth of 30 Mc. No significant impairment in system quality

could be attributed to distortion in transmission medium in either test. (Met.

Abs. 8. 5-342) -Author's abstract.

Tohsha, M. , On the superrefraction of microwave in Kanto District. Journal of

Meteorological Research, Tokyo, 7(7):446-454, Oct. 1955. 12 figs. , 3 tables,

8 refs. , 7 eqs. In Japanese; English summary p. 446. DWB--Radar echoes

accompanying superrefraction which is anomalous propagation of radar wave

were observed before sunset on Aug. 5, 1954 in Kanto district. Whether the

phenomenon depends on the K type refraction in which the effective radius of

the earth increases, or on the duct type in which the distribution of refractive

index N or M decreases with height in the surface layer of the atmosphere, is

discussed. From the judgment of observational data at Tateno and Tsukuba,

it is found that K type anomalous propagation had not occurred. It is considered that the phenomenon of superrefraction occurred as the duct type, from the

minute analysis of aerological sounding at Tateno. Also, the formation of duct

was discussed synoptically, using the data observed in the networks of meteorological stations in Kanto district, and the condition that the two air flows were mixed in the surface layer was found to be necessary for the formation.

The 4000 Mc receiving and its recording of one way transmission between

Mitaka and Tsukuba were operated by the Electric Communication Laboratory,

and the attenuation of duct layer was observed in the period of the anomalous

echoes, the value of which attained to about 10 db. On the other hand, a condition that air flows were not mixed was investigated, in which case such superrefraction as the above mentioned was not found. (Met. Abs. 8 J-113) --Author's

abstract.

Trolese, L. G. (Smythe Res. Associates, S. Diego, Calif. ), Characteristics of

tropospheric scattered fields . Institute of Radio Engineers, N. Y. , Proceedings,

43(10): 1300-1305, Oct. 1955. 12 figs. , table, 6 refs. , eqs. DLC -Experimental results obtained with transmissions at wavelengths of 3. 2, 9. 3 and 24 cms

over a 46. 3 mi path are presented. With low terminal heights the scattered field

was dominant on this path. Tests with a narrow beam antenna indicate that the

scattered field arrives at the receiver spread over an appreciable angle. This

angle is some five to seven times as large as the Booker-Gordon theory predicts on the assumption that the scale of turbulence is large compared to the wavelength. Loss in ability to receive power in proportion to antenna gain was en- countered for antennas with aperture diameters greater than about 20 wavelengths.

This loss occurs for aperture sizes considerably smaller than the Booker-Gordon

theory predicts. The speed of fading of the scattered field signal increases

almost linearly with frequency. This agrees fairly well with the concept (due to Ratcliffe and applied to tropospheric scattering by Booker and Gordon) that fading is due to beating between various scattered field components whose
82

frequencies differ by a fractional Doppler shift due to motion of the scatterers.

The speed of fading always increases, during the day, with time of day and

does not correlate with mean upper wind speed. This increase with time of

day is probably connected with the repetitive diurnal meteorological cycle

prevalent in Arizona. (Met. Abs. 8. 3-349) --Author's abstract.

E-341 U.S. Office of Naval Operations, U.S. Navy Marine Climatic Atlas of the World . Vol. 1. North Atlantic Ocean. Its NAVAER 50-1C-528, Nov. 1, 1955. xvii p. 275 charts (in color), 31 refs. Vol. 2. North Pacific Ocean. Ibid. , 50-1C-529,

July 1, 1956. xvii p. 275 charts (in color), both 50 X 34 cm. DWB (M82. 3

U585m)--Each of these carefully compiled atlases contains among many other

charts useful for naval air and sea operations, four charts covering the "Modified Refractive Index" or "B" Index for the respective seasons (Dec. -Mar. to Sept. -Nov.). The data are presented in frequency distribution paste-ups for

the 60 or more upper air stations in all parts of the Atlantic or Pacific (including Weather Ships). The values presented are for 25% and 75% of all B Values

(quartets) for each of 5 levels (surface, 950, 900, 850 and 800 mb). The data

are derived from 0300Z observation for varying lengths of record (1946-1955).

Charts of frequency of inversions and of annual temperature and humidity are also included. (Met. Abs. 8J-116)--M.R.

E-342 Villars, F. and Weisskopf, V.F. , On the scattering of radio waves by turbulent

fluctuations of the atmosphere. Institute of Radio Engineers, N. Y. , Proceedings,

43(10): 1232-1239, Oct. 1955. 5 figs. , 2 tables, 20 refs. , numerous eqs. DLC--

This paper presents a theoretical analysis of the mechanism that enables transmission of VHF signals over distances of the order of 10^ km. It is found that

turbulent mixing, operating at the lower edge of the E layer (h = 80-90 km) produces fluctuations in electron density of sufficient intensity to account for the

observed signals. The basic assumptions are the existence of a sufficiently

strong gradient of electron density (dN/dh 10^ cm'^/km) and a reasonable

level of turbulent activity. (Met. Abs. 8 J- 117) -Authors' abstract.

E-343 Waterman, Alan T. , Jr. , Radio power received via tropospheric scattering. Stanford Univ. Applied Electronics Laboratory, Contract DA 36-039-Sc -63189,

Contract Nonr 225(10), Technical Report, No. 461-1, July 18, 1955. 7 p. 9 refs.,

eqs. (U.S. ASTIA, AD 66502)--UHF and SHF beyond horizon propagation as a function of atmospheric turbulence is treated theoretically here. Integration of

the scattered power involved can be performed exactly as is demonstrated.

(Met. Abs. 8J-118)-W. N.

E-344 Muchmore, R.B. and Wheelon, A. D. , Line-of-sight propagation phenomena--! . Ray treatment . Institute of Radio Engineers, N. Y. , Proceedings, 43(10):1437-

1449, Oct. 1955. 9 figs. , 22 refs. , 55 eqs. Also, Wheelon, A. D. and Muchmore, R.B. , Line-of-sight propagation phenomena--!!. Scattered com, onents . Ibid., 43(10): 1450-1458, Oct. 1955. 10 figs. , table, 19 refs. , 55 eqs. Also:

Wheelon, A. D. , Near-field corrections to line-of-sight propagation. Ibid. , 43(10): 1459-1466, Oct. 1955. 3 figs. , 9 refs. , 53 eqs. DLC-In Pt. 1, the

effect of variations in index of refraction on line-of-sight propagation of electromagnetic waves in the troposphere is investigated using a ray theory approach. Mean square variations in phase delay and phase correlation between

two paths are calculated. It is shown that these quantities are relatively insensitive to the form of space correlation function assumed for the index of

refraction. The mean square phase is proportional toAN2

, where lo is scale
83

length and AN^ the mean square variation in index of refraction, whereas in

beyond line-of-sight propagation the received power is proportional to AN^// . Variations in angle of arrival are also calculated and it is shown that here the

assumed space correlation of index of refraction is critical in determining the

angle of arrival characteristics. It is shown, however, that a certain portion

of the angle-of-arrival spectrum is insensitive to the choice. In Pt.2, the foregoing investigation of line-of-sight propagation through a turbulent atmosphere

is continued and enlarged. Generalizations of the ray calculation to include

scattering contributions by off-axis blobs are given. It is found that the previ- ous expressions for tms phase errors are substantially maintained. The depend- ence of these fluctuations on receiving antenna beamwidth is reduced. These

techniques are then applied to estimate phase scintillation for transmission

through a rainstorm. Meteorological data are used to relate such errors to rainfall intensity and to infer scintillation frequency spectra. Numerical values

for these effects are given for representative atmospheric conditions. In the

last article, the line-of-sight propagation of electromagnetic waves in a turbulent medium is considered. The field equation describing propagation through

a region characterized by random dielectric fluctuations is first developed.

Solutions of this equation which represents the scattered field are derived with

ordinary perturbation theory. These solutions are next used to calculate the rms phase error for an arbitrary path in the troposphere. This approach includes

both a three dimensional and near field description for the multipath, scattered

amplitudes; thereby overcoming the limitations of previous treatments. The

phase correlation between signals received on two parallel transmission paths

is derived last to illustrate the role of overlapping antennae beams. (Met.

Abs. 8J-98)--From authors' abstract.

Wheelon, A. D. (Ramo-Wooldridge Corp. , Los Angeles, Calif. ), Note on scatter

propagation with a modified exponential correlation. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1381-1383, Oct. 1955. 14 refs. , numerous

eqs. DLC--A phenomenological exponential space correlation of dielectric fluctuations is normally used to predict scatter field strengths beyond the horizon.

This paper introduces a modified exponential model which includes effects of

the smallest blob cutoff in the turbulent spectrum and rectifies the correlation's

cusp at the origin. It is found that the present agreement of troposphere scatter

experiments with the exponential function does not depend on this cusp. It is

suggested that frequency dependent tropospheric fields recently measured below

25 cm may indicate the influence of the correlation's fine structure. The same

model is then applied to the ionosphere, where the extended range VHF scatter

wavelengths just straddle the smallest blob size (~3m) in the E layer. The

turbulence fine structure is most important for this propagation and gives a qualitative explanation of the curious dualism in frequency scaling laws observed at opposite ends of the VHF band. Satisfactory variation of signal strength with

scattering angle is also predicted by this model. It is shown that scatter measurements can provide valuable estimates of the atmosphere's fine structure at various heights. (Met. Abs. 8. 5-344) -Author's abstract.

Yamada, Ryozo, On the radio wave propagation in a stratified atmosphere.

Physical Society of Japan, Journal, 10(l):71-77, Jan. 1955. Table, 6 figs. , 7

refs. , numerous eqs. DWB--In the present paper certain approximate methods

concerning operators H of Hilbert space which can be expressed in the form

H = T * T are developed. Some theorems are formulated with remarks and ex- amples. They give a method of obtaining upper and lower bounds of the value

of the solution, at each preassigned point, of a boundary value problem. As

a numerical example we consider the following Poisson equation A u = 1 in D,
84

u = on C, where D denotes the square domain in the xy plane with vertices at

(1, - 1), (1, 1), (-1, 1), (-1, -1) and C is the boundary of this square. Upper

and lower bounds of the value of the solution u at the origin are calculated. The

result of the second approximation is 0. 2939 f£ u(0. 0) *s 0. 2953. In order to show that the results are applicable to many problems, several differential operators familiar in mathematical physics, for instance, Laplace's differential operators with different boundary conditions are reduced to the form T* T. (Met.

Abs. 8 J-120) -Author's abstract.

1956

E-347 Abild, B. , UKW-Feldstarke als meteorologisches Element. (USW field strength as a meteorological element.) Fernmelde -Praxis, 33(1/2) :25-32, Jan. 1956.

(Unchecked) —From the well established functional correlation between weather

and field strength is it not merely possible to derive the origin of the field

strength fluctuation, but also to determine the state of the atmospheric layers

from the characteristics of field strength? Field strength recordings will complement the random tests conducted by way of radiosonde ascents, thus constituting an integral of the weather in time and space, particularly distinct when

fronts cross the path under measurements. Uniquely determined results of simultaneous observations over several lengths of paths are thus obtainable. Individual examples of weather analysis by means of field strength characteristics of

the logs Schleswig-Hamburg and Schleswig-Hannover (117 and 242 km, 88. 5 and

97. 8 Mc respectively) are given. It is concluded that a network of meter waves

will provide a detailed picture of humidity and other conditions in the lower

layers of the atmosphere over a large region. --N. T. G.

E-348 Altman, Frederick J. (Int. Teleph. & Telegraph Corp. ), Configurations for

beyond-the-horizon diversity systems. Electrical Communication, N. Y. , 33(2):

161-164, June 1956. 2 figs. , 3 foot-refs. DLC--The recent application of the

dual polarization method of exciting antennas to beyond-the-horizon systems

has provided a hitherto unexplored parameter to provide many configurations as

yet unused. A systematic classification and nomenclature is described, and

26 systems, including those already well known, are derived from the elementary forms shown. (Met. Abs. 14. 5-127)--From author's text.

E-349 Altman, F.J. (Int. Teleph. & Telegraph Corp. ), Design chart for tropospheric

beyond-the-horizon propagation . Electrical Communication, N. Y. , 33(2):165-

167, June 1956. Fig. , table. --This chart represents a summary of propagation

data presently available and facilitates choice of equipment and the computation

of carrier-to-noise ratio. The practical applicability of the curves is demonstrated by three sample computations tabulated. (Met. Abs. 14. 7-101) --W. N.

E-350 Altman, F. J. ; Gray, Richard K. ; Kandoian, Armig G. and Sichak, William

(all, Int. Tel. & Tel. Corp. ), 900 megacycle pulse-time-modulation beyond the

horizon radio link. Electrical Communication, N. Y. , 33(2): 143-150, June 1956.

12 figs. (incl. photos). --Some results obtained with pulse-time equipment for the

study of this propagation to multi channel transmissions, are discussed. The

experiments are conducted over a 2 way link, Nutley, N.J. -Southampton, Long

Island, N. Y. It is concluded that pulse-time-modulation (ptm) retains its known

properties when applied to trans-horizontal propagation. The ptm equipment

used is described and illustrated. (Met. Abs. 14. 4-126) --W. N.
85

E-351 Altman, F. J. and Sichak, Wm. (both, Int. Teleph. & Telegraph Corp. ), Simplified diversity communication system for beyond-the-horizon links. Electrical

Communication, N. Y. , 33(2): 151-160, June 1956. 15 figs. , photo, 2 foot-refs.,

eqs. --The 900 Mc nonoptical path transmission experiments as conducted between Nutley, N.J. and Southampton, Long Island, N. Y. , by means of frequency

modulation, frequency division multiplex, and diversity reception is reported on

here. Since the emphasis is on equipment economics and the analysis of diversity combining methods, the system is described in detail. (Met. Abs. 14.5-128)

-W. N.

E-352 Ament, W. S. , Forward and back scattering from certain rough surfaces.

IRE Transactions on Antennas and Propagation, N. Y. , 4(3):369-373, July 1956.

3 figs. , 3 refs. , 12 eqs. DLC- -Heuristic relations are derived between the

specular reflection coefficient, R, and the radar echoing power of rough sur- faces in which induced current elements are constrained to radiate equal powers

in the reflected ray's direction and back toward the radar. To the extent that

currents in the surface and fields scattered by it are calculable through a self

consistent formulation, a simple Fresnel zone computation of R shows that O~ , the radar area per unit area of mean plane, is proportional to /R2/sin2 & , where

& is the angle incident rays make with the mean plane. It is plausibly assumed

that large scatterers on the surface cast shadows with beamwidth proportional to radar wavelength A ; here the argument leads to cro & ( /R2/ s in2 0/\ . In two

appendices the law cf = 4 sin2 9 is derived for a lossless surface obeying

Lambert's law, and a known self consistent solution of a rough surface problem is examined by three generally applicable criteria. --Author's abstract.

E-353 Ames, Leon A. ; Martin, Edward J. and Rogers, Thomas F. , Long distance

VHF - UHF tropospheric field strength and certain of their implications for; radio

communications. IRE, Transactions on Communications Systems, N. Y. , CS-4

(1): 102-103, March 1956. 2 figs. DBS-Data available from long path length

measurements have been subjected to analysis and comparison. As a result, it appears that a good estimate of temporate latitude transmission loss can now be

made within the 100-500 Mcps region to distances of 400 mi, and usable estimates to 600 mi. --From authors' abstract.

E-354 Barsis, A. P., Some aspects of tropospheric radio wave propagation. IRE trans- actions on Broadcast Transmission Systems, N. Y. , PGBTS-6-.1-10, Oct. 1956.

10 figs. , table, 13 refs. DBS--The Tropospheric Propagation Research Section

of the Radio Propagation Engineering Division, National Bureau of Standards,

has conducted extensive measurements of programs in the 100-1000 Mc fre- quency range. A variety of transmitting and receiving antenna heights was used,

and long term recordings are available over distances ranging from well within

to far beyond the radio horizon. Some results of this measurement program are evaluated to provide estimates for power requirements and interference problems

concerning broadcasting services in this frequency range. --Author's abstract.

E-355 Barsis, A. P. and MacGavin, R.E. , Report on comparative 100 Mc measure- ments for three transmitting antenna heights. IRE Transactions on Antennas

and Propagation, N. Y. , 4(2):168-174, April 1956. 17 figs. , 6 tables, 7 refs.

DBS --This report evaluates measurements taken during Aug. 1952 at a frequency

of 100 Mc as transmitted from three transmitting sites at elevations ranging from
86

6220 ft to 14, 110 ft above msl. Six receiving sites were used, ranging in distance

from approximately 50 mi to 620 mi from the transmitter sites. Results are presented in terms of hourly medians of recorded field intensity and their distributions, as well as the over-all median values and deviations derived from these distributions. (Met. Abs. 8 J-121) -Authors' abstract.

E-356 Bean, B. R. , Some meteorological effects on scattered radio waves. Institute of

Radio Engineers, IRE Transactions on Communications Systems, N. Y. ,CS-4(1):

32-38, March 1956. 12 figs. , 9 refs. , 4 eqs. DLC--The long term variations of

received scattered fields due to atmospheric effects are estimated for frequencies

of 100 to 50, 000 Mc and over propagation paths of 100 to 1000 mi. The long term

variations are presented in two parts: (1) empirically derived variations excluding

absorption and (2) theoretically derived variations due to gaseous atmospheric

absorption. The absorption effects are obtained by following a scattered radio

wave through an actual atmosphere. (Met. Abs. 8 J-178)--Author's abstract.

E-357 Beard, C.I. ; Katz, Land Spetner, L. M. , Phenomenoloqical vector model of

microwave reflections from the ocean. IRE Transactions on Antennas and Propagation, N. Y. , 4(4):162-167, April 1956. 4 figs. , 2 tables, 15 refs. , eqs. DLC--

The model is based on experimental data and fills a gap in the study of microwave

reflection from water surfaces. --W. N.

E-358 Bolljahn, J. T. and Lucke, W. S. , Some relationships between total scattered

power and the scattered field in the shadow zone. IRE Transactions on Antennas

and Propagation, N. Y. , 4(1):69-71, Jan. 1956. Fig., 19 eqs. -Equations are derived which relate the far-zone scattered field, as measured in the shadow zone

of an electromagnetic scatterer, to the total energy scattered and absorbed by the

scatterer, the energy stored in the fields about the scatterer is also related to the

far-zone scattered field in the shadow zone. --Authors' abstract.

E-359 Carl, Helmut (C.Lorenz A. G. , Stuttgart), Range of multichannel radio links

between 30 and 10. 000 megacycles. Electrical Communication, N. Y. , 33(2):

168-173, June 1956. 8 figs. (incl. photo), 5 foot -refs. --This paper was published

in SEG-Nachrichten, 3(4): 185-187, 1955 and is the English version of the original

title: "Die Grenzen der Reichweite von Richtfunkstrecken fur Vielkanalubertragung im Freguenzgebiet von 30-10,000 MHz". It reviews the 10 yr evolution of

communication from 30 to 10,000 Mc. It is concluded that the optical and the

transhorizontal will continue to supplement one another for some time. --W. N.

E-360 Carr, T. R. , Tropospheric propagation study progress report for 1955: counter- measures program. U.S. Naval Air Missile Test Center, Point Mugu, Calif. , Technical Memorandum Report, No. 102, July 1, 1956. 21 p. 25 p. of charts

(33). 11 figs. , 18 refs. Also: Carr, T.R.and Appel, John, Tropospheric

propagation study progress report for 1956. Ibid. , No. 106, May 1, 1957. 95 p. 95 figs. (incl. photos), 12 refs. , eqs. DWB (M(055) U5842uni) -Strong refractive

index gradients associated with temperature inversions along the Southern Calif,

coast result in radio holes and ducts that interfere with missile tests at the Naval

Air Missile Test Center (Point Mugu, Calif. ). Two airborne microwave refractometers from the University of Texas were used in 1955 and 1956 to obtain refractive index profiles over the sea and these were compared with profiles calculated
87

from radiosonde data at shore stations. Anomalous propagation data uses, ter- rain, meteorology of area, instrumentation, sounding procedures, methods of calculating and comments on individual soundings, plus a large number of the soundings made in Jan. 1955 - Dec. 1956 are described, illustrated or presented in

graphical form in these reports. Flight paths are also shown. (Met. Abs.

12.3-102)--M.R.

E-361 Carroll, Thomas J. (M. I. T.Lincoln Lab. .Lexington), Marconi's last paper "On

the propagation of microwaves over considerable distances". Institute of Radio

Engineers, N. Y. , Proceedings, 44(8): 1056-1057, Aug. 1956. DLC. Includes

translation by R.M.Fans into English of the original Italian: Marconi, G. , Sulla

propagazione di micro-onde a notevole distanza (originally published 1933, and

included in the Scritti di Guglielmo Marconi, pub. Rome 1941. --The two important

last papers published by Marconi in 1932 and 1933 did not attract much attention

in the scientific world, but now it is evident that the great inventor was well

ahead of his time in this respect, just as he was regarding trans-Atlantic propagation of long radio waves. A translation of the 13 sentence paper, which was published in 1933, reveals that MARCONI did not believe high frequency radio waves

were limited to the optical horizon, and that results of tests made from Santa

Margherita Ligure and a receiver on a yacht (Elettra) along the coast of Tirreno

(Aug. 2-6, 1933) at 60 cm (500 mc) indicated that good reception was to be had at 150 km, or 5 times the distance to the optical horizon. The year before (July and

Aug. 1932) he had obtained poorer reception — only twice the optical distance.

Signals could be detected at 258 km or 8 times the optical distance, and across

high hills to boot. The author intended to publish more complete results, but his

health was poor and he died soon after (1937). (Met. Abs. 8J-123)--M. R.

E-362 Chisholm, James H. (M. I.T.Lincoln Lab. ), Progress of tropospheric propagation

research related to communications beyond the horizon. IRE Transactions on Communications Systems, 4(1):6-16, March 1956. 14 figs. , 12 refs. -The simplified

presentation of theoretical models and discussion of selected experimental results

given in this paper is intended to convey a general picture of tropospheric scattering. The results of experimental measurements show that reliable communications

with useful bandwidths can be obtained at UHF and SHF over paths 150 to 300 mi

in length, utilizing radio waves of several kw, scattered by the troposphere.

Angular measurements of pulse signals indicate that the mechanism of scattering

is highly directive and that multipath delays are less serious than originally anticipated. —Author's abstract.

E-363 Chu, CM. and Churchill, S. W. , Multiple scattering bv randomly distributed

obstacles - Methods of solution. IRE Transactions on Antennas and Propagation,

N. Y. , 4(2):142-148, April 1956. 2 figs. , 13 refs. --Known methods are reviewed

generally. Multiple scattering is considered from the Lagrangian and the Eulerian

viewpoints. Solution for several geometries by way of representing the intensity

of components is shown. More accurate results than those obtained by way of

the diffusion theory for anisotropic scattering are those yielded by the two-flux

model developed. A six-flux model will increase accuracy but requires machine

computations. --W. N.
88

E-364 Clara, Jose Maria (Nat'l. Telephone Co. of Spain) and Antinori, Albino (Ministry

of Post Office and Telecommunications, Rome, Italy), Investigation of very-highfrequency nonoptical propagation between Sardinia and Minorca. Electrical Communication, N. Y. , 33(2): 133-142, June 1956. 10 figs. (incl. photo), foot-ref. -- The experiments with frequencies from 238 to 297 Mc show that operational telephony is feasible in spite of the not too optimistic results discussed. On this 240

mi path only 1% or 88 hrs of the year the performance will be worse than 46 db

adjusted, however, new techniques and instrumental improvement encourage fur- ther tests in process. The results are presented in graphs. --W. N.

E-365 Clarke, Robert F. (Meteorologist, Army Electronic Proving Ground, Fort Huachuca, Ariz.), The relation of physical conditions in the atmosphere to microwave

propagation. (1956). 29 p. 7 figs. , 6 refs. , 6 eqs. DWB (M94. 7 C599r)--

A method of forecasting microwave trapping or superrefraction in "ducts" at low

levels in the troposphere, was developed by the author at Fort Huachuca, Ariz,

since assignment there in Aug. 1955. The method involves forecasting the longest wavelength that will be trapped on the following morning and this depends on

forecasts of humidity, temperature, pressure and wind. In desert areas humidity

varies slightly. Observational and research program, as well as equipment and

theoretical basis for forecasting, is treated. No forecasts have been verified as

yet, although daily forecasts have been issued since Sept. 15, 1955. (Met. Abs.

8J-124)-M.R.

E-366 Clavier, Andre G. (Int. Teleph. & Telegraph Corp. ), Microwave communication

beyond the horizon. Electrical Communication, N. Y. , 33(2): 108-116, June 1956.

6 figs. , 18 refs. --Some of the major facts contributing to reliable transhorizontal

communication, including design of equipment, are discussed here. Basic at- tenuation curves of practical value are given and transmission levels within and

beyond the horizon as a function of frequency, are presented in graphs. Fading

margins in db related to wavelength from 6-300 cm are tabulated. --W. N.

E-367 Clavier, Andre G. and Altovsky, V. (both, Central Lab. of Communications,

Paris), Beyond-the-horizon 3000 megacycle propagation tests in 1941. Electrical

Communication, N. Y. , 33(2): 117-132, June 1956. 20 figs. (incl. photos), 2 footrefs. --The series of over land-sea experiments with 10 cm waves were conducted

around Toulouse, France, from May - Dec. 1941 with equipment developed during

the war and described here. Two different types of propagation were encountered,

viz: (1) the normal, in turbulent atmosphere resulting in steady and rapid attenuation beyond the horizon; (2) the abnormal, characterized by substantial increase

of range beyond the horizon and large amplitude variations. The latter observation disagreed with propagation theory in isotropic media. --W. N.

E-368 Crain, CM. and Williams, C.E. , Microwave refractometer predicts propagation.

Electronics, 29(12): 150-154, Dec. 1956. 6 figs. , 8 refs. -Changes in radiowave

propagation at the higher frequencies have been correlated with changes in refractive index of the atmosphere. Earlier investigations depended upon meteorological

data collection and evaluation. The airborne microwave refractometer directly measuring refractive index profiles has become a powerful tool in propagation studies.

--Authors' abstract.
89

Cunningham, Robert; Plank, Vernon G. and Campen, Charles M. , Cloud refractive index studies. U. S. Air Force. Cambridge Research Center, Geophysical

Research Papers, No. 51, Oct. 1956. 105 p. 65 figs, (some fold. , some photos),

29 refs. , 5 tables. DLC, DWB--An analysis of data obtained by various methods

in and around cumulus clouds is presented in detail in order to obtain a rough

idea of the variations in refractive index between clouds and free air or within

clouds or cloudy regions. Radiosonde data, cloud photographs, and aircraft re- fractometer and cloud physics measurements near Tucson, Ariz. ; Ft. Banks, Mass.;

Denver, Colo.; Yuma, Ariz.; Rantoul, 111. and Mt. Clements, Mich, in June and

July 1955 with a B-29 equipped with a U. of Texas model refractometer are reproduced. Soundings, cross sections, statistical graphs, cloud photos, refractive

index traces, etc. , are reproduced in extenso and the methods, equipment and

discussion of each day's flight treated in text. More knowledge of convective

cells in clouds is needed. (Met. Abs. 8 J-125)--M. R.

Epstein, J. and .Peterson, D. W. , A method of predicting the coverage of a television station . Radio Corporation of America, Review, 17(4):571-582, Dec. 1956.

8 figs. , foot -refs. DLC--A method is described for estimating television broadcast station field strength coverage for such uses as spectrum utilization studies.

The method is simple enough to be applied to studies involving a large number of

station locations; an estimate along an entire radial line can be prepared in a few hours. Practical confirmation of the validity of the method is shown in an example of its use. --Authors' abstract.

Fannin, Bob M. , Line-of-sight wave propagation in a randomly inhomoqeneous

medium. IRE Transactions on Antennas and Propagation, N. Y. , 4(4):661-665,

Oct. 1956. 5 figs. , 15 eqs. --Single scattering approximation is used in this

study, embodying the statistical quantities of variance, correlation function,

power spectrum, with stress on transition of ray treatment results to the scattering cross section results. The time and space dependency of the correlation

function for the refractive index facilities computation of the power spectrum.

»W. N.

Fok, V.A. , Priblizhennaia formula dlia dal'nosti qorizonta pri nalichii sverkhrefraktsii . (Approximate formula for horizon distance in the presence of superrefraction. ) Radiotekhnika i Elektronika, Moscow, l(5):560-574, May 1956.

117 refs. DLC--A formula is derived for the range of radio wave propagation

(horizon distance) in the presence of superrefraction. The formula obtained is

applicable to atmospheric ducts near the ground, in which the refractive index

is in a hyperbolic relationship with height. --Transl. of author's abstract.

Furutsu, Koichi, Field strength in the vicinity of the line of sight in diffraction

by a spherical surface. Japan. Radio Research Laboratories, Journal, 3(11):55-

76, Jan. 1956. 12 figs. , eqs. DWB--The convergence of the series of the ordinary Watson formula used for diffraction by a spherical surface becomes very bad

in the vicinity of the line of sight, and the formula is scarcely applicable for practical use in this domain. The problem of convergence of this kind can be

solved by suitable choice of the integration path. According to this" method the

formula is divided into two parts, one of which has the same expression as obtained in the case of a flat earth or obtained by the method of geometrical optics

or KIRCHOFF's approximation. The other part is expressed in the integral form

which is rather adapted to the numerical calculation. The latter thus explicitly
90

expresses the effect of diffraction or correction to the former. The method is

applied to several cases, and the results are displayed in figures in a useful

range of parameters. Some of these figures are especially convenient for calculation of field strength in diffraction by a spherical mountain or any mountain

having sufficiently large radius of curvature as compared with the wave length.

(Met. Abs. 8 J- 126) --Author's abstract.

E-374 Gerhardt, J. R. ; Crain, CM. and Chapman, H. (all, Univ. of Texas), Microwave refractive index fluctuations associated with convective activity in the

atmosphere. American Meteorological Society, Bulletin, 37(6):251-262, June

1956. 10 figs. , 8 refs. , eq. DWB. Also Gerhardt, J. R. and Crain, C. M. , Recent measurements of tropospheric microwave refractive index fluctuations

(Shorter version). Weather Radar Conference, 5th, Asbury Park, Sept. 1955,

Proceedings, pub. 1956. p. 43-44. DWB--This study deals with the results of a series of refractive index measurements made while flying at various constant

levels in the lower troposphere in and around Colorado and Florida. The refractometers used were sufficiently sensitive "to observe refractive index or equivalent

moisture content variations having frequencies up to 100 cycles per second and

amplitudes as small as 0.01 N-unit". The response, operation, installation of

the refractometer and the measurement program are described and recordings of

measurements under different atmospheric conditions are given. The observed

pattern of refractive index variations was found to be associated with the moisture changes in air masses "in which convective heat transfer from the ground is

contributing to the formation of rising warm, moist air thermals and cumulus

clouds". An indirect use of the refractometer is its value in the analysis of

these atmospheric processes either contributing to or producing tropospheric

mixing. (Met. Abs. 8J-127)--I.L.D.

E-375 Gerks, I.H. and Svien, A. J. , Wave propagation over a 350 mi path at 960 Mc . Institute of Radio Engineers, N. Y. , Convention Record, Pt. 1:3-8, 1956. 10

figs. , 4 refs. DLC--The object of this paper is to present some of the propagation results observed at 960 Mc over a 350 mi path. The path on which the

greater portion of the data was obtained extends from Lamar, Mo. to the Collins

Engineering Building at Cedar Rapids. Some results of tests made at intermediate points are also included. (Met. Abs. 8 J-128)--From authors' abstract.

E-376 Gorelik, G.S. , K teorii rasseianiia radiovoln na bluzhdaiushchikh neodnorodnostiiakh. (Theory of radio wave scattering by random inhomogeneities.

)

Radiotekhnika i Elektronika, Moscow, l(6):695-703, May 1956. 5 refs. , 36

eqs. --The scattering of radio waves by random inhomogeneities is considered

from the point of view of turbulent diffusion theory, treating the velocities of

inhomogeneities as stationary stochastic processes. A correlation is established between the time correlation function of the scattered field and some

statistical characteristics of random motions of inhomogeneities. --Transl. of

author's abstract.

E-377 Gossard, E. E. , Gravity waves in the lower troposphere over Southern California.

U.S. Navy Electronics Laboratory, San Diego Research and Development Report;

NEL/Report, No. 709, Aug, 9, 1956. 47 p. 30 figs. , 2 tables, 20 refs. , 26

eqs. DWB--Micro-oscillations of pressure of 5 to 20 min in the atmosphere at sea level (sometimes associated with sea surface fluctuations called Tsunamis),

are often noted at the meteorological station at Scripps Institute at La Jolla.
91

These may affect the refractive index and radio propagation. The detailed analyses

of Pibal, radiosonde data and surface wind, pressure, solar radiation, temperature,

etc. , show that the oscillations are internal gravity waves associated with temperature inversion surfaces. The waves can sometimes be seen and photographed

(examples included) and may affect several stations, thus showing contiguity over an expanse of 100 mi. The correspondence of the oscillations in wind direction,

speed and pressure are illustrated by a number of automatic traces superimposed

on the same time scale. The regular short duration oscillations are never associated with storms, but usually with a "Santa Ana" situation. Erratic, long duration oscillations are often associated with cyclones or fronts. (Met. Abs.

11.2-179)»M.R.

Gossard, E.E. and Anderson, L.J. , The effect of superrefractive layers on 50-

5000 Mc nonoptical fields. U.S. Navy Electronics Laboratory, San Diego, Calif.,

Research Report, No. 684, April 3, 1956. p. 175-178. 8 figs. , 4 refs. DWB.

Also issued in IRE Transactions on Antennas and Propagation, N. Y. , 4(2): 175-

178, April 1956. DBS—Radio propagation data taken over 82 naut.mi of water between San Diego and San Pedro, Calif, on 52, 100, 547 and 5000 Mc are analyzed

and compared with the atmospheric structure. Attenuation coefficients calculated

from the Furry model agree quite well with observational results at 100 Mc but not

for lower or higher frequencies. Conclusion is that for a given height of the top

of the superrefractive layer there is an optimum frequency for which attenuation is a minimum. (Met. Abs. 8 J-129)--M. R.

Gronlund, M. and Lund, CO., An electronic computer for statistical analysis of

radio propagation data. Akademiet for de Tekniske Videnskaber, Copenhagen,

Mikrobolgelaboratoriet, (Report) P 1992, Sept. 13, 1956. --The equipment in use

at the laboratory is described in some detail along with future improvements. Pen

recordings of the field strength are transferred into a five digit binary code (by a manually operated curve converter) and stored as perforated punched teletype

tape, from which the statistical analysis is made by electronic equipment permitting reading of data at 1000 numbers per sec. Distribution curves, single set as

well as for a diversity system, are handled. (Met. Abs. 8 J-130)--From authors'

abstract.

Grosskopf, J. , Uber den auaenblicklichen Stand der Forschung auf dem Gebiet

der troposphanschen Streustrahlunq. Teil 1. (Present state of research on tropospheric scatter propagation, Pt. 1.) NTZ: Nachrichtentechnische Zeitschrift, Brunswick, 9(6):272-279, June 1956. Pt. 2. Ibid., 9(7):315-329, July 1956. 49 figs. , 25 refs. , 69 eqs. DLC—The purpose of this paper is to summarize current out- standing contributions, particularly the American works in the October 1956 issue

of the Institute of Radio Engineers, Proceedings. --W. N.

Grosskopf, J. and Vogt, K. , Der Einfluss von Bodeninhomoqenitaten auf die

Funkbeschickunq. (The influence of surface inhomogeneity on radio coverage.

)

NTZ: Nachriochtentechnische Zeitschrift, Brunswick, 9(8):349-355, Aug. 1956.

13 figs. , table, 6 refs. DLC--The surface properties of a site of radio receiver

and transmission installations may affect the efficiency and the radiative distribution of the antennas and cause bearing errors of direction finding stations.

Comparative measurements conducted within the circumference of a direction

finder station of conductivity and of bearing errors yielded a linear relation between the maximum conductivity variation o max/ $ min and the mean bearing
92

error °( 6 max/ tfmin = 4 yields & = 1 ). Exterior reflectors, such as cables

and power lines, showed bearing errors of 0. 5°, 10°, and 20°, caused by (1) an uncharged cable ending right below the station, (2) charged with counter balance,

and (3) a traversing cable respectively. Discontinuity points of conductivity

yielded a maximum of 2°. However, determination of the azimuthal distribution

of conductivity measurements is rnly feasible under simple surface conditions.

--G.T.

E-382 Hirao, Kunio, Fading of the ulfra short wave and its relation to the meteorological

conditions . Japan. Radio Research Laboratories, Tokyo, Journal, 3(13): 191-255,

July 1956. 47 figs. , table, 33 refs. DBS-Data on 65.82 Mc wave reception at various localities (transmitted from Hiraiso Observatory) are compared with meteorological data (temperature and wind fluctuations, refractive index, etc.) by means

of autocorrelation analysis. The techniques used, including the meteorological

equipment at Tateno Aerological Observatory, and the statistical method are described in detail. Fading is found to be composed of three parts due to scintillation, scatter and interference between the diffracted and reflected wave, respectively. The period of scintillation fading is nearly equal to the duration of refractive index irregularity or its turbulence; scatter fading is inversely proportional

to turbulent velocity. A complete schematic model of fading is worked out and

applied to a number of different propagation conditions. --G.T.

E-383 Hooper, A.H. , Abnormal VHF propagation: determination of radio refractive

index structures from weather data . Wireless World, London, 62(6): 295-298,

June 1956. 3 figs. , 3 tables. DLC--V.H. F. propagation is related to vertical

structure of radio refractive index. A method is given of plotting this variation

with height up to 8000 ft from pressure and "refraction temperature" Tr based on observed temperature and humidity. A graph of Tp against air temperature and

dew point, and instructions for preparing and using a plotting chart, are given.

(Met. Abs. 8.4-83)--C.E.P.B.

E-384 Hooper, A. H. and Taylor, A. P. , Radio refraction in the free atmosphere . Great

Britain. Meteorological Research Committee, M. R. Papers, 1021, Dec. 31, 1956.

6 p. 2 figs. , 4 tables, ref. , 5 eqs. Mimeo. DWB--The theory of refraction, and

the refractive index structure of the atmosphere, are set out. The refraction cor- rection of radar heights is calculated for I.C. A. N. moist atmosphere. Further

corrections are considered for I. C.A.N, dry atmosphere, and for low level

European and sub-tropical moisture discontinuities. (Met. Abs. 8 J-13D--C.E.P.B.

E-385 Hopkins, R.U.F. ; Smyth, J. B. and Trolese, L. G. , The effect of superrefraction on the high altitude coverage of ground based radar. U.S. Navy Electronics Laboratory, San Diego, Calif. , NEL Report 741, Dec. 12, 1956. 19 p. 12 figs. (incl.

photos), 11 refs. DWB (M055 U585r, No. 741) -The effects of a standard atmosphere and of ducts and elevated layers on propagation (reflection, refraction and

ducts) of 218, 418 and 1089 Mc coverage at distances up to 150 mi and heights

up to 60,000 ft are discussed, and nomograms are presented showing characteristics of propagation. The details of the experimental procedures used to test the

effects of index of refraction anomalies on high angle propagation, using high flying jet planes, between Jan. 1953 and June 1955 over the Pacific Ocean west of

Los Angeles, are set forth. It was found that both by theoretical and experimental

means, the distribution of field strength at angles 1° above the horizon is not appreciably affected by inversions or other atmospheric inhomogeneities at 218, 418
93

or 1089 Mc. A series of diagrams show index of refracting profiles and variations

of field strength with distance for vertically and for horizontally polarized radiation at frequencies of 218, 418 and 1089 Mc for distances up to 300 mi for alti- tudes of 28,000-39,000 ft. The presence of strong temperature inversions or ducts

at low altitude results in loss of energy in region from the horizon to 1° or so above

the horizon. Normally there are large "lobes" of field strength intensity but these

may be broken up into fine "spikes" if low altitude index of refraction changes are

large. (Met. Abs. 8J-132)-M.R.

E-386 Iakovlev, O. I. , Uchet vysot antenn v teorii troposfernogo rasseianiia metrovykh

radiovoln. (Taking antenna height into account in the theory of tropospheric scattering of meter waves. ) Radiotekhnika i Elektronika, Moscow, 1(3):309-312,

1956. 3 figs. , 3 refs. , 12 eqs. DLC. English translation available from Morris

D.Friedman, Inc., Needham Heights, Mass., as their MDF 1-112. -The dependence

of field strength well beyond the horizon on antenna height is investigated on the

basis of tropospheric scatter propagation theory. It is shown that interference in

the region of scattering has to be taken into account in calculating the scatter field.

By accounting for interference between the direct waves and those reflected from

the ground it is possible to determine the dependence of the received signal intensity on antenna height. (Met. Abs. 8 J-179)--Transl. of author's abstract.

E-387 Jones, D.E. , A critique of the variational method in scattering problems . IRE

Transactions on Antennas and Propagation, N. Y. , 4(3):297-301, July 1956. 6 refs.,

24 eqs. --The equivalence of the variational method and Galerkin's method is pre- sented. The reciprocity theorem is complied with in terms of it, rather than introducing the variational principle. --W. N.

E-388 Kalinin, A.I. , Dal 'nee rasprostranenie ul'trakorotkikh voln za schet rasseianiia v troposfere . (Distant propagation of US waves by means of tropospheric scatter.

)

Elektrosviaz', Moscow, No. 5:37-44, May 1956. 11 figs. , 7 refs. , 4 eqs. DLC--

Foreign (non-Russian) literature on tropospheric scatter propagation of ultrashort

waves over great distances is reviewed. --Transl. of author's abstract.

E-389 Kamen, Ira and Doundoulakis, George (both, General Bronze Corp. .Electronic

Div. , N. Y. ), Scatter propagation, theory and practice. Indianapolis, Howard

W.Sams & Co. , Oct. 1956. 197 p. 141 figs. (incl. tables), eqs. DLC -This book,

written by design engineers, deals with design problems of tropospheric equipment.

The general theory on scatter propagation of radio waves is given and discussed in

relation to the ionosphere and troposphere. Several meteorological aspects influencing reliability, range and maintenance of tropospheric equipment for transhorizontal, local and/or worldwide radio communication are discussed. Tabulated and

graphical presentation, as well as excellent photographs, enhance the value of the

work. (Met. Abs. 8J-133)--W. N.

E-390 Kirby, R.S.and Capps.F. M. (both, U.S. Nat'l. Bureau of Standards, Central

Radio Prop. Lab. .Boulder, Colo.), Correlation in VHF propagation over irregular

terrain. IRE Transactions on Antennas and Propagation, N. Y. , 4(l):77-85, Jan. 1956. 10 figs. , 6 refs. DBS--A study has been made of the correlation in trans- mission loss observed over irregular terrain paths. Simultaneous mobile measure- ments were made of two pairs of VHF broadcasting stations in the Wash. .D.C.-

Baltimore, Md. area. The correlations coefficients derived from sample sets of

transmission loss data indicate that when reception is from opposite directions,
94

no significant correlation is evident, and when the paths of propagation are the

same, even though the frequencies are separated considerably, the correlation

appears to be significantly high. (Met. Abs. 8 J- 134) --Authors' abstract.

E-391 Kirby, R.S.; Dougherty, H. T. and McQuate, P.L. , VHF propagation measure- ments in the Rocky Mountain region. IRE Transactions on Vehicular Communications, N. Y. , Vol. PGUC 6:13-19, July 1956. 6 figs. , 5 refs. NBS -Mobile measurements of VHF propagation over various irregular terrain paths have been made

by the National Bureau of Standards in the Colorado Rocky Mountain region in an

effort to evaluate terrain effects upon broadcast and point-to-point communications at very high frequencies. Mobile measurements of the varying path trans- mission loss were obtained in a continuous manner, while driving along selected

routes with a mobile field strength recording unit, which consists of a modified

house trailer equipped with a telescoping mast and pulled by a pick-up truck. The

paths used ranged from relatively smooth to very rough. The results of the measurements are considered in the light of current irregular terrain theory. The cor- relation of sector median transmission loss for different frequencies over irregular

terrain tends to be high when the paths are nearly the same, becoming significantly less when the paths diverge. This would indicate that the frequency selectivity of an irregular terrain path is small. --Authors' abstract.

E-392 Klinker, L. , Fernempfangsbeobachtunqen im 3-m Rundfunkband. (Observations

of distant reception at 3 m wavelength. ) Hochfrequenztechnik und Elektroakustik,

Leipzig, 65(3):77-86, Nov. 1956. 16 figs. , 2 tables, 20 refs. DLC--A study of

several years of ultrashort wave (3 m) propagation data supports the validity of the

CCIR curves as far as the Central European area is concerned. The long distance

field fluctuations are found to be closely related to weather conditions. --Transl. of

author's abstract.

E-393 Klinker, L. (Kuhlungsborn Met. Obs. , East Germany), Meteoroloqiai befolyasok

a rovid periodusu elhalkulasok kialakulasara az ultrarovid hullamu tavolsagi

forgalomban. (Meteorological influences on the production of fadings of short

duration in VHF long distance communication. ) Idcjaras, Budapest, 60(4):212-

221, July/Aug. 1956. 7 figs. , 12 refs. Russian and English summaries p. 212.

German version p. V-X. DLC--By observations of wave propagation made during

special synoptic situations, the author has been led to the assumption that two

peculiar types of VHF fadings are produced by atmospheric dispersion and by

partial reflections on free inversion surfaces. (Met. Abs. 8 J-135) --Author's abstract.

E-394 Krasil'nikov, V. A. and Obukhov, A.M., Propagation of waves in a medium with

random inhomogeneities of the index of refraction (Survey). Soviet Physics:

Acoustics, N. Y. , 2(2):103-110, 1956. 2 figs. , 23 refs. , 26 eqs. Transl. of

original Russian in Akusticheskii Zhurnal, Moscow, 1956. DLC--The survey is

devoted to the problem of "waves and fluctuations" which in recent years has

been developed in connection with a number of problems of atmospheric acoustics,

hydroacoustics, atmospheric optics and the propagation of radio waves in the

troposphere. More particularly, the authors discuss the study of phenomena arising during the propagation of waves in a medium with weak random inhomogeneities

caused by turbulence. The authors have written a number of papers on this subject;

certain results of these papers are briefly discussed along with the results of a number of other authors (mostly Russian). (Met. Abs. 10 G-81) --From authors'

abstract.
95

Lucy, R.E. and Sharp, C.E. , Radar-type propagation survey experiments for communication systems . Institute of Radio Engineers, N. Y. , Convention Record,

Pt. 1:20-27, 1956. 9 figs. DLC--A technique for conducting rapid UHF and microwave propagation surveys is described. Experiments have been made using the

terrain backscatter patterns of a radar PPI scope. The results are discussed and

illustrated with photographs. (Met. Abs. 8 J-136)--From authors' abstract.

Maenhout, A. , Gunstige voortplantinqsvoorwaarden voor zeer korte golven.

(Favorable propagation conditions for very short waves.) Hemel en Dampkring,

The Hague, 54(2):40-41, Feb. 1956. Fig. DWB, DLC--The propagation of very

short wave radiation as a function of atmospheric refraction which is influenced

by atmospheric conditions is outlined and the unusually favorable propagation of

very short waves on Jan. 6, 1956 is explained by the magnitude of the refractive

index at Uccle which increased the propagation of the 3 m band by 32%. (Met.

Abs. 8J-137)--I.L.D.

Millman, George H. (General Electric Co. , Syracuse, N.Y.), Analysis of tropospheric. ionospheric and extraterrestrial effects on VHF and UHF propagation.

General Electric Co. Electronics Div. , Technical Information Series, R56EMH31,

Oct. 6, 1956. 138 p. 68 figs. , tables, 50 refs. , numerous eqs. Photostat copy.

DWB (M94. 7 M655an) --Effects of the atmosphere and extraterrestrial noise sources on the propagation of VHF and UHF radio waves are discussed. Relationships are derived for calculating refraction effects, time delays, Doppler

errors, polarization changes and attenuation of radio waves traversing the atmosphere. These conclusions were reached. Refraction and time delay effects in

the troposphere are independent of frequency and are a direct function of relative

humidity in the air. In the ionosphere refraction and time delay errors, polarization shift and attenuation are inversely proportional to the square of frequency.

The Doppler frequency error in the troposphere is directly proportional to frequency

while in the ionosphere is inversely proportional to frequency. The theoretical

total radiation from the quiet sun, in the radio frequency spectrum, is directly proportional to frequency raised to about the 0. 755 power. The total flux density

emanating from radio stars, Cassiopea and Cygnus, is inversely proportional to the frequency raised to the 0.81 power. (Met. Abs. HE-99)--Author's abstract.

Misenheimer, Harvey N. , "Over-the-horizon" radio tests. Telephony, 151(5):

22-24, 38, Aug. 4, 1956. 7 figs. -This is an account of a full year, 1953-54,

investigations conducted in Newfoundland over land-sea paths under different

weather and transmission conditions, at frequencies of 505 and 4090 Mc. The

results are presented graphically and include the influence of weather, snow

and fog on transmission. --W. N.

Misme, P. , Methode de mesure thermodvnamiaue de l'indice de refraction de

l'air Description de la radiosonde MD1. (Thermodynamic method of atmospheric

refractive index measurements. Description of the MD1 radiosonde. ) Annales

des Telecommunications, Paris, ll(4):81-84, April 1956. 6 figs. -A radiosonde

is described, which measures temperature, pressure and humidity, from which re- fractive index values can then be calculated. The instrument is described and

shown in detailed diagrams. A sample sounding record is presented; it shows

that refractive index variation with height shows a pattern similar to that of the

humidity variation. This fact would have gone unnoticed if the refractive index

had been determined with a radio method. Thus the thermodynamic method of

refractive index determination is better suited for relating propagation anomalies

to meteorological phenomena. --G.T.
96

E-400 Moler, W. F. and Arvola, W. A. , Vertical motion in the atmosphere and its effect on VHF radio signal strength. American Geophysical Union, Transactions, 37(4):

399-409, Aug. 1956. 10 figs. , 5 refs. , 6 eqs. DWB, DLC--The hypothesis is

proposed that the vertical gradient of the refractive index is strongly affected by

the vertical motion in the atmosphere. It is shown that changes in this gradient

are due principally to changes in the moisture stratification and temperature lapse

rate resulting from the vertical velocity and its horizontal gradient within the air mass. Mean radio signal strengths are plotted against the time position of 500 mb

troughs and ridges relative to the radio link. A series of 500 mb charts is given,

with the vertical velocity field obtained by the Sawyer-Bushby method. The vertical velocity over two radio links is compared with the signal strength. Cross sections taken through several of the troughs illustrate the stratification changes on

the forward and rear sides of the troughs due to vertical motion. (Met. Abs.

8. 4-247) -Authors' abstract.

E-401 Morrow, W. E. , Jr. ; Mack, C.L.,Jr. ; Nichols, B. E. and Leonhard J. , S ingle - sideband techniques in UHF long range communications. Institute of Radio Engineers, N. Y. , Proceedings, 44(12): 1854-1873, Dec. 1956. 31 figs. , Stables,

25 refs. , 9 eqs. --Several factors relevant to the design of UHF long range communication systems are analyzed. In particular, single sideband amplitude modulation is evaluated and compared to frequency modulation, with special regard to

a) spectrum conservation; b) performance in the presence of multipath; and c)

realized channel signal to noise ratio vs total transmitted rf power. It is shown

that 1) SSB requires one sixth to one tenth of the spectrum width required by fm,

2) the useful bandwidth of the transmission medium in the presence of multipath

is at least four times as great for SSB as for fm, 3) the average power required

for a 24 channel SSB system is about 20 decibels less than that required for an

equivalent fm system, providing equal usable communications. System design

considerations are discussed for UHF single sideband, as well as the design

parameters of a particular set of equipment operating in the 300 to 400 megacycle

band. The linearity of high power klystrons is discussed and a promising technique for achieving highly efficient operation of such devices is described.

--Authors' abstract.

E-402 Moyer, Vance E. , Preliminary synoptic analyses of the atmospheric refractive

index climatology of Alaska and the Western United States coastal waters. Weather Pi adar Conference, 5th, Asbury Park, N. J. , Sept. 1955, Proceedings, pub.

1956. p. 45-61. 12 figs. DWB--The synoptic climatological approach is used in

the study of the microwave refractive index conditions in Alaska, the Aleutians

and Northwest Canada. Radiosonde data from a fairly dense network of stations

are used to obtain daily maps showing the regional distribution of the vertical

gradient of refractive index (1000 - 850 mb) and of the absolute value of this

parameter at 850 mb. A few of the maps for Sept. 1953 which were prepared in

this study are reproduced and discussed. Another study of the horizontal and

vertical variations of the low level refractive index profiles off the California

coast was made on the basis of airborne refractometer measurements made between Aug. 4 and Oct. 29, 1954. (Met. Abs. 8J-138)--M. R.

E-403 Norton, Kenneth A. , Point-to-point radio relaying via the scatter mode of tropospheric propagation. Institute of Radio Engineers. IRE Transactions on Communications Systems, N. Y. , 4(l):39-49, March 1956. 7 figs. , table, 32 refs. , 29 eqs. DLC --Formulas are given for determining the transmitter power required

to provide a specified grade of service in point-to-point radio relaying of the
97

following types of signals: television, frequency modulation high fidelity music,

frequency modulation voice, frequency shift telegraph, and a just measurable

signal. Allowance is made for the antenna gains, the carrier frequency, the system bandwidth, distance, the antenna heights above the ground and the effects of

the terrain and the atmosphere along the transmission path. The formula for the

transmission loss allows separately for the effects of the actual distance, the

angular distance and the antenna heights, and this separation of the influence of

these variables provides the basis for the development of rules for the efficient

siting of the terminals of a tropospheric forward scatter relay circuit. (Met.

Abs. 8 J- 180) --Author's abstract.

E-404 Plank, Vernon G. , A meteorological study of radar angels. U. S. Air Force. Cambridge Research Center, Geophysical Research Papers, No. 52, July 1956. 117 p. 29 figs. , 4 tables, 113 refs. , 24 eqs. DWB, DLC--Three different types of angels

are recognized: .1) layer angels; 2) localized source angels, and 3) erratic angels.

Their nature, size, meteorological conditions favoring each type, other sources

(insects and birds or dust), refractive index inhomogeneities, the history of angels

of each type, and a thorough bibliography are presented in this monograph. A tre- mendous amount of theoretical, graphical and tabular data are analyzed and incorporated in the text. Work is based on radar soundings at Round Hill, Mass. in

1951-53 and on work of others in this field. Of all the possible sources, refractive index inhomogeneities are found to be the most common. Activity is the greatest with high temperature, moisture content and light winds, and with pronounced

convective activity. (Met. Abs. 8J-14D--M. R.

E-405 Poeverlein, H. , Eine einfache Theorie der Beugung von Radiowellen jenseits des

optischen Horizonts. (A simple theory of radiowave diffraction beyond the horizon.)

Zeitschrift fur Angewandte Physik, 8(2):90-95, 1956. TransL into English (15 p.

issued by U.S. Air Force Cambridge Research Center, as its AFCR-TR-116, Sept.

1957. (ASTIA Document, No. AD 1337 II). 2 figs. , 3 tables, 15 refs. , 9 eqs. -- Repeated application of Huygen's principle leads to a field strength formula for waves diffracted around the curved earth which is identical with the approximation

of the Van der Pol-Bremmer theory. The ground constants enter through the consideration of the reflected waves, especially the reflected Huygens elementary waves. The influence of the ground can be expressed by a parameter which appears in the properly written Fresnel reflection coefficient of the ground. In order

to have the diffraction theory valid, certain assumptions have to be fulfilled.

Irregular inclination of the earth's surface of inhomogeneities of the atmosphere can make the theory more or less useless for the shorter wavelengths. --Author's

abstract.

E-406 Poeverlein, H„ , Grosse Reichweiten von m-. dm- und cm-Wellen. (Long ranges

ofVHF, UHF, andSHF.) Zeitschrift fur Angewandte Physik, 8(5):244-254, 1956.

TransL into English (30 p. ) issued by U.S. Air Force Cambridge Research Center, as its AFCR-TR-57-117, Sept. 1957. (ASTIA Document, No. AD 133712). 8 figs.,

table, 63 refs. , 24 eqs. --This paper was dedicated to Geheimrat Zenneck on his

85th birthday. The main topics discussed are the diffraction around the earth and

the refraction in the troposphere as causative agents for reception just beyond the

horizon and its irregularities, typical for waves shorter than 10 m. It is shown

that the scattering cross section depends mainly on the vertical extension of the

scattering centers. The integration would remain unchanged by horizontal extension, however, increase the field strength at reception point in direction of

specular reflection, otherwise decrease. --N. T. G.
98

E-407 Potts, D.H. ; Rempel, R.W. and Goss, R. N. , A summary of the symposium on

normal mode theory. July 5-7. 1955. U. S. Navy Electronics Laboratory, San Diego,

Research Report; NEL Report, No. 718, Oct. 9, 1956. 26 p. 8 figs. , 13 refs. , eqs. DWB--The symposium, held at the Navy Electronics Laboratory, San Diego,

Calif. , on July 5,6 and 7, 1955, under the chairmanship of S. A. SCHELKUNOFF

of Bell Telephone Laboratories, and jointly sponsored by the Office of Naval Research, Navy Engineering Laboratory, and Ryan Aeronautical Company, consisted

of a round table discussion of theoretical knowledge of wave propagation through

stratified media, methods of solution of problems, and outstanding problems yet

to be solved. No formal papers were presented. The subjects discussed were ray

theory, Huygens' principle, normal modes, Sommerfield surface wave, and propagation beyond the horizon. Appended is a paper by FRIEDMAN on Normal modes

in tropospheric propagation . (Met. Abs. 8 J- 142) --Partly from summary and M. R.

E-408 Pressey, B. G. ; Ashwell, G. E. and Fowler, C.S. , Change of phase with distance

of a low frequency ground wave propagated across a coast line . Institution of

Electrical Engineers, London, Proceedings, Pt.B, 103(10): 527-534, July 1956.

14 figs. , 4 refs. DLC --Observations of the change of phase with distance have

been made on frequency of 127. 5 kc/s along a number of path radiating from a transmitter near Lewes and crossing the south coast between Pevensey and Little

hampton. The nature of the ground adjacent to the coast, the angle of crossing

the coast line and the length of the land and sea sections covered varied from

path to path; the greatest distance covered out to sea was 22 km. Measurements

were also made over path at right angles to the radials, and phase changes in the area off Worthing, where the path was tangential to the coast, were examined in

detail. The results confirm the existence of a phase recovery effect which, as

theoretical considerations have shown, should be experienced by a wave passing

from low conductivity ground to sea water and which was indicated by previous

measurements over geological boundaries on land. The detail of the measurements

at sea shows also that, in addition to this general behavior of the phase, there are superimposed systematic variations whose magnitudes decay from about 4° of phase

near the coast to a negligible amount at 6 % out to sea and on some paths are comparable to the recovery. A very marked phase disturbance within "\/2 of the coast

on the landward side is also evident; it is similar to that previously observed over geological boundaries on land. —Authors' abstract.

E-409 Rivet, Pierre, Essais de diversite et eiude de l'effet de focalisation sur des

liaisons longues en visibilite. (Diversity experiments and study of the effect of

focusing on communication over long optical paths.) L'Onde Electrique, Paris,

36(346): 23-31, Jan. 1956. 6 figs. , 2 tables. DBS -Results of propagation ex- periments over a 230 km overwater path (Mt. Agel, France, elev. 1140 m, La Punta,

Corsica, elev. 750 m) are reported. The experiments involved simultaneous use

of diversity in height and frequency. It is found that the multiple path hypothesis

cannot account for the field variations observed. --G.T.

E-410 Saxton, J. A. , Tropospheric scatter propagation. Wireless World, London,

62(12): 587-590, Dec. 1956. 2 figs. DLC-Latest theories concerning the possibilities of extending communication beyond the horizon by means of microwaves

are reviewed. It has been found that links operating on the scatter principle are capable of carrying wide banded information and are suitable for relaying multichannel telephony over paths of a few hundred miles. The reliable transmission

of television signals will follow probably as the technique develops, though, in

view of the bandwidth required, the length of a link for this purpose will generally

be less than is possible for telephony and telegraphy. --E. K.
99

E-411 Saxton, J. A. and Harden, B. N. , Polarization discrimination in VHF reception. Institution of Electrical Engineers, London, Proceedings, Pt.B, 103(12): 757-760,

Nov. 1956. 5 figs. , table, foot-ref. DLC--An account is given of measurements

in the band 40-200 Mc/s of the discrimination likely to be achievable between

common frequency transmissions by the use of orthogonal polarizations. It is shown that the discrimination is determined primarily by the topographical nature

of the receiving site, that it is substantially independent of distance from the

transmitter and of frequency in the band under consideration, and that the median

value is about 18 db. The perturbing effects of pick up on the feeder and of re- ceiving aerial misalignment are discussed. —Authors' abstract.

E-412 Schachenmeier, Richard, Einige Forschungsarbeiten uber die Ausbreitunq ultra - kurzer Wellen . (Investigations on the propagation of ultra short waves. ) Akademie

der Wissenschaften, Berlin, Wissenschaftliche Annalen, 5(7): 589-603, July 1956.

10 figs. , 10 refs. , 8 foot-refs. , 14 eqs. DWB, DLC--The author reviews several

investigations in which it was attempted to measure and calculate the tropospheric

conditions influencing the reception intensity of ultrashort radiation in the case of

relatively short distances and low antennae heights. (Met. Abs. 8 J-143)--I.L. D.

E-413 Schensted, C.E. , Approximate method for scattering problems. IRE Transactions on Antennas and Propagation, N. Y. , 4(3):240-242, July 1956. 3 figs. , 16 eqs. -- Two examples of the method are given, viz: scattering by (1) a half-plane and (2)

by a circular disk. The solution of satisfying certain boundary conditions, which

was the purpose, is given. --W. N.

E-414 Schmelovsky, Karl-Heinz, Partielle Reflektionen in schwachen tropospharischen

Wellenleitern. (Partial reflections in weak tropospheric wave-ducts. ) Zeitschrift

flir Meteorologie, 10(8): 239-243, Aug. 1956. 2 figs. , 6 refs. , 8 eqs. DLC--

This work describes an approximation process for obtaining the propagation constants in weak ducts. A diagram collects the results for some special height re- lations of the modified refraction index. (Met. Abs. 8.4-343)--Transl. of author's

abstract.

E-415 Shabel'nikov, A.V., Vliianiia vida funktsii raspredeleniia dielektricheskoi pro- nitsaemosti vozdukha s vvsotoi

1 na refraktsiiu radiovoln v nizhnikh sloiakh

atmosferv. (Influence of the form of the vertical distribution function for dielectric permeability of the air on the refraction of radio waves in the lower layers of

the atmosphere.) Radiotekhnika i Elektronika, Moscow, l(3):277-280, 1956.

Fig. , 5 refs. , 13 eqs. DLC--The dependence of the angle of refraction on the vertical distribution of atmospheric dielectric permeability is analyzed theoretically

by means of a method of variation calculation. It is shown that no such depend- ence exists at zenith angles comprised between 0° and 80°. (Met. Abs. 8J-181)

--Transl. of author's abstract.

E-416 Silverman, Richard A. (Inst, of Math. Sciences, N. Y.Univ. ), Turbulent mixing

theory applied to radio scattering . Journal of Applied Physics, 27(7): 699-705,

July 1956. 2 tables, 18 refs. , eqs. DLC --OBUKHOFF ' s statistical theory of tur- bulent mixing is proposed as a replacement for the heuristic theories of GALLET

and VILLARS-WEISSKOPF, and is applied to the problem of the scattering of radio

waves by refractive index fluctuations. In the case of ionospheric scattering,

order of magnitude agreement with the observed scattered power is obtained if
100

the refractive index fluctuations are attributed to electron density fluctuations

produced by turbulent mixing in the lower edge of the E layer. In the case of

tropospheric scattering, it appears that order-of -magnitude agreement with the

observed scattered power can be obtained, except during the summer months,

by attributing the refractive index fluctuations to temperature fluctuations. During the summer months and at low scattering heights, humidity and its fluctuations are expected to play a prominent role. Experimental and theoretical evidence is cited in favor of perennial fractional degree temperature fluctuations

in the troposphere. A comparison of the Obukhoff, Villars-Weisskopf, and

Booker-Gordon models is given, and it is found that the Obukhoff model predicts

the most scattered power. (Met. Abs. 8 J- 144) --Author's abstract.

E-417 Staras, Harold, Scattering of electromagnetic energy in randomly inhomogeneous

atmosphere. Journal of Applied Physics, 23(10): 1152-1156, Oct. 1956. 15 eqs.

DLC--It is demonstrated that the integral expressions as used by PEKERIS,

BOOKER and GORDON are not appropriate to use as a space correlation function

of refractive index. Here is introduced a time correlation instead which permits

direct measurement of. the time correlation function and formal evaluation of the

time average scattered power, which is shown to depend but little on any particular model of turbulence. However, in its large scale turbulence condition it is

affected greatly by the time correlation chosen or by the assumption that scatter- ing is a result of randomly located spheres. (Met. Abs. 8 J-145)--From author's

abstract.

E-418 Starkey, B. J. , Some aircraft measurements of beyond-the-horizon propagation

phenomena at 91.3 Mc/s. Farnborough, England. Royal Aircraft Establishment,

Technical Note, No: RAD. 638, March 1956. 4 p. 4 figs. , 7 refs. Mimeo.

GB-MO. Also in: Institution of Electrical Engineers, Proceedings, Pt. B, 103(12):

761-763, Nov. 1956. 4 figs. , 8 refs. , eq. DLC—Field strength measurements on

an aircraft at 10, 000 ft 150-430 mi from source (Wrotham) showed an initial de- crease slower than expected from diffraction theory, maxima at about 250 and 300

mi, deep and regular fades beyond 350 mi and a rapid drop to noise level at 420

mi. Horizon was about 175 mi. The extended range is attributed to specular re- flection from a tropopause discontinuity of refractive index at 38, 000 ft shown by

radiosonde at Lerwick. The fluctuations are explained by interference between

various rays. (Met. Abs. 8. l-396)--C. E. P. B.

E-419 Straiton, A. W. and Tolbert, C. W. , Measurement and analysis of instantaneous

radio height gain curves at 8. 6 millimeters over rough surfaces . IRE Transactions on Antennas and Propagation, N. Y. , 4(3):346-351, July 1956. 13 figs. , 4 refs.

--The data analyzed and discussed were taken on a radio path over Lake Austin,

Nov. 1954, A specific antenna system was constructed for obtaining proportional

height gain curves in a very short time interval. The vector sum of the direct, a constant reflected, and a varying reflected wave may represent the fluctuation

of the radio signal measured. --W. N.

E-420 Suzuki, Michiya and Hasegawa, Taro (both, Yamagata Univ. Faculty of Engineering) , Vertical distribution of radio meteorological M-curve for near the snow

covered terrain . Seppyo (Snow and Ice), Tokyo, 18(2):48-55, Aug. 1956. 8 figs. , 7 refs. In Japanese; English summary p. 48. DWB—The variation of the equivalent

reflection coefficient (Pe) is one of the most important factors which determine the

properties of K Type Fading at microwave propagation over snow covered terrain.
101

And Pe's physical meaning is somewhat complicated by the reason that it contains

many factors (surface deposited snow's dielectric properties, radio meteorology,

etc.). So we observed Pe's daily variation at the model propagation test (at very

short distance 100 m, 4000 Mc/s) and annexed the radio meteorological condition's measurements. This paper shows the method of this experiment and the

analytic results on the radio meteorological M curve (M profile lies on the very

low layer near upon the model test's reflection point). The vertical profiles of

measured atmospheric temperature and M curve are represented in Fig. 4 and

A M (M - inversion) in Fig. 6, respectively. In general, the variation of A M is

smaller than over the land and sea, especially at night time. So it is found that

the dielectric properties of deposited snow at reflection surface had probably a

pretty large influence on the variation of Pe. (Met. Abs. 8 J- 147) --Authors'

abstract.

-421 Symposium on .electromagnetic wave theory, Univ. of Michigan, June 20-25, 1955,

Report of conference . IRE Transactions on Antennas and Propagation, 4(3): 191-

586, July 1956. --This issue is devoted entirely to the symposium and contains:

boundary value problems of diffraction and scattering theory (19 papers). For- ward and multiple scattering (9 papers). Antenna theory and microwave optics

(10 papers). Propagation in doubly refracting media (7 papers). Summaries of

the panel discussions (5 papers). Appendix: Abstracts of the contributed papers.

A-l, Scattering, diffraction and general mathematical papers (17 abstracts).

A-2, Multiple scattering, scattering from rough surfaces, and transmission and

reflection problems (10 abstracts). A-3, Wave guides, propagation, and slow

waves and surface waves (10 abstracts). A-4, Ferrities, plasma oscillations

and anisotropic media (8 abstracts). A-5, Antennas and microwave optics (8

abstracts). Author index. --W. N.

-422 Tao, Kazuhiko, Some consideration for the field strength of ultra short waves at night. Japan. Radio Research Laboratories, Journal, 3(ll):77-99, Jan. 1956.

15 figs. , 15 refs. DWB--This analytical study is based on two years of transmission experiments conducted at the Radio Research Laboratories of Japan. Fre- quencies at 150 and 60 Mc were used over the 125 km path fron Kokubunjii to Hiraiso, the latter located in diffraction region. It is shown that super high field

strength at night is a function of a tropospheric M layer formod by abnormal water

vapor distribution and associated with temperature inversion. This formation is

discussed in terms of synoptic meteorology. It is suggested that prediction of

hourly median field strength of USW is greatly facilitated by these analyses.

(Met. Abs. 8J-148)--W. N.

-423 Tatarskii, V.I., O pul'satsii amplitudy i fazy volnv. rasprostraniaiushcheisia

v slaboneodnorodnoi1 atmosfere . (The pulsations of amplitude and the phases of

waves propagated in a moderately heterogeneous atmosphere. ) Akademiia Nauk

SSSR, Doklady, 107(2): 245-248, March 11, 1956. 4 refs. , 23 eqs. DLC--The

problem of the propagation of waves in a medium with a moderately heterogeneous

coefficient of refraction is treated theoretically and a more simple and practical

solution than that of A. M.OBUKHOV is obtained. The coefficient of refraction

is assumed to he7l - 71/ + 1 + (/Z-), where 7?. (A,) is the deviation of the coefficient

of refraction from the mean value (unity) and that ^ :£ 1. Equations for calculating

the scintillation of stars and analogous phenomena are presented. (Met. Abs.

8.9-204)-I.L.D.
102

E-424 Troitskii, V. N. , O vozmozhnoi polose peredachi v sluchae dal'nego troposfernoqo rasprostraneniia. (Possible transmission band for long range tropospheric

propagation. ) Radiotekhnika, Moscow, 11(9) :3-7, Sept. 1956. 3 figs. , 2 refs.

DLC--This paper contains a discussion of the problem of transmission distortions

in which it is assumed that the atmosphere is anisotropic and that horizontal ir- regularities in the dielectric constant are smaller than the vertical irregularities.

Formulas are given for determining the band width for the transmission of a message without distortions. The effect of antenna directivity on a possible bandwidth is also analyzed. --R.M.

E-425 Troitskii, V. N. , Otrazhenie ul'trakorotkikh voln ot sloistykh neodnorodnostei

troposfery. (Ultrashort wave reflection from stratified inhomogeneities of the

troposphere.) Radiotekhnika, Moscow, 11(1):7-16, Jan. 1956. English transl.

issued by Special Libraries Association Translation Center as its No. R-975.

20 p. Available John Crerar Library, Chicago. DLC--A theoretical treatment of

reflection of oblique incident ultrashort radio waves falling on stratified discontinuities in the troposphere and the determination of the coefficient of refraction

from various forms of superrefractive layers. The basic formula used is

Ae. 106

= ^- P -AT + 4800

A e

where P = pressure in mb, T = absolute temperature, e = absolute humidity.

(Met.Abs. 8J-149)-M.R.

E-426 Troitskii, V. N. , Rasprostranenie ul'trakorotkikh voln na bol'shikh rasstoianiiakh za predelami qorizonta . (Propagation of ultrashort waves far beyond the

horizon.) Radiotekhnika, Moscow, ll(5):3-20, May 1956. 13 figs. , 31 refs. , 32 eqs. DLC --After briefly reviewing theories of field strength in the far zone and the mechanism of tropospheric scatter, the author examines the problem of

extended range propagation of ultrashort waves on the assumption that this

phenomenon is due to dielectric constant irregularities which can be laminar as well as turbulent in nature. The mean value and stability of field strength

of a tropospheric wave are determined. The problem of fading and distortion

of waves in tropospheric scattering is briefly considered and experimental and

theoretical data are compared. A supplement deals with the problem of the

validity of the two-thirds law for tropospheric irregularities. The supplement

also contains a survey of experimental data on irregularities in the dielectric

constants obtained by different authors. --R. M.

E-427 Wait, J. R. , Currents excited on a conducting surface of large radius of curvature. IRE Transactions on Microwave Theory and Techniques, N. Y. , 4(3):143-

145, July 1956. Fig. , 5 refs. , 15 eqs. DBS--The nature of the electromagnetic

field of an antenna in the vicinity of a surface of large radius of curvature is

discussed. Assuming a spherical surface, the solution for a dipole source in

the form of the Watson residue series is transformed to a more rapidly converging series which is preferable at short distances. Using this result, numerical

data is presented in graphical form for the currents induced on the spherical

surface. The curves are applicable to both a stub and slot antenna mounted on

the conducting surface. --Author's abstract.
103

Wait, J. R. , Effect of the ground screen on the field radiated from a monopole.

IRE Transactions on Antennas and Propagation, N. Y. , 4(2):179-181, April 1956.

Fig. , table, foot-refs. , 10 eqs. DLC--In this brief note an attempt has been

made to show that quantitative results can be obtained which support the author's

earlier contention that the ground screen has only a small effect on the ground

wave field intensity for a special current on the antenna. (See ref. E-266)

-E.K.

Wait, J. R. , Mixed path ground wave propagation. Pt. 1. Short distances . U.S.

National Bureau of Standards, N. Y. , Journal of Research, 57(1):1-15, July 1956.

12 figs. , 10 refs. , 23 eqs. Also: J. R. Wait and J. Householder, Pt. 2. Large

distances. Ibid., 59(l):19-26, July 1959. 9 figs. , 10 refs. , 16 eqs. DLC--In

Pt. 1, an expression is derived for the mutual impedance between two short vertical antennas on a flat earth with a straight boundary separating two media of

differing electrical constants. After making some approximations that are valid

at low and medium frequencies and where the antennas are not near the boundary,

the integral formula for the field is evaluated for a wide range of parameters.

The numerical results computed in this paper are shown to be in reasonably good

agreement with experiment. Finally, the effect of the obliqueness of the boundary is considered by a refinement of the stationary phase evaluation of the integrals. In Pt. 2, the theoretical results for ground wave propagation over a mixed

path on a flat earth are generalized to a spherical earth. The problem is formulated in terms of the natural impedance between two vertical dipoles which are located on either side of the boundary separation. Extensive numerical results

are given in graphical form for a mixed land-sea path at frequencies of 10, 20,

50, 100 and 200 kilocycles per sec. --Authors' abstract.

Wait, J. R. , Radiation from a vertical antenna over a curved stratified ground.

U.S. National Bureau of Standards, Journal of Research, 56(4): 237-244, April

1956. 5 figs. , 13 refs. , 63 eqs. DLC--The problem of a radial electric dipole

outside a concentrically stratified spherical conductor, such as the Earth, is

formulated. The solution is facilitated by considering the analogous nonuniform

transmission line for the radial modes. The general result is then transformed

to a Watson type residue or azimuthal mode series, which reduces to the well

known result for the homogeneous Earth as a special case. Following a method

introduced recently by Brenner, the residue series is converted to an alternative

expansion, which is more suitable at short distances. The leading term of this

new expansion corresponds to the case of the transmitter and receiver over a plane stratified conducting earth. --Author's abstract.

Wait, J. R. , Transient fields of a vertical dipole over a homogeneous ground.

Canadian Journal of Physics, Ottawa, 34(l):27-35, Jan. 1956. 3 figs. , 9 refs.

DLC --Expressions are derived for the transient fields of a short vertical antenna,

situated on a smooth spherical conducting earth, and energized by a current

which is discontinuous in time. When the antenna current is a linear function

of time, the radiation field on a flat perfectly conducting earth is of step function form. The departure from the step shape of the field is shown to be due to the finite conductivity and dielectric constant of the ground, the induction and

static fields of the antenna, and curvature of the Earth. --Author's abstract.
104

E-432 Wait, J. R. and Howe, Herbert H. , Amplitude and phase curves for ground wave

propagation in the band 200 c/s to 500 kc/s. U.S. National Bureau of Standards,

Circular, No. 574. 17 p. May 21, 1956. 12 figs. , 2 tables, 13 refs. , 11 eqs.

DLC --After making several extensions to the formulas of Van der Pol and Bremmer,

field strength and phase values of the very low frequency ground wave from a

short vertical antenna are computed. The ground conductivity values chosen are

4, 0. 01, and 0. 001 mho per meter. The distances considered range from 1 to 1500 mi. --Authors' abstract.

E-433 Vysokovskii, D. M. , Nekotorye osobennosti rascheta radiorefraktsii . (Some

peculiarities in radio refractivity calculation. ) Radiotekhnika i Elektronika,

Moscow, l(3):274-276, 1956. 3 refs. , 14 eqs. DLC -Expressions of radio re- fraction, in the form of an integral and of a progression, and their applications

to computation problems are discussed. Conditions are determined, under which

refraction is independent of the form of the vertical distribution function of the

index of refraction. (Met.Abs. 8 J-183)--Transl. of author's abstract.

E-434 Wheelon, A. D. , Near field corrections to line-of-sight propagation. IRE Transactions on Antennas and Propagation, N. Y. , 4(3):322-329, July 1956. Fig. , 7 refs. , 53 eqs. --This study deals with the restrictions imposed on trans-horizontal propagation by the turbulent fluctuations of the troposphere's dielectric

constant. The field equation describing the propagation is developed and the

subsequent solutions are then used to calculate the rms phase error for an arbitrary path in the troposphere, including dimensional descriptions for the multipath, scattered amplitudes. The phase correlation between signals on two

parallel paths show the role of overlapping antenna beams. --W. N.

E-435 World Meteorological Organization, International Geophysical Year, 1957-1958,

Meteorological programme: general survey. Its WMO (Publication), No. 55,

IGY. 1, 1956. Ill p. forms. DWB, DLC -In a systematic review of the IGY,

its purposes, programs of investigations and observations, networks, communications, codes, data collection, etc. , a section is devoted to the observation

program for tropospheric propagation. The resolutions made in 1952, 1954 and

1956 by ICSU Joint Commission on Radio meteorology, URSI, etc. , the work

to be carried out by National Committees during IGY, and other details, are

outlined. The program calls for publication of radiosonde data up to 700 mb.

Captive balloon observations, refractometer measurements of refractive index,

humidity gradient measurements near cloud tops, study of humidity discontinuities and of diurnal, seasonal, geographic and cloud type variations in relative humidity gradient. (Met. Abs. 8 J-15D--M. R.

1957

E-436 Arenberg, A. G. , Rasprostranenie detsimetrovkvh i santimetrovykh voln.

(Propagation of decimeter and centimeter waves.) Izd-vo "Sovetskoe Radio"

Moscow, 1957. 303 p. Figs., tables, eqs., bibliog. p. 293-300. DLC

(TK6553. A64)--The author presents a survey of experimental and theoretical

work up to 1957. A separate chapter is devoted both to tropospheric scatter- ing and ionospheric scattering of ultrashort waves. The book contains an ex- tensive bibliography. --R. M.
105

E-437 Arvola, William A. (U. S. Navy Electron. Lab. , San Diego, Calif. ), Refractive

index profiles and associated synoptic patterns. American Meteorological

Society, Bulletin, 38(4):212-220, April 1957. 12 figs. , eqs. Also reprinted as U.S. Navy Electronics Laboratory, Research Report, NEL Report, No. 793,

May 23, 1957. DWB--A study is made of meteorological conditions associated

with synoptic patterns passing over the Middle West leading to super-refractive

index profiles. The signal strength for a 71. 75 Mc TV link in Illinois is related

to the refractive index profiles. (Met. Abs. 8 J- 152) --Author's abstract.

E-438 Basu, A. (Director General of Obs. .India), A brief note on the weather radar

studies undertaken in the India Meteorological Department . Weather Radar

Conference, 6th, Cambridge, Mass., March 26-28, 1957. p. 363-364. DWB

(M01. 81 R124pc)--Low power storm detection radar sets are in operation at New Delhi and Poona, and a long range set at Calcutta. Equipment is described

and their present and future use outlined. Studies of cloud and squall structure

during thunderstorms, cyclonic and monsoon storms and for studies of conditions

of superrefraction. --M. R.

E-439 Bauer, L.H.and Flood, W. A. , UHF forward scatter from lightning strokes . Institute of Radio Engineers, N. Y. , Proceedings, 45(12):1743, Dec. 1957.

Fig. , 3 refs. --Sample recordings of "spikes" rising from thunderstorms near the

midpoint of a propagation path are briefly discussed. This propagation is distinct from sferics, and may rather offer evidence of forward scatter from ionized

regions caused by cloud-to-cloud discharges. --W. N.

E-440 Baur, K. , Phasenverzerrung durch Bodeninhomogenitaten. (Phase distortion due

to surface inhomogeneities. ) NTZ: Nachrichtentechnische Zeitschrift, Brunswick, 10(8):385-389, Aug. 1957. 4 figs. , 11 refs. , 26 eqs. DLC--In preparatory work for the establishment of a direction finder station it is imperative to survey the immediate locality. Attention, in particular, should be paid to the

surface since it will affect the dielectric constant as a function of the local

variation of the surface conductivity. This fact causes a local phase deviation

from the normal value and contributes to a distorted result of the direction findings. Formulas are developed to permit a definition of the property of the sur- face, hence, the criteria for selection of a location suitable for a direction

finder station is given. --Transl. of author's abstract.

E-441 Bean, B. R. and Abbott, R. (both, Nat'l. Bur. of Stand. .Boulder, Colo.), Oxygen

and water vapor absorption of radio waves in the atmosphere. Geofisica Pura e Applicata, Rome, 37:127-144, 1957. 12 figs. , 4 tables, 22 refs. , 5 eqs. DLCCalculated values of the gaseous atmospheric absorption are presented for fre- quency range 100 to 50, 000 Mc at elevations above ground up to at least 130,000

ft, for average conditions during Feb. and Aug. at Bismarck, N. D. and Washington, D.C. Total radio path absorptions are presented for tropospheric forward

scatter communication links for distances of 100, 300 and 1000 mi. A correlation of total path absorption with the surface value of absolute humidity is developed, thus providing estimates of the range of absorption values in different

geographic areas. Maps of average absolute humidity for the world are presented. Previous work on rain absorption is then combined with the present study to provide estimates of the radio power loss due to absorption expected to be ex- ceeded 1% of the time. (Met. Abs. 8 J-153)--From authors' abstract.
106

E-442 Bean, B. R.and Cahoon, B. A. (Nat'l. Bureau of Stand. , Boulder, Colo.), A note on the climatic variation of absolute humidity. American Meteorological Society,

Bulletin, 38(7):395-398, Sept. 1957. 5 figs. , table, 8 refs. DWB--Maps of the

variation of absolute humidity over the U.S. are presented for the values exceeded 1, 50 and 99% of the time during the months of Feb. and Aug. Cumulative distributions of absolute humidity are presented for nine climatologically diverse

locations for the four seasons of the year. In addition, regression equations

have been derived to enable one to estimate the values of absolute humidity ex- ceeded 1 and 99% of the time at any location for which average values are available. Graphs show cumulative distributions for Tatoosh, Bismarck, Ely and

Miami. The charts are intended for use in radio refractive index or propagation

studies. (Met. Abs. 8 J-155)--From authors' abstract.

E-443 Bean, B.R., and Cahoon, B.A„, The use of surface weather observations to predict

the total atmospheric bending of radio rays at small elevation angles . Institute

of Radio Engineers, N. Y. , Proceedings, 45(11): 1545-1546, Nov. 1957. 3 figs.,

table, 8 refs. DLC--The purpose of this study is to evaluate any possible effects

of commonly observed marked departures of the actual refractive index profile

from the smoothed profiles so obtained. It is shown that the surface value of the

refractivity alone may be used to predict the total bending with useful accuracy even for elevation angles of arrival or departure as small as 10 milliradians.

»E. K.

E-444 Beard, C.I. and Katz, I., The dependence of microwave radio signal spectra on ocean roughness and wave spectra . IRE Transactions on Antennas and Propagation, N. Y. , 5(2):183-191, April 1957. 12 figs. , 2 tables, foot-refs. DBS--

This paper is an extension of previous work on reflection of microwaves from an ocean surface. Present analysis is based on data obtained in a one way X-band

propagation experiment performed across the Golden Gate, San Francisco. Two

paths of 9000 and 15,000 ft were used. To describe the ocean surface, wave

gages were mounted on a piling driven into the Golden Gate channel. Radio

signal spectra are found to be broader than the ocean wave spectra and the spectral breadth a function of ocean roughness. The important result of this analysis

is the establishment of a linear relationship between ocean roughness and the

spectral breadth of the radio signals. Ocean roughness is measured by the product of the standard deviation of the wave height and the grazing angle divided

by the radio wave length. Radio spectral breadths are determined by the fre- quencies at which each spectrum drops to the 0. 9, 0. 8, 0. 7, 0. 5, 0. 25 and 0. 1 power points. The breadth are then expressed as ratios of these frequencies to the frequency of the peak in the simultaneous ocean wave spectrum. The analysis now enables one to predict the approximate shape of the spectrum of the

radio signal received in a one way transmission path given only a knowledge of

the geometry, radio wavelength, ocean wave height, and the peak frequency in

the ocean spectrum. --Authors' abstract.

E-445 Beckmann, P. , A new approach to the problem of reflection from a rough surface.

Ceskoslovenska Akademie Ved, Acta technica, 2(4):311-355, 1957. 17 figs. , 41 refs. , eqs. DLC--This is an attempt to develop a statistical theory of the

scattering of a plane wave by a surface consisting of plane elements of random

slope. The profile of such a surface is given as a model of a stochastic process,

namely a Markoff chain with a finite number of states and discrete moments of

transition. The following assumption serve as the basis for the calculation of

the scattered field: a) Every element reflects the beam incident upon it with the

Fresnel reflection coefficient in the direction prescribed by geometrical optics;
107

b) The elementary waves reflected in the same direction are summed with respect

to their phases to form one resultant scattered wave in that direction. These as- sumptions are not strictly true but they afford a reasonable approximation. The

author derives the probability distribution of the amplitude of unit vectors with

random phases uniformly distributed between -a and +a for arbitrary values of a. (Rayleigh derived this distribution only for a = ). Each realization of a rough

surface with prescribed statistical properties will in general result in a different

scattering coefficient and the distribution of these individual values about the

mean value is the Rayleigh distribution. The author distinguishes two cases for scattering in the principle direction: a) distribution of the horizontal elements

with height is not uniform; b) distribution of the horizontal elements with height

is uniform. The theory is in agreement with accessible statistical measurements

of reflection coefficients of rough surfaces and, moreover, explains "polarization effect". The application of the theory to tropospheric propagation will be

the subject of further work. Here the author notes that when an irregular layer

moves through the region in the troposphere where radio waves are reflected

toward the receiver far beyond the horizon of the transmitter, this is equivalent

to different models of rough surfaces at different times. If the total time con- sidered is not too long, all these surfaces will have equal statistical properties.

The distribution of the scattering coefficient will of course be the same as that

of the received field strength. This field over short periods of time is Rayleigh

distribution. --R. M.

E-446 Berg, Eduard (Lwiro, Belg. Congo), Phasenverhaltnisse im Beuaunqsschatten

in geschichteter Troposphare . (Phase relationships in the diffraction shadow of a stratified troposphere.) Archiv der Elektrischen Ubertragung, Stuttgart, 11(9):

366-378, Sept. 1957. 10 figs. , 14 refs. , eqs. DLC. Transl. into English by

A.P.Barsis issued as U.S. National Bureau of Standards, NBS Translation, No.

5567, July 1958. 37 p. 10 figs. , 14 refs. , eqs. DWB (M10. 52 B493ph)--

The solution of the wave equation for a troposphere with over critical refraction

is given for a magnetic dipole with the aid of WHlTTACKER functions in a form

from which the solution for a homogeneous or nearly homogeneous atmosphere is

found as a special case by equating certain constants to zero. The obtained

series expansion of GREEN's function is converted with the aid of WATSON's

transformation. For the special case of infinite ground conductivity it is shown

that for tropospheric ducts it is requisite to have at least one real zero of the

denominator of the reflection coefficient supplying the residues in WATSON's

transformation. An approximation shows the dependence of the cutoff wave

length of the index of refraction and the height of the tropospheric duct. Besides,

the phase surfaces and their displacement at the ground are compared with conditions in a homogeneous atmosphere. (Met. Abs. 10. ll-255)--Author's abstract.

E-447 Beyers, Norman J. , Airborne refractometer installation . U.S. White Sands Signal

Corps Agency, Electromagnetic Radiation through the Atmosphere, Progress Report, No. 2, Jan. 11, 1957. 9 p. 5 figs. , ref. -The air-borne Type VI Microwave Refractometer developed by the Electrical Engineering Research Laboratory

at the University of Texas is briefly described and shown in photographs and diagrams. The instrument measures atmospheric index of refraction at a frequency

of approximately 9400 Mc, providing a continuous record of the index of refraction versus altitude. Its main parts are 1) the refractometer proper, 2) the power

supply, and 3) the recording meter. (Met. Abs. 8J-186)--G. T.
108

E-448 Booker, H. G. and Gordon, W. E. , The role of stratospheric scattering in radio

communication. Institute of Radio Engineers, N. Y. , Proceedings, 45(9):1223-

1227, Sept. 1957. 2 figs. , table, 9 refs. , 37 eqs. DLC--On the mixing-ingradient hypothesis of incoherent scattering of radio waves in a dry atmosphere,

the intensity of the irregularities in dielectric constant depends on the excess

of the temperature gradient above that appropriate to an adiabatic atmosphere.

In going from the upper troposphere to the stratosphere, there is a significant

increase in this gradient excess and consequently, a significant increase in

the intensity of irregularities in dielectric constant. The decrease in intensity

with increase of height measured by Crain in the troposphere does not, therefore, indicate reliably the intensity to be expected above the tropopause. Calculations have been made concerning the effect of stratospheric, as distinct

from tropospheric, scattering. Stratospheric scattering is expected to predominate over tropospheric scattering at ranges greater than about 600 km. At a range of 1000 km, the calculated transmission loss, due to stratospheric scattering, is a few decibels greater than is indicated by observations. The effect

of stratospheric scattering at a frequency of 108 Mc is such that the minimum

signal observed at this frequency over the path from Cedar Rapids, Iowa, to Sterling, Va. , could conceivably have been stratospheric origin, with ionospheric scattering being predominant at certain times, for example, during

SID's. (Met. Abs. 8 J-157) -Authors' abstract.

E-449 Boudouris, G. , Propagation tropospherique. (Tropospheric propagation. ) Paris,

Centre de Documentation Universitaire, 1957. 463 p. numerous figs. , eqs. , bibl. p. 459-463. Mimeo. --The author presents in this work a synthesis of present

knowledge concerning the propagation of radioelectric waves. The work is com- posed of 7 parts which deal successively with: 1. Propagation of plane waves;

2. Theorems and general notions. Specific waves; 3. and 4. Propagation over a level continent; 5. Propagation over the spherical earth; 6. Propagation over a nonhomogeneous world. Influence of irregularities of the ground and obstacles;

7. Propagation in real troposphere (nonhomogeneous). (Met. Abs. 10.5-28)

--A.V.

E-450 Bullington, K. , Radio propagation fundamentals . Bell System Technical Journal,

N.Y. , 36(3): 593-626, May 1957. 19 figs. , table, 34 refs. , 11 eqs. DLC--The

engineering of radio systems requires an estimate of the power loss between the

transmitter and the receiver. Such estimates are affected by many factors, in- cluding reflections, fading, refraction in the atmosphere, and diffraction over

the Earth's surface. In this paper, radio transmission theory and experiment in

all frequency bands of current interest are summarized. Ground wave and sky

wave transmission are included, and both line of sight and beyond horizon trans- mission are considered. The principal emphasis is placed on quantitative charts

that are useful for engineering purposes. --Author's abstract.

E-451 Chapman, J.H. ; Heikkila, W. J. and Hogarth, J. E. , A new technique for the

study of scatter propagation in the troposphere. Canadian Journal of Physics,

Ottawa, 35(8) -.823-830, Aug. 1957. 4 figs. , 16 refs. , 7 eqs. DLC--The power

spectrum of the fluctuations in received signal strength on a near optical UHF

circuit has been measured. The sidebands associated with these fluctuations can overlap the information carrying sidebands of a communication system.

When this happens, these sidebands must be taken into account in determining

the signal to noise ratio of the system. In other words, the fluctuations then

have the characteristics of noise and, therefore, they are called propagation

noise in the paper. Experiments at a carrier frequency of 500 Mc have shown
109

that the propagation noise power density usually varies with sideband frequency

2

f_ (measured from the carrier) as l/f_ , for f_ in the range 0. 1 to 10 c. p. s. Departures from this law have been observed in the regions near 0. 1 c. p. s. and 10

c. p. s. The measurement of the power spectrum directly offers several advantages over the conventional signal strength recording method, and these are discussed herein. --Authors' abstract.

E-452 Colloque International sur les Probl ernes d'Actualite dans la Propagation des

Ondes Radioelectriques, Paris, Sept. 17-21, 1956, Communications. L'Onde

Electrique, Paris, 37(362) :411-542, May 1957. And: Annates des Telecommunications, Paris, 12(5): 135-216, May 1957. Numerous figs. , tables, refs. , eqs. Review in Nature, London, 179(4555): 354-356, Feb. 16, 1957. DLC--

Eighty papers were presented at the International Symposium on Radio Wave

Propagation in Paris (Sept. 1956). Of these 27 are included in Qnde Electrique

(covering the fields of scatter propagation, theory, fluctuations, whistlers and

meteors) and 23 in Annates des Telecommunications (ionospheric propagation,

radio meteorology, effect of irregular surface, and antennas), while the remaining 30 are listed in both journals by title only. The following papers bear direct

relationship to the subject of this bibliography: Bean, B. R. (NBS, Boulder,

Colo.), Sur 1 'utilisation des observations meteorologigues courantes en propagation radioelectrique . (On the use of available meteorological data in radio

wave propagation), 1'Onde Electrique, p. 411-415. The use of meteorological

data in climatological studies of atmospheric refractivity is discussed with

special reference to work done by the U.S. National Bureau of Standards. It is

reported that 2& million complete sets .of data have been recorded on punched

cards, representing 10 yrs of surface observations made every 2 hrs at 54 sta- tions throughout the United States. A study of the global distribution of refractivity index has also been undertaken. World charts showing mean values of

surface refractivity in Feb. and in Aug. are presented. Beckmann, B. (Darmstadt, Germany), Observations de diffusion vers 1'arriere avec des siqnaux

telegraphigues(Observation of back scattering with telegraph signals), p. 416-

420. Describes new "annular" method developed in Germany. Carroll, Thomas

J. (M. I.T.Lincoln Lab. ), La propagation des ondes ultra-courtes au dela de

1 'horizon de Marconi a nos jours, (Propagation of ultrashort waves beyond the

horizon from Marconi to the present), p. 421-426. Short history including 38

references. Chisholm, James H. (M. I.T.Lincoln Lab. ), Recherches experi - mentales sur la diffusion angulaire et sur les possibilities d'utilisation de la

propagation tropospherigue pour les communications bien au dela de l'horizon.

(Experimental investigation of angular scattering and possibilities of the use of

tropospheric propagation for communication well beyond the horizon), p. 427-434.

Describes installation used at Lincoln Laboratories for measuring attenuation of

shortwave radio signals over long tropospheric paths (up to 830 mi). Clavier, P. (Compagnie Francaise Thomson, Houston), Calcul d'une liaison par diffusion

tropospherigue optimum du point de vue economique . (Calculation of optimum

tropospheric scatter communication from an economic point of view), p. 435-440.

Considers performance characteristics of the various components of scatter

propagation equipment and indicates best choice of apparatus for operation at reduced cost. Grain, CM. (Texas Univ. .Austin), Les refractometres et leurs

applications a la propagation radioelectrique et a d'autres probl ernes , (Refractometers and their applications to radio wave propagation and to other problems),

p. 441-443. Discusses airborne refractometers and results obtained with them

in the measurement of atmospheric refractivity variations with height and with

atmospheric conditions. Morrow, W. E. , Jr. (M. I. T.Lincoln Lab. ), Etude de

systemes de radiocommunication tropospherigue U.H.F. a lonque distance. (A

study of methods of tropospheric UHF radio communication over long distances),
110

p. 444.449. Includes schematic diagrams of equipment used in scatter propagation studies and graphical presentation of results. Wiesner, J. B. (M.I.T.)

and Pote, A.J. (Hyc on Eastern), Liaisons radioelectrigues au moven de la propagation par diffusion tropospherique. (Radio communication by means of tro- pospheric scatter propagation), p. 456-461. General review of tropospheric propagation beyond the horizon and of work conducted at Lincoln Laboratories.

Bochenek, K. (Warsaw, Poland), Sur certaines methodes d'analyse des rela - tions obtenues a l'aide de la methode W. K.B. . (On certain methods of analysis

of the relations obtained by means of the W. K. B. method), p. 462-464. Mathematical analysis of the possible application of geometrical optics to radio wave

propagation. Boudouris, Georges (Paris), Le probleme de propagation au des- sus de la terre spherique (terre et atmosphere homogenes) est-il definitivement

resolu? (Is a final solution available on the problem of propagation over a spherical earth (homogeneous earth and atmosphere)), p. 465-470. Reviews

classical and recent theories of radio wave propagation and concludes that

while the theoretical problems have been solved satisfactorily, no adequate

method has been developed for quick and complete field calculations. Carroll,

Thomas J. and Ring, R. M. (M. I. T.Lincoln Lab. ), Propagation des micro-ondes

dans la zone d'ombre a travers une couche d'air dont l'indice decroit de facon

monotone . Microwave propagation in the shadow zone through a layer of air

whose index decreases uniformly), p. 471-479. Treating the troposphere as a

dielectric layer stratified by gravity, the authors show that excessive field

strengths observed in the shadow zone can be explained by an atmospheric

wave guide effect without any additional effect of turbulence or unusual stratification. Fock, V.A. (Moscow, U.S.S.R.), Application des integrates com- plexes a certains problemes de diffraction. (Application of complex integrals

to certain problems of diffraction), p. 480-481. Author briefly sums up his own

work on the theory of radio wave propagation and refers to 13 papers published

by him since 1945. Goubau, Georg (Signal Corps Eng.Lab. ), Rapport entre

l'onde de surface et l'onde d'espace. (Relation between the ground wave and

the sky wave), p. 482-484. Considers theoretically the problem of separating

the field due to the ground wave from that due to the sky wave. Smyth, J. B. and Anderson, L.J. (San Diego, Calif.), L 'Importance du processus de re- flexion dans les communications au-dela de l'horizon, (Importance of reflection in communication beyond the horizon), p. 485-490. Reports results of airborne refractometer measurements throughout the U.S. and discusses mechanisms of radio wave reflection from tropospheric layers. Wong, Ming S. (Wright

Aeron. Develop. Center, Ohio), Methode des caustiques dans la propagation

tropospherique. (The method of caustic in tropospheric propagation), p. 491-494.

Shows that anomalies observed in air-to-air propagation can be explained by

stable horizontal layers, and anomalies of ground-to-air propagation by fragments of layers, and layers moving horizontally. Arsac, J. (Meudon Obs. , France) and Simon, J.C. (Paris), Problemes de fluctuation en propagation

lointaine . (Problems of fluctuation in long distance propagation), p. 495-497.

Discusses possibilities of an application of radio field measurement to the

study of atmospheric irregularities. Bremmer, H. (Philips Res. Lab. .Netherlands), Comparison des fluctuations de 1' amplitude et de la phase des champs

enqendres par diffusion (champs de turbulence) . (Comparison of the amplitude

and the phase variations of fields due to scattering (turbulence fields)), p. 498-

500. The statistical theories developed by RICE for the study of noise and by

BOOKER , RATCLIFFE and SHINN for the study of ionospheric propagation are extended and applied to the study of field strength and phase variations in

scatter propagation. Du Castel, F. (Lab. Nat. de Radioelectricite, France),

Divers types de fluctuations de champs tropospheriques et leur interpretation

physigue. (Different types of tropospheric field variations and their physical

interpretation), p. 501-506. Reports results of work done at the French
Ill

Telecommunications Research Center and presents graphs of field strength variations as functions of various meteorological and technical factors. Tukizi, Osamu

(Tokyo, Japan), Theorie du fading de scintillation en micro-ondes. (Theory of

scintillation fading of microwaves), p. 512-519. Suggests that scintillation fading

may be interpreted as being due to interference between direct and scattered waves.

Anastassiades, M. and Carapiperis, L. (Athens, Greece), Influence des facteurs

meteoroloqiques sur la propagation des hyperfrequences (Donnees sur la Mer Egt;e

du sud), (Effect of meteorological factors on UHF propagation (Data for the southern Aegean Sea)), Annales des Telecommunications, p. 177-180. From field measurements over a 120 km maritime path (Thera Heraklion) it is concluded that propagation conditions may be predicted correctly in simple weather situations such as

frequently prevail in the region investigated. Battaglia, A. (Pisa), Boudouris, G.

(Paris) and Gozzini, A. (Pisa), Sur l'indice de refraction de l'air humide en microondes . (Index of refraction of humid air for microwaves), p. 181-184. Reports

laboratory measurements made at the Institute of Physics at Pisa University, by

means of a spectrometer. Beckmann, Petr (Czechoslovakia), La reflection des

ondes VHF par les variations brusques d'humidite dans la troposphere . (Reflection

of VHF waves by abrupt humidity variations in the troposphere) , p. 50-52. Sharp

discontinuities of humidity at the boundaries of clouds show high correlation with

propagation beyond the horizon. Mevel, J. (Rennes, France), Etude sur l'inter- action de deux spheres voisines placees dans un champ electromagnetique . (Interaction of two adjacent spheres in an electromagnetic field), p. 186-188. Considers

the theory of diffraction of radio waves by cloud particles. Misme, Pierre (Paris),

Influence des discontinuites frontales sur la propagation des ondes decimetriques

et centimetriques . (Effect of frontal discontinuities on the propagation of decimeter and centimeter waves), p. 189-194. Analysis of field measurements over a 50 km maritime path during a frontal passage, and of measurements made during a shower. In addition to these papers printed in full, there are also several on

tropospheric propagation among those listed by title only. (Met. Abs. 8J-187)

--G.T.

E-453 Coroniti, S.C.and Gerson, N. C. , Scatter-field strengths and large ion concen- tration. Journal of Atmospheric and Terrestrial Physics, London, 10(4): 237-239,

1957. Fig. , 5 refs. DWB--Field strength well beyond horizon at 100-4000 Mc/s

varies only slightly with distance. To explain this, the concentration of large

ions N+ was compared with modified refractive N. From 2000-10, 000 ft N = 210

+ 0. 13N+. (Met. Abs. 10. 2-336)»C. E. P.B.

E-454 De, A.C.; Das, P. M. and Gangopadhayaya, M. , Super-refraction conditions at Dum Dum Airport. Indian Journal of Meteorology and Geophysics, Delhi, 8(4):

418-426, Oct. 1957. 5 figs. , table, 8 refs. DWB, DLC -Conditions for superrefraction have been studied at Dum Dum Airport (Calcutta) with a 3 cm radar.

There appears to exist some correspondence between the occurrence of ground

fog and mist on the one hand, and the appearance of super standard echoes on

the other. (Met. Abs. 8 J- 188) -Authors' abstract.

E-455 Dolukhanov, M.P. , Issledovaniia rasorostraneniia radiovoln vdol' poverkhnosti

Zemli v SSSR . (Investigations of radio wave propagation along the Earth's sur- face in the U.S. S. R. ) Radiotekhnika i Elektronika, Moscow, 2(11): 1344-1359,

Nov. 1957. 10 figs. , 43 refs. , 11 eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 2(11):39-61, 1957. DLC -After a historical review,

the author discusses briefly the cases of the propagation of radio waves by
112

diffraction, reflection, and scattering. The structure of the troposphere is also

briefly discussed. The final sections are devoted to the propagation of ultrashort

waves in tropospheric ducts and by tropospheric scattering. --R. M.

E-456 Egli, John J. , Radio propagation above 40 Mc over irregular terrain . Institute of

Radio Engineers, N. Y. , Proceedings, 45(10): 1383-1391, Oct. 1957. 15 figs. , 15 refs. , 5 eqs. DLC --Radio transmissions in the VHF and UHF frequency region over land areas always content with the irregularities of the terrain and the pres- ence thereon of dispersed quantities of trees, buildings, and other man made

structures, or wave propagation incumbrances. The determination of path attenuation is not easily satisfied by simple, curved, or plane earth calculations. However, quantitative wave propagation data are available in varying degrees which

take into account conditions experienced by fixed to fixed and fixed to moving

transmissions over irregular terrain. This available statistical wave propagation

information on terrain effects vs frequency, antenna height, polarization, and

distance is analyzed, expressed by empirical formulas, and presented in the form

of nomographs and correction curves amenable for use by the systems engineer.

—Author's abstract.

E-457 Fannin, B. M. and Jehn, K.H. , A study of radar elevation-angle errors due to atmospheric refraction. IRE Transactions on Antennas and Propagation, N. Y. , 5(l):71-77, Jan. 1957. 6 figs. , 2 tables, foot-refs. DBS-Refractive index

variations in the atmosphere cause errors in radar measurements. This paper

presents the results of a theoretical study of the elevation angle error due to the refraction of electromagnetic waves in the troposphere. The study is based

upon ray theory, using standard meteorological data reported by the U.S. Weather

Bureau for the surface and the standard pressure levels. Computed errors are tabulated for 34 monthly mean refractive index profiles selected as being representative of various type air masses for different seasons and latitudes. In order

to get an indication of the spread in propagation errors to be expected during a particular season for fixed locations, computations have been carried out based

on the 0300Z soundings for the odd days of Jan. (1950-1954) and July (1950-1953)

for nine U. S. locations. The diurnal influence is investigated by analyzing the

variations in surface refractive index for Jan. and July 1953, and also for nine

U. S. locations. --Authors' abstract.

E-458 Friis, H.T. ; Crawford, A.B. and Hogg, D.C. , A reflection theory for propagation beyond the horizon. Bell System Technical Journal, N. Y. , 36(3):627-644,

May 1957. 11 figs. , 10 refs. , 25 eqs. DLC --Propagation of short radio waves

beyond the horizon is discussed in terms of reflection from layers in the atmosphere formed by relatively sharp gradients of refractive' index. The atmosphere

is assumed to contain many such layers of limited dimensions with random position and orientation. On this basis, the dependence of the propagation on path

length, antenna size and wavelength is obtained. --Authors' abstract.

E-459 Furutsu, Koichi, Wave propagation over an irregular terrain. Pt. 1 . Japan. Radio

Research Laboratories, Journal, 4(16): 135-153, April 1957. Pt. 2. Ibid., 4(18):

349-392, Oct. 1957. Figs. , numerous eqs. DBS--A formula of field strength over an irregular terrain is obtained on the condition that both the radius and electrical

properties of the earth's surface discontinuously change several times along the

wave path. The formula is expressed in a unified form and is valid for the entire

range of frequencies. It is considered to be more general than those for mixed
113

paths of the homogeneous earth, since the latter can be derived from the former as special cases. The first paper of this series is mainly concerned with the

equation formulation and the derivation of the formula of field strength on the

general condition; the second paper is devoted to the derivation of supplemental

formulas for several cases of bad convergence of series of the obtained formula,

and also for several applications to diffraction by hills or mountains. --Author's

abstract.

Gossard, Earl E. (U. S. Navy Electronics Lab. ), Air-sea refractive index differ- ence charts for the Mediterranean-Southeast Asia areas. American Meteorological Society, Bulletin, 38(5): 274-278, May 1957. 8 figs. , 4 refs. Reprinted as U.S. Navy Electronics Laboratory, San Diego, Calif., NEL Research Report,

No. 794, May 23, 1957. DWB-Data for 350, 000 ship observations (on punched

cards at Asheville, N. C.) were used to calculate frequencies (for 5° squares)

in terms of median difference and standard deviation of sea-air refractive index

(Bs - Bb) for March-May, June-Aug. , Aug-Oct. and Nov. -Jan. for the Eastern

Mediterranean, Persian Gulf, Bay of Bengal and South China Sea. The data are presented on charts and the theory and techniques explained. (Met. Abs. 8 J- 160)

-M.R.

Gray, R.E., The refractive index of the atmosphere as a factor in tropospheric

propagation far beyond the horizon. IRE Convention Record, N. Y. , Pt. 1,

1957. p. 3-11. 10 figs. , 15 refs. DLC--In order to plan a tropospheric beyond

the horizon radio link, it is at present necessary to make transmission tests to establish the median path loss and to determine the magnitude and duration o! the path loss variations. Recent measurements indicate, however, that the re- lation existing between transmission loss and the refractive index of the atmosphere may enable estimates to be made, from climatic data alone, of the trans- mission characteristics of any particular path. Extreme values of transmission

loss are believed to be chiefly due to exceptional variations with height of the

refractive index, while the monthly median values of path loss have been found

to be a function of the average surface values of the refractive index of the at- mosphere on the transmission path. Curves are given showing the relation

found on various path between radio transmission loss and the refractive index.

--Author's abstract.

Gudmandsen, P. , A design chart for tropospheric scatter. Akademiet for de

Tekniske Videnskaber, Copenhagen (Danish Academy of Technical Sciences),

Microwave Laboratory Report, P 1625, Jan. 6, 1957. --The chart developed comprises frequencies 100 to 10, 000 Mc and distances 100 to 500 km and incorporates transmission power, antennae dimension, bandwidth, effective noise figure,

fading margin and signal-to-noise ratio. Its procedure is given along with experimental measurements for comparison showing that the transmission loss perhaps

is over estimated. Final conclusions necessitates further measurements. If the

minimum values at 400 - 800 Mc are not usable, higher, rather than lower fre- quencies are preferred. (Met. Abs. 8 J-161)--From author's abstract.

Hirai, Masaichi, Notes on phase incoherence in tropospheric propagation and

its effects on scattered field . Japan. Radio Research Laboratories, Journal,

4(17): 255-266, July 1957. 3 figs. , 6 refs. , 25 eqs. DBS-Assuming a Gaussian

form for the correlation function of the distribution of capacitivity in the atmosphere, the following is found: 1) Within the line-of-sight path, the time mean-
114

square value of the random phase difference at spaced points at the same distances

from the transmitter is roughly proportional to the scale of turbulence, to the propagation distance, and to the square of the frequency, but it is independent of the

separation between the spaced points, except in the case of an extremely short

propagation path and a close separation. 2) Beyond the horizon the effect of the

phase incoherence on the scattered field is considered to be negligible so far as

the time average value of the received power is concerned, within the range of

interest and on frequencies below UHF, inclusive. --Author's abstract.

E-464 Hirao, Kunio and Akita, Kin-Ichiro, A new type refractive index variometer.

Japan. Radio Research Laboratories, Tokyo, Journal, 4(18):423-437, Oct. 1957.

12 figs. , 8 refs. --Atmospheric refractive index variation in the frequency range

of radio waves can be expressed as the linear combination of both dry and wet

bulb temperature variations. A new type refractive index variometer based on

this principle, has been designed and constructed. In the present paper this

variometer is described in detail. Some observational data are shown with radio

meteorological considerations. --Authors' abstract.

E-465 IRE - URSI Symposium, April 30, May 1-3, 1956, Wash. , D. C. and Oct. 11-12,

1956, Berkeley, Calif. , Abstracts of papers. IRE Transactions on Antennas

and Propagation, N. Y. , 5(1):148-168, Jan. 1957. Foot-refs. DBS -In connection

with the first symposium, more than 100 papers, in connection with the second,

29 papers are summarized. Various aspects of radio wave propagation were discussed. Both symposia include papers treating the propagation of radio waves

in the troposphere. --E.K.

E-466 Johler, J. R. (Nat'l. Bur. of Stands. .Boulder, Colo. ), Propagation of the radio

frequency ground wave transient over a finitely conducting plane earth. Geofisica Pura e Applicata, Rome, 37:116-126, 1957. 6 figs. , 10 refs. , 22 eqs.

DLC--The theory of the propagation of a transient radio frequency ground wave

over a finitely conducting plane earth is presented for the particular case of the

NORTON surface wave by a consideration of a wave interrupted abruptly at one

point in time (t = O, T2) and a wave interrupted at one point in time followed by

an exponential decay. The first case is illustrated by several numerical examples of a cosine current wave applied to an electric dipole source. It is apparent

that the method of the inverse Laplace transform for the particular cases considered yields some simple mathematical formulas. (Met. Abs. 8 J-162)--From

author's abstract.

E-467 Kirby, R.S., Measurement of service area for television broadcasting . IRE

Transactions on Broadcast Transmission Systems, N. Y. , 7:23-30, Feb. 1957.

6 figs. , 5 refs. DBS --It is proposed that the present definition of television

service in terms of iso-probability contours, be abandoned. A new definition

of service area, first proposed by Norton and Gainen in 1950, is recommended

in its place. This provides a much more useful measure of service and makes

the estimating techniques more tractable. A method of estimating the service

area is described. This method consists of sampling the field strength at specified random locations along circular routes around the transmitter using

portable field strength measuring equipment and an antenna height of 30 ft. The estimate of the service area expressed in square miles is arrived at by a simple integration process based on the probability distributions of field

strength levels as a function of distance from the transmitter. --Author's abstract.
115

Kitchen, F.A.and Richmond, I.J. , Some characteristics of long distance scatter

transmission. Pt. 1. Transmission via ionospheric scatter. British Communications and Electronics, London, 4(2):74-78, Feb. 1957. 4 figs. , 14 refs. Also

Pt. 2. Transmission via tropospheric scatter. Ibid., 4(3):146-148, March 1957.

2 figs. , 15 refs. DLC--Some of the characteristics of ionospheric and tropospheric

scatter mechanisms of beyond the horizon transmission are reviewed. Pt. 1 is

concerned with the characteristics of ionospheric scatter propagation. Ionospheric

scatter communication systems were found to be relatively inflexible in terms of

operating frequency, and are suitable for operation between defined limits of distance. Pt. 2 is the treatment of tropospheric scatter communications systems,

which are extremely flexible from the point of view of choice of operating frequency.

For practical purposes, 400 mi may be taken as the upper limit of distance for trans- mission. The bandwidth capabilities of this mechanism are high, and may be possibly exploited for television relays on a point-to-point basis over moderate distances. --E. K.

Klinker, Ludwig, Aufschlusse uber den Fernausbreitunqsmechanismus im Meterwellenbereich durch tropospharische Driftmessunqen. (Distant propagation mechanism in the meter wave region by tropospheric drift measurements. ) Zeitschrift

fur Meteorologie, ll(2):43-49, Feb. 1957. 6 figs. , table, 11 refs. DLC--The

question is discussed whether propagation of ultrashort waves to great distances

is due to scattering by tropospheric turbulence elements or to partial reflection at free inversions. Fading at antennas 50-300 m apart shows systematic time differ- ences. In many cases the drift measurements coincided with wind discontinuities

at the lower limit of free inversions between 500 and 3000 m shown by upper air

ascents; examples are described. About two-thirds of the observations agree

with aerological data and support the occurrence of partial reflection. (Met. Abs.

8J-163)»C.E.P.B.

Klinker, L. , Experimentelle Untersuchungen zur Fraqe des Fernausbreitungsmechanismus im Meterwellenbereich. (Experimental investigations into the mechanism of the long range propagation in the meter wave region. ) Nachrichtentechnik, Berlin, 7(5):210-215, May 1957. 5 figs. , 7 tables, 20 refs. , 3 eqs. -Observations of USW fading over 50 km to 400 km distances were conducted in the period

of a year. It is shown that the fading ridges do not change significantly with the

length of paths. No dependency of the fading ridges on the average velocity of

tropospheric turbulence was found, whereas a close correlation was found with the

vertical components of movement of the tropospheric inhomogeneities. The diversity distance is dependent on the corresponding period of fading and fluctuates between 85 m to well beyond 400 m on a 180 km long path. During tropospheric drift

measurements it was by far the wind discontinuities present at the lower border of

the free inversions that were detected, These results are not interpretable in light

of the scattering theory. In the meter wave region it may well be that it is the partial reflection from layer inhomogeneities to transmission distances of not less

than 400 km which makes up the dominant mechanism of propagation. --N. T. G.

Klinker, L. , Weitere Eraebnisse von tropospharischen Driftbeobachtungen zur Fraqe des Fernausbreitunqsmechanismus im Meterwellenbereich. (Further results on tropospheric drift observations on the subject of radio propagation mechanism

in the meter wave range. ) Zeitschrift fdr Meteorologie, Berlin, 11(10/11) :339-344,

Oct. /Nov. 1957. 5 figs. , Stables, 5 refs. DWB, DLC -In order to investigate

the propagation conditions in the ultrashort wave region, 160 observations on tropospheric drift made with short waves were carried out at the Kuhlungsborn Observatory. Of these observations, 130 could be compared with simultaneous
116

aerological measurements at the Copenhagen-Castrup Station. The results of the

study indicate that the partial reflections in the meter wave region constitute the

exclusive propagation mechanism up to a distance of 500 km from the sender.

Ultrashort wave propagation observations prove to be a good aid in continuous

control by large geographic areas over the intensity of vertical transposition proc- esses in the lower troposphere, in particular of the ground layer, since the intensification or attenuation of strata inhomogeneities become immediately visible in

the intensity of the reflected field. Specific examples of drift observations ac- companied by aerological observations are presented. (Met. Abs. 13.4-164)

-I.L.D.

E-472 Knopfel, W. , Einige Vergleichsuntersuchungen der Wellenausbreitungsverhaltnisse in Band II und IV . (Some comparative investigations of propagation conditions in the II band and in the IV band. ) NTZ: Nachrichtentechnische Zeitschrift,

Brunswick, 10(5): 233-235, May 1957. 9 figs. , 3 refs. DLC--In order to secure

basic data pertinent in the planning of radio transmission networks, damping measurements in the IV band were conducted beyond diffractive ridges and locations.

The IV band result's show an average of 6 db position damping and of 12 db diffraction damping greater than those in the II band. A greater transmission density and a considerably pitched radiation output will produce adequate supply.

--N.T.G.

E-473 Kuhn, Udo, Ein Beitrag zur Kenntnis der Ausbreitungsbedingungen bei 1.3 GHz

nach Messuncren an einer Ubertragungsstrecke mit optischer Sicht. (Propagation

conditions at 1.3 GHz over an optical path.) BRF, Technische Mitteilungen,

Vol. 1, p. 4, 1957. (Unchecked) --The powerful field strength interference as observed in a year over a 82 km long Dezi relay line at 1.3 GHz featured daily and

annually variation. The results are compared with meteorological parameters

and show certain correlations between frequency of the fading and the intermixing of the lower atmosphere and the vapor pressure. --N. T. G.

E-474 Kuhn, U. , Einiahrige Feldstarkemessunqen im UKW-Rundfunkband in Kolberg

bei Berlin. (One year field strength measurements in the ultrashort wave radio

band at Kolberg near Berlin. ) Geofisica Pura e Applicata, Rome, 38:157-168,

1957. 13 figs. , 12 refs. German and English summaries. DLC--The results of

field strength measurements over some propagation paths in the frequency range

from 88-100 Mc are presented. On the average, the lowest field strength could

be observed in June and Dec. There was found a correlation between the temperature gradient at inversions and the field strength when using the average

values of field strength and the single values. The correlation coefficient between the field strength and the temperature gradient at the inversions is a function of the length of the propagation path. In the same way the amplitude of the

daily variation of field strength depends on the length of the propagation path;

the values being a maximum at a distance of 200 to 300 km. With a coefficient

of 0. 49 there was found a good correlation between the field strength and the

air pressure variation at ground level. As there also exists a correlation between the field strength and the temperature variations in the lower part of the

troposphere, a better correlation coefficient of 0. 58 was found when comparing

the field strength with the air pressure variation and the variation of the temperature at the 700 mb level. There are given some diagrams of the field

strength dependent upon the available air mass, the height of the 700 mb level

a. o. Some diagrams present the field strength variation with varying temperature gradient on inversions. As to the field strength variation with distance

there was found a curve which for more than 300 km is somewhat below this
117

curve that was measured by the Kuhlungsborn Meteorological Observatory. The

curve showed somewhat higher values compared with one curve which was published in a document of the U.S. presented at the CCIR Assembly in Warsaw in

1956. (Met. Abs. 9. 11-170) --Author's abstract.

E-475 Long, William G. and Weeks, Ray R. , Quadruple diversity tropospheric scatter

systems . IRE Transactions on Communications Systems, N. Y. , 5(3):8-19, Dec.

1957. 16 figs. , 12 refs. , 12 eqs. DLC-The need for highly reliable, multichannel systems for relatively long distances without repeating is pointed out.

It has been found that with the use of present operational equipment, with the

exception of high power bipolarized feed systems, quadruple diversity reception can be employed with only two parabolic reflectors per terminal. The quadruple diversity system utilizes the operational spare concept to advantage. This

system yields reliable multichannel communications for circuits well over 300 mi

in length. --E. K.

E-476 Mc Craken, Leslie G. , Ray theory vs normal mode theory in wave propagation

problems. IRE Transactions on Antennas and Propagation, N. Y. , 5(1): 137-140,

Jan. 1957. 2 figs. , 7 refs. , 24 eqs. DBS--A set of universal curves is pre- sented by which the approximate magnitude and phase of the reflection coefficient for vertical polarization can be determined at any grazing angle with relatively little computation. The approximation, which is almost always suffidiently accurate for engineering purposes, is excellent if the relative impedance of the reflecting medium is high and still quite good even if the impedance ratio is only moderately greater than unity. --Author's abstract.

E-477 Megaw, E.C.S., Fundamental radio scatter propagation theory. Institution of

Electrical Engineers, London, Proceedings, Pt.C, 104(6): 441 -455, Sept. 1957.

2 figs. , 5 tables, 29 refs. , 83 eqs. DLC--The text and the arrangement of the

extensive notes and analytical material left by the late author were prepared by

F. A. KITCHEN and M. A. JOHNSON. The detailed theoretical treatment of the

problem of beyond horizon scatter propagation includes a full analysis of the in- fluence of the geometry of the scatter volume on the received field strength. The

form for the spectral density of refractive index fluctuation, assumed congruent

with velocity fluctuation, is derived from the universal equilibrium theory of tur- bulence. It is here used to predict several aspects of stellar nature and radio

signal field strength fluctuation. Theoretical and experimental comparisons

support the theoretical form of the refractive index fluctuation spectrum. (Met.

Abs. 8 J- 164) -From author's abstract.

E-478 Merkulov, V.V., K teorii rasprostraneniia elektromaqnitnykh voln v sredakh

so sluchainvmi neodnorodnostiami pokazatelia prelomleniia. (Contribution to the theory of the propagation of electromagnetic waves in media with random

irregularities in the refractive index.) Zhurnal tekhnicheskoi fiziki, Moscow,

27(5): 1051-1055, May 1957. 5 refs. , 18 eqs. DLC-The author introduces a new characteristic of a field in a medium with random irregularities, the cor- relation function of the scattered field, which includes the relationship of field

fluctuations of amplitude and phase. By means of this function, a solution is found for the problem of the diffraction of electromagnetic waves with random

amplitude and phase at the aperture of the receiving apparatus. --R. M.
118

E-479 Millington, G. , Concept of the equivalent radius of the earth in tropospheric

propagation . Marconi Review, London, 20(126): 79-93, 1957. 5 figs. , 5 refs. , 73 eqs. DLC--The concept of the equivalent radius of the earth to take account

of a linear variation of refractive index with height in tropospheric refraction is

re-examined. It is shown that the transformation is not limited to nearly horizontal rays, but that essentially it reduces the curvature of the earth by that of

a ray traveling horizontally and the curvature of the rays by the amount required

to straighten them at whatever angle to the horizontal they may be going. The

results obtained geometrically in a previous paper for the angle of elevation at the refraction point, the optical path difference between the direct and indirect

rays and the divergence factor are derived by simple analysis, affording a useful check on the method. --Author's abstract.

E-480 Moyer, V.E. and Gerhardt, J. R., A survey of microwave refractive index analysis and forecasting techniques. Texas. Univ. Electrical Engineering Research

Laboratory, Report No. 6-18, Contract AF 19(604) -494, March 25, 1957. 16 p. 30 refs. DWB--The present knowledge, techniques, instrumentation and analysis in relation to the accuracy of forecasting both vertical and lateral refractive

index gradients are summarized and discussed in some detail. A balloon-borne

refractometer would seem to be the ideal instrument, particularly for the meteorologist. However, such an instrument remains to be invented. Author sums up

suggestions and recommendations pertinent to refractometry. (Met. Abs.

8J-165)--W. N.

E-481 Niwa, Shuntaro et al. , Results of experiments on the VHF overland propagation

beyond the radio horizon. Japan. Radio Research Laboratories, Journal, 4(16):

111-122, April 1957. 10 figs. , 3 tables. DBS--This paper gives the results of

experiments carried out from March to Aug. 1956 on VHF overland propagation

between Inubo and Kokubunji (123 km). The mean levels of field intensity, fading, etc. , are analyzed statistically and effects of frequencies used and location of receiving points are discussed. --Authors' abstract.

E-482 Onoue, Michio et al. , Microwave propagation over the sea beyond the line of

sight. Japan. Radio Research Laboratories, Journal, 4(18) -.395-406, Oct. 1957.

19 figs. , 5 refs. --Experiments on microwave propagation over the sea beyond

the line of sight were carried out on the frequency 9375 Mc/s along the Sea of

Kashima over a period of two years (1955-1957), the waves being transmitted at Inubo and received at Hiraiso Radio Wave Observatories. From the results so

far obtained, it is concluded that there is a qualitative correlation between

meteorological elements and the variation in field strength, and that the duct

contributes, in a large proportion, to the propagation beyond the line of sight

through the lower atmosphere along the coastline. --From authors' abstract.

E-483 Phillpot, H.R., Effects of meteorological conditions on ultra high frequency

radio transmission over two water paths in Australia. Australia. Bureau of

Meteorology, Meteorological Study, No. 11, July 1957. 27 p. 10 figs. , 6

tables, 18 refs. , eqs. DWB--The effects of atmospheric refraction on electromagnetic waves of various frequencies are discussed, and the basic theory of

the effect of variations in the atmospheric parameters on the refractive index of

the lower troposphere is reviewed. Results of earlier investigations made over sea paths in the United Kingdom, United States of America and New Zealand

are considered, and the current work in Australia for two links, at Mt. Bonython

Yorketown (South Australia) and Melbourne - Arthur's Seat, Victoria is outlined.
119

A technique is developed whereby it is possible to approximately assess the per- centage occurrence of fading which might be expected on any proposed over water

microwave link, the significant parameters being the temperature difference between the air and the underlying sea surface and the geostrophic wind speed.

(Met. Abs. 8J-189)--Author's abstract.

E-484 Plank, Vernon G. ; Cunningham, Robert M. and Campen, Charles F. , Jr. , (all,

G. R. D. , AFCRC), The refractive index structure of a cumulus boundary and

implications concerning radio wave reflection. Weather Radar Conference, 6th,

Cambridge, Mass., March 26-28, 1957, Proceedings, pub. 1957. p. 273-280.

5 figs. , 3 tables, 4 refs. , 3 eqs. DWB (M01. 81 R124pc) -Refractive index

measurements made during an aircraft pass through cumulus have been analyzed

for the details of index fluctuation at the cloud boundary. The microstructure is

described and an explanation suggested. A restrictive estimate of boundary

region reflectivity is obtained, using current theory. (Met. Abs. 9. 11-171)

--Authors' abstract.

E-485 Rogers, G.L. , An experimental verification of diffraction microscopy, using

radio waves. Journal of Atmospheric and Terrestrial Physics, ll(l):51-53, 1957.

6 refs. DWB--A DC -3 airplane was flown over 3 spaced radio receivers at 4000

and 8000 ft and fading of 125 m radio wavelength was recorded photographically.

The amplitude of the main wave fluctuated from 97-103% of undisturbed amplitude,

equivalent to a scatter of 0.09% of energy, but projected area of DC-3 is only

0. 028% of Fresnel half period zone. The 3 fold increase in effective projected area is attributed to conduction. (Met. Abs. 10. 2-178)--C. E. P. B.

E-486 Rogers, T. F. ; Ames, L.A. and Martin, E. J. , The possibility of extending air- ground UHF voice communications to distances far beyond the radio horizon. IRE Transactions on Communications Systems, 5(1): 106-121, March 1957. 9 figs.,

table, 6 refs. DLC --Certain of the results of a detailed research investigation of

220 Mcps tropospheric scatter field strengths at long distances and high altitudes

carried out at the Air Force Cambridge Research Center are reviewed in some detail. On the basis of the air-borne data obtained to date, supplemented by fading

statistics, reasonable initial estimates can be made of the UHF radio wave path

loss expected to obtain for various percentages of the time out to distances of

several hundreds of miles and up to altitudes of several tens of thousands of feet.

It is concluded, upon the basis of these path loss estimates, and initial air-borne

voice reception tests, that the scatter mode of propagation will permit the extension of reliable good quality air ground UHF voice communication to distances far beyond the radio horizon. --Authors' abstract.

E-487 Rowden, R. A. and Stark, J. W. (both, B. B. C. Research Dept. ), Long distance

propagation at 94. 35 Mc/s over the North Sea . Institution of Electrical Engineers,

London, Proceedings, Pt. B, 104(15):210-212, May 1957. 3 figs. , table. DLC--

A number of VHF (94. 35 Mc) propagation tests were made between Scheveningen,

Holland (52O06' 04°16'E) and 4 points in England, Scotland and the Shetlands

(123 to 591 mi) to determine over sea characteristics compared with previous over land propagation data. The over sea paths gave higher field strengths at the 1%

and 10% levels than the over land paths. In every case when relatively strong

signals were received it was found that anticyclones and inversions existed over

the North Sea. (Met. Abs. 8 J-167)--M. R.
120

E-488 Ryzko, Stanislaw, Radiokomunikacia na falach rozproszonych. (Radio communication using scattered waves. ) Tele-Radio, Warsaw, 2(12): 559-566, Dec. 1957.

7 figs. , 5 refs. DLC--A general survey of ionospheric and tropospheric scatter

propagation based on English language sources. Following a brief historical re- view, the phenomenon of scattering and the characteristics and use of scattered

waves are discussed. Some basic equipment is pictured and briefly described.

A final section covers the possibility of establishing communication systems

based on the reflection of signals from meteor trails. --R. M.

E-489 Sapporo District, Japan. Central Meteorological Observatory, On the lower temperature inversion layer and the curvature of microwave propagation at Sapporo.

Journal of Meteorological Research, Tokyo, 9(8):575-582, Aug. 1957. 5 figs.,

9 tables, 7 refs. , 7 eqs. DWB--The lower temperature inversion layer has an important role for the propagation of microwaves. In this report, some statistical

features of the inversion layer at Sapporo during 1952 and 1953 are examined,

that is: (1) height of the bottom of the layer, (2) height of the top of the layer,

(3) thickness of the layer, (4) temperature difference between the bottom and

the top of the layer, etc. Next, the curvature of microwave propagation in the

inversion layer is examined by use of radiosonde data. (Met. Abs. 9. 7-198)

—Author's abstract.

E-490 Saxton, J. A. , Scatter propagation and its application to television. Television

Society, London, Journal, 8(7):273-284, July-Sept. 1957. 6 figs. , 33 refs. -- The fundamental aspects of radio wave scattering at VHF in the ionosphere, and

at VHF and UHF in the troposphere are described; and a discussion is given of

the possible application of both mechanisms for communication purposes. Scatter transmission is useful only for point to point links; and the manner in which

the performance of these links depends on such parameters as frequency, bandwidth and aerial characteristics, is considered. Although ionospheric scattering

may be used at frequencies of 25 to 60 Mc/s over paths of 1000 to 2000 km, the

bandwidth capabilities are such that links operating in this manner are useful

primarily for telegraphy, and to some extent for telephony; and, without a revolution in existing techniques, there is very little likehood that television signals

will be relayed by this means. UHF tropospheric scatter links on the other hand,

although in general much shorter than ionospheric links, are capable of transmitting much greater bandwidth, and there appear to be reasonable prospects for their

ultimate use in relaying television over paths of a few hundred km as the technique

develops. --Author's abstract.

E-491 Saxton, J. A.; Kreielsheimer, K. S. and Luscombe, G. W. , Measurement of height

gain at meter wavelengths . Electronic and Radio Engineer, London, 34:89-95, 1957.

7 figs. , 12 refs. --A method has been derived, using lightweight, balloon-borne

equipment incorporating a system of telemetry, for the measurement of height gain

at meter wavelengths. The equipment has been designed primarily to operate at frequencies in the television B and I. Preliminary measurements made on the

sound channel of the Sutton Coldfield transmitter of the BBC (frequency 58. 25 Mc/s)

have shown that, under conditions of standard atmospheric refraction, the observed

height gain is very similar to that predicted by diffraction theory; but divergencies

from this theory occur with non-standard modes of propagation. —Authors' abstract.
121

Schunemann, R. , Uber den Ausbreitunqsmechanismus ultrakurzer Wellen bei

qrossen Entfernunqen. (Propagation mechanism of ultra short waves at great distances. ) Hochfrequenztechnik und Elektroakustik, Leipzig, 66(2):52-61, Sept.

1957. 6 figs. , 18 refs. , 11 eqs. DLC--It has been hitherto assumed that ultrashort wave propagation over great distances is dependent on atmospheric turbulence. The author shows theoretically that refractive index fluctuations and the

resulting partial reflections may also significantly contribute to the tropospheric

propagation mechanism. --G.T.

Schunemann, R. , Uber den Mechanismus der Ultrakurzwellenausbreitung ienseits

des Horizonts . (Mechanism of USW propagation beyond the horizon. ) Ilmenau.

Hochschule fur Elektrotechnik, Wissenschaftliche Zeitschrift, 3(l):59-62, 1957.

(Unchecked) --Field strengths up to 100 km distances are mainly controlled by re- fraction, whereas scattering is responsible for the daily variation and which was

experimentally evidenced through the 68 Mc transmissions over 76 km discussed

here. The results are presented in graphs. The tropospheric scattering is largely

responsible for the 100 - 800 km propagation from where ionospheric scattering

takes place up to about 2000 km. Experimental propagation curves for different

frequencies are accompanying the explanation of the tropospheric and ionospheric

scattering held in a simple non-mathematical language. The origin of scattering are largely due to atmospheric inhomogeneities in the form of layers and cells.

-N.T.G.

Silverman, Richard A. , Fading of radio waves scattered by dielectric turbulence . Journal of Applied Physics, N. Y. , 28(4): 506-511, April 1957. 2 figs. , numerous

foot -refs. , 21 eqs. DLC--The fading of radio waves scattered by dielectric turbulence is shown to be the result of two effects. The first is time variation of the

scattering eddies as seen in a coordinate system moving with the local wind velocity. The second is Doppler shifting produced by the con/ection of the scattering

eddies by the mean wind and by the macro-eddies. In the troposphere, the scatter- ing eddies lie in the inertial range of statistical turbulence theory. This makes it possible to find the envelope fading rate of the received scattered signal to within

a constant of proportionality by using dimensionality and similarity arguments. The

result is an expression for the fading rate as a function of carrier frequency which

departs significantly from that found with" scattering blob" models. (Met. Abs.

8 J-168) -Author's abstract.

Staras, H. , Antenna to medium coupling loss . IRE Transactions on Antennas

and Propagation, N. Y. , 5(2):228-231, April 1957. 4 figs. , 6 refs. , 10 eqs.

DBS—This paper presents an improved estimate of one of the more important systems parameters on a scatter circuit, namely, the antenna to medium coupling

loss. The work presented in this paper differs from the earlier work of Booker

and de Bettencourt, in that it permits evaluating the coupling loss even when nonconical, nonidentical antennas are used at either end of the scatter circuit, and

it also permits taking the anisotropy of atmospheric turbulence into account. An

important conclusion is reached that the coupling loss is not shared equally by

the two antennas (i. e. , transmitting and receiving) even if they are identical.

This is a phenomenon which should be fully appreciated by engineers designing

a scatter circuit or when measuring the coupling loss experimentally. --Author's

abstract.
122

E-496 Takahashi, Kozo, On the scattering of radio waves in the troposphere, strato - sphere and ionosphere. Japan. Radio Research Laboratories, Journal, 4(17):333-

340, July 1957. 5 figs. , 15 refs. , 23 eqs. DBS--This paper explains the mechanism of the scattering of radio waves in the troposphere, stratosphere and ionosphere, and introduces new formulas for the scattering of radio waves by the use

of the theory of partial reflection. The basic assumption is that the fluctuations

of refractive index are chaotic. --Author's abstract.

E-497 Tao, Kazuhiko, Meteorological influences on the hourly median field strength of

ultrashort waves in the diffraction region. Japan. Radio Research Laboratories,

Journal, 4(16) -.155-254, April 1957. Numerous figs. , tables, refs. , eqs. DBSAfter a brief historical review, a statistical investigation of seasonal variations

of the vertical gradient of refractive index, calculated from radiosonde observations at several stations in Japan, and of nocturnal inversions is reported.

Monthly charts of refractive index are included. The propagation theory of US

waves is dealt with and curves of field strength vs distance are shown for vari- ous values of vertical gradient of refractive index. The correlation between observed refractive index profiles and field strength variations is analyzed and

meteorological parameters involved are discussed in detail with the help of numer- ous sample records. Seasonal and diurnal variations of field strength are found to be closely associated with meteorological conditions. --G.T.

E-498 Tao, Kazuhiko, On the relationship between the scattering of radio waves and

the statistical theory of turbulence. Japan. Radio Research Laboratories, Journal,

4(15): 15-24, Jan. 1957. 20 refs. , 48 eqs. DBS--In Pt. 1 of this paper, the reduction of the scattering cross section derived semi-intuitively by VJLLARS and

WEISKOPF (1954, 1955) is discussed more vigorously from the mathematical model

of turbulent element. In Pt. 2, the scattering cross section is expressed in terms

of the energy spectrum of the turbulence which is equivalent to the TAYLOR - KARMAN correlation function whose physical meaning is clear from the viewpoint

of the statistical theory of turbulence. --Author's abstract.

E-499 Taumer, F. and Muller, K. , Die Ausbreitunq der Bodenwellen uber inhomoqenen

Unterqrund. (Propagation of ground waves over inhomogenous surfaces.) BRF

Technische Mitteilungen, 1(2):21, 1957. (Unchecked) --Exact analyses of the

ground wave propagation over a homogenous plain or spherical earth have been

made by several workers, but in practice this prerequisite is rarely met. Hence,

further development in relation to the practical application of empirical methods

for determination of the ground wave propagation over inhomogenous surfaces

have become imperative in the last years. The evaluation of the different methods

here discussed insures a technical interpretation of the area of radio coverage.

E-500 Telford, M. , Communications potentialities of tropospheric scatter. Point to point telecommunications, Chelmsford, England, Communications Division,

Marconi's Wireless Telegraph Co. , l(2):29-49, Feb. 1957. 9 figs. , photos.

DLC--After a short historical introduction, the various factors used in evaluating

the communications potentialities of tropospheric scatter are discussed. Particular attention is paid to methods of calculating path attenuation, the most reliable

of which appears to be that based on the angular distance concept. The calculation of received signal level and the more important parameters of FDM/FM scatter systems is then described. So called "optimum utilization" charts are introduced, useful for the quick assessment of system range, etc. Similar methods
123

are applied to the consideration of SSB amplitude modulation and a comparison is

made between the two types of modulation. Reference is made throughout to the

necessity for diversity operation and a section is devoted to diversity techniques.

The possibility of relaying television signals over tropospheric scatter circuits is

critically reviewed. --R. M.

Texas. Univ. Electrical Engineering Research Lab. , Measurements and analyses

of index of refraction of the atmosphere. Contract AF 19(604) -494, Report No.

6-19, Final Report, March 31, 1957. 16 p. Bibliog. of technical reports under

the contract, and papers published in journals or presented at meetings concerned

with the results of research activities under the Contract AF 19(604) -494, as well as several theses. DWB (M94. 7 T355r) --Development, installation and testing of

three air-borne refractometers as conducted from Aug. 1, 1952 through Feb. 28,

1957 is reviewed here. Two of the refractometers were designed for altitudes up

to 30, 000 ft and the third for altitudes up to 100, 000 ft. Accuracy of all refractometers was 1 N unit; the two former were direct electronically supplied, the latter

was direct or battery supplied for power. (Met. Abs. 8 J-169)--W. N.

Tolbert, C.W. and Straiton, A. W. , Attenuation and fluctuation of millimeter

radio waves. IRE Convention Record, N. Y. , Pt. 1, 1957. p. 12-18. 8 figs. , 10 refs. DLC--This paper contains a resume of the millimeter propagation measurements conducted by the Electrical Engineering Research Laboratory of the

Univ. of Texas. These measurements were made at wavelength of 8.6 millimeters

and 4.3 millimeters, and more recently and as yet unreported, at a wavelength of

3.35 millimeters. The 8.6 and 4.3 millimeter measurements were made at elevations of 0. 25 km and 4 km above sea level. The path length ranged from 3. 5 to 61 mi. The 3. 5 millimeter measurements were made at an elevation of 0. 25 km

over a path length of 7. 5 mi. The measured oxygen and water vapor attenuations

at the 3 millimeter wavelength are compared to theoretical attenuations. Spectra

of scintillations are shown and several of the refraction characteristics are noted.

A comparison of the propagation of the millimeter wavelength with that of 3. 2 cm

wavelengths is also made. --Authors' abstract.

Twersky, Victor, On scattering and reflection of electromagnetic waves by rough

surface. IRE Transactions on Antennas and Propagation, N. Y. , 5(l):81-90, Jan. 1957. 2 figs. , foot-refs. , 64 eqs. DBS—Simple approximations for the reflection

coefficients and differential scattering cross sections per unit area of a random

distribution of arbitrary protuberances on a ground plane are given in terms of the

scattering amplitude of an isolated protuberance, their average number in unit area, and the given incident wave. These functions take into account multiple

coherent scattering, and are mutually consistent in fulfilling the energy principle.

It is shown, in general, that if the horizon angle approaches zero, then the reflection coefficients approach unity linearly, and the horizontal/vertical back scatter- ing vanishes like the fourth/second power of the angle. General results are then

specialized to arbitrary hemispheres and circular semi-cylinder, and applied to limiting cases of perfect conductors with radii very small or very large compared

to wavelength. --Author's abstract.

Vvedenskii, B.A.and Arenberg, A. G. , Dal 'nee tronosfernoe rasprostranenie

ul'trakorotkikh voln. (Long distance tropospheric propagation of ultrashort waves.)

Radiotekhnika, Moscow, 12(1):3-11, Jan. 1957 and 12(2): 10-21, Feb. 1957. 14

figs. , 40 refs. , 5 eqs. Transl. into English in Radio Engineering, N. Y. , 12(1):

1-13 and 12(2): 10-25, 1957. DLC-This paper, in two parts, is essentially a survey
124

of literature on the subject of transhorizon tropospheric propagation of radio waves

up to 1956. The historical elaboration of the problem from the 1920's is traced,

and includes information on early experiments. Several pages are devoted to the

nature of fading. The problem of incoherent scattering is covered and the concept

of the scattering volume is explained. The final section of the paper deals with

the problems of coherent scattering, refraction, and diffraction of waves. --R. M.

E-505 Vvdenski, B. A. and Sokolov, A. V. , Issledovaniia troposfernogo rasprostraneniia

metrovykh, detsimetrovykh i s intimetrovykh radiovoln v SSSR . (Investigations

of tropospheric propagation of m, dm and cm radio waves in the U.S.S. R.) Radiotekhnika i Elektronika, Moscow, 2(11) -.1375-1389, Nov. 1957. Transl. into English in Radio Engineering and Electronics, N. Y. , 2(11):84-105, 1957. 2 figs. , 91 refs. , 2 eqs. --Scientific research work conducted in the U.S.S. R. since 1922

in connection with the propagation of ultrashort radio waves in the troposphere is

summarized. At the present time the problems under investigation consist of the

explanation of the general mechanism of ultrashort wave propagation to different

distances and the formation of a new theory, to allow engineering calculation of

long distance ultrashort wave lines of communication. --E. K.

E-506 Vysokovskii, D. M. , Geometricheskie kharakteristiki rasseianiia radiovoln na

turbulentnykh neodnorodnostiakh troposfery. (Geometrical characteristics of

radiowave scattering by the turbulent inhomogeneities of the troposphere.

)

Elektrosviaz", Moscow, 11(9):12-19, Sept. 1957. 2 figs. , 4 refs. , 43 eqs. DLC

--Exact and approximate formulas are derived for determining the dimensions of

the scatter volume and the angle of scatter. An expression is given for scatter- ed power in the form of an integral for the scatter volume. Dimensions of the

effective scatter volume with wide radiation patterns are determined on the basis

of investigations of the extreme of this integral. The problem of selecting antenna

dimensions for communication by scatter propagation is discussed, and the main

geometrical characteristics of the scatter volume with narrow radiation patterns

are given. --R. M.

E-507 Vysokovskii, D. M. , K vyvodu vyrazheniia secheniia rasseianiia v teorii diffuznogo rasprostraneniia UKV v troposfere. (Derivation of an expression for the

scattering cross section in the theory of tropospheric scattering of ultrashort

waves.) Radiotekhnika i Elektronika, Moscow, 2(5):659-660, May 1957. 2 refs. , 17 eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 2(5):

194-196, 1957. —The author presents a mathematical analysis of the notion of the

scattering cross section introduced by Booker and Gordon (1950) and elaborated by

Staras (1952). The author generalizes the cross section by a spectral function

which characterizes inhomogeneities in the dielectric constant and which is derived from the correlation function. It is shown that the scatter cross section is a function of scattering angle, not of wavelength. --R. M.

E-508 Vysokovskii, D. M. , Vliianie refraktsii na diffuznoe rasprostranenie ul'trakorotkikh voln v troposfere. (Effects of refraction on tropospheric scatter propagation

of ultrashort waves. ) Radiotekhnika, Moscow, 12(5):30-36, May 1957. 2 figs. , 2 refs. , 27 eqs. Transl. into English in Radio Engineering, N. Y. , 12(5):38-47,

1957. DLC —Approximate formulas are derived for the determination of such fac- tors of the effects of refraction on the diffuse propagation or forward scattering

of radio waves as decrease with the altitude of the scattering volume, change in

the angle of scattering and change in the value of the scattering volume. The
125

variation in power at the reception point in the presence of refraction is calculated.

The results obtained are compared with the data of the theory of scattering of radio

waves by turbulent inhomogeneities of the troposphere and with the experimental

data. --R.M.

E-509 Wait, James R. , A note on the propagation of the transient ground wave. Canadian Journal of Physics, Ottawa, 35(9): 1146-1151, Sept. 1957. 3 figs. , 9 refs. , 17 eqs. DWB, DLC --Calculations are presented for "the wave forms of the ground

wave field radiated from a transient electromagnetic source on the surface of the

earth. The variations of the source dipole moment are taken to be ramp, step,

and impulse functions, in turn. "The influence of the source on the radiative

waveform is illustrated graphically for the ramp, step and impulse function on a spherical earth. Time parameter t vs. actual time t' for various distances (200-

10, 000 km) are shown on a nomogram for a perfectly conducting earth and for propagation over sea. water. (Met. Abs. 10. 5-217)--M. R.

E-510 Wait, J. R. , Amplitude and phase of the low frequency ground wave near a coastline. U.S. National Bureau of Standards, Journal of Research, 58(5) -.237-242, May

1957. 3 figs. , 18 eqs. , foot-refs. DLC--A theoretical analysis is given for the

amplitude and the phase exchange of the ground wave, originating from a distant

transmitter on land, as it crosses a coastline. The land and sea are assumed to be smooth, and homogeneous with a sharp boundary of separation. Attention is

focussed on the effects that take place near the coastline when it is not permissible to employ arguments based on the principle of stationary phase. A limited

comparison is made with recent experimental work of Pressey, Ashwell, and

Fowler. --Author's abstract.

E-511 Wait, J. R. (Nat'l. Bu. of Stands, Boulder, Colo.), Propagation of a pulse across

a coast line . Institute of Radio Engineers, N. Y. , Proceedings, 45(11): 1550-1551,

Nov. 1957. 3 figs. , 3 refs. , 13 eqs. DLC —The transformation of the pulse shape

of the ground wave as it crosses a coast line for a source over the sea is briefly

discussed. Numerical results for various mixed paths previously obtained are generalized to the case of a transient or pulsed source. To simplify the problem,

the earth's curvature was neglected and the sea was assumed to be perfectly conducting. --E. K.

E-512 Wait, J. R. , The transient behavior of the electromagnetic ground wave on a spherical earth. IRE Transactions on Antennas and Propagation, N. Y. , 5(2):

198-202, April 1957. 5 figs. , 7 refs. , 20 eqs. DBS-Some calculations are pre- sented to show the nature of the transient ground wave radiated from an electric

dipole which is situated over a spherical earth. The moment of the dipole is con- sidered to vary with time in a linear manner. It is shown that the departure of

the leading edge of the radiation field from a step function form is a consequence

of diffraction and loss in the finitely conducting ground. --Author's abstract.

E-513 Wait, J. R. and Murphy, Anabeth, Influence of a ridge on the low frequency

ground wave. U.S. National Bureau of Standards, Journal of Research, 58(l):l-5,

Jan. 1957. 4 figs. , 6 refs. , 9 eqs. DLC -The problem of a plane wave incident on a semi-elliptical boss on an otherwise perfectly conducting flat ground plane

is considered. A solution in terms of elliptic wave functions is obtained. Numerical values of the field on the near and far side of this idealized ridge are given

for a base width of about two thirds of a wavelength and various ellipticity ratios.

--Authors' abstract.
126

E-514 Watt, A. D. and Maxwell, E.L. (both, Nat'l. Bureau of Standards, Boulder, Colo. ), Characteristics of atmospheric noise from 1 to 100 Kc . Institute of Radio Engineers, N. Y. , Proceedings, 45(6): 787-794, June 1957. 18 figs. , 10 foot-refs. , 3 eqs. DLC--The results of some preliminary statistical measurements of the en- velope of narrow band atmospheric noise are presented for a range of center fre- quencies from 1 to 100 kc. The variation of level and dynamic range, as a function of frequency, is examined and compared with results expected on the basis

of lightning discharge spectra, thunderstorm distribution, and propagation phen- omena. (Met. Abs. 9. 7-110) -Authors' abstract.

E-515 Wheelon, Albert D. (Ramo-Wooldridge Corp. , Los Angeles), Relation of radio

measurements to the spectrum of tropospheric dielectric fluctuation . Journal of

Applied Physics, N. Y. , 28(6): 684-693, June 1957. 10 figs. , 20 refs. , numerous

eqs. DLC--The size spectrum of isotropic fluctuations in the troposphere's dielectric constant is related to quantities measured by radio means. Two classes

of experiments are analyzed: (1) line-of-sight phase and amplitude instability,

and (2) refractometer measurements of dielectric fluctuations. This analysis is

independent of models for the dielectric fluctuations and provides a system from

which the spectrum can be estimated from experimental data. The measured quantities are expressed as weighted integrals of the spectrum, many of which may be

inverted to give the spectrum directly in terms of the data. Aerial smoothing by

the receivers and finite data sample effects are studied, in addition to the basic

propagation mechanisms. (Met. Abs. 8 J-173) --Author's abstract.

E-516 Wheelon, A. D. , Spectrum of turbulent fluctuations produced by convective mixing of gradients. Physical Review, 105(6): 1706-1710, March 15, 1957. Fig.,

199 refs. , 5 eqs. DLC --Isotropic fluctuations of a passive scalar iff produced by

turbulent convection are investigated. The source of irregularities is considered

to be the turbulent mixing of an established gradient of ty . The mixing velocity

field is described by HEISENBERG's spectrum for homogeneous, isotropic turbulence. Replacing the (self-mixing) transfer of energy down the spectrum by an

equivalent diffusion term, the local fluctuation spectrum becomes

s(k)= (7t/>)

2 -\ -r Hn— r 1

t? k

d [l+ (k/ks) 4

J4/3 U+ (k/ks)4/3_T

where ks is the viscosity cutoff wave number of the velocity field. In the inertial

range (k ^ks) this result agrees with spectrum deduced from purely dimensional

arguments. Support for the above spectrum comes from the scattering of radio

waves by dielectric fluctuations in the troposphere and ionosphere. (Met. Abs.

8J-172)-Author's abstract.

E-517 Wiesner, Jerome B. , New methods of radio transmission. Scientific American,

N.Y. , 196(1):46-51, Jan. 1957. 8 figs. (incl. photos). DWB, DLC -A non-technical, illustrated article on the fundamentals of ionospheric and tropospheric propagation, and especially on "scatter propagation" from the troposphere and ionosphere. The latter enables fairly long distance communication by means of 30 to 70 megacycle waves, but equipment and operations are costly. Line-of-sight

(30 mi) transmission is much cheaper but requires more installation and personnel,

and is not always possible in Arctic or at sea. Some of the giant antenna used

(e.g. at Cedar Rapids, Iowa and S. Dartmouth, Mass. ) are illustrated. (Met.

Abs. 8J-174)-M.R.
127

E-518 Wille, H. , Ergebnisse von Ausbreitungsmessungen an einer 15 GHz Strecke.

(Data on propagation measurements over a 15 GHz path.) Siemens Entwicklungsberichte, 20:226-227, Nov. 1957. (Unchecked)--The field strength of a 15 GHz

radio transmission over a 44 km path was measured over a period of 642 hr. The

transmitter and receiver set-up is described. Analysis of the frequency recordings

shows 84 hr with interference fading. Selective fading was observed at 50 MHz

when the field strength, as caused by non-selective fading, dropped 10 db below

the median value. The interference fading by multiple path propagation was distinctly separable into fading due to water vapor and that of rain. --N. T.G.

E-519 Wiltse, J.C.; Schlesinger, S.P.and Johnson, CM., Back-scattering characteristics of the sea in the region from 10 to 50 KMC . Institute of Radio Engineering,

N. Y. , Proceedings, 45(2) -.220-228, Feb. 1957. 11 figs. , 9 refs. , 7 eqs. DLC--

Measurements of radiation back scattering from the ocean have been made over

the frequency range from 10 to 50 kmc by means of several cw, Doppler, microwave systems operating simultaneously. The systems were mounted on the bow

of a ship and various antenna depression angles from 0° (horizontal) to 90° were

used. Data were obtained for vertical, horizontal, circular polarization, and for the cross polarized component of vertically polarized radiation. Horn antennas

of 20 db gain were used at all of the operating frequencies and, in addition,

higher and lower gain antennas were used at certain selected frequencies. Signals

recorded from a variety of sea conditions have been used to calculate the backscattering cross section per unit area, (7°, and these calculations indicate that

& ° is nearly constant with microwave frequency and increases as the antenna

depression angle is increased. The Doppler frequency characteristics of the re- turned signals have also been obtained from these measurements. A comparison

is made between the experimental results and the characteristics predicted from

simple scattering mechanisms. (Met. Abs. 8 J- 175) --Authors' abstract.

1958

E-520 Aksenov, V.I. , O rasseianii elektromagnitnykh voln na sinusoidal 'nykh i trokhoidal'nvkh poverkhnostiiakh s konechnoY provodimost'iu. (The scattering of

electromagnetic waves from sinusoidal and trochoidal surfaces of finite conductivity. ) Radiotekhnika i Elektronika, Moscow, 3(4):459-466, April 1958. Fig.,

6 refs. , 29 eqs. Transl. into English in Radio Engineering and Electronics, N. Y.,

3(4): 1-10, 1958. --The solution to the problem of scattering of electromagnetic

waves from a bounded section of a sinusoidal or trochoidal surface with finite

conductivity is obtained in the Kirchhoff approximation. The solution permits

the field to be calculated in the distant zone. A method is presented for the determination of the wave amplitudes in the scattering lobe maxima and an example

of the calculation of scattering of electromagnetic waves from a sinusoidal sur- face is considered. --Author's abstract.

E-521 Anastassiades, M. and Paraskevopoulos, P., Sur la variabilite des conditions

tropospheriques determined par les considerations radioelectriques. (Variability

of tropospheric conditions determined from radioelectric considerations. ) Academie des Sciences, Paris, Comptes Rendus, 246(26): 3656-3658, June 30, 1958.

3 refs. DLC--Thera Island is connected with the island of Crete through a hertzian

beam, operating on 1750 Mc/s with a purely maritime run of 120 km. Certain meteorological factors can have an effect on the intensity of the field picked up. The

examination of a large number of field recordings has established that the experimental curves of the field distribution did in fact agree with Raleigh's rule in the
128

case of periods superior to a certain limit. By using a special recorder, the authors were able to draw the experimental curves of the field distribution for timeperiods ranging as far as a fraction of one minute. Generally, the field distribution agrees entirely with Rayleigh's rule, but departs from this distribution in a very characteristic way as soon as time-periods shorter than 10 min are reached.

The deviation from this rule indicates unchanging tropospheric conditions, and in

this manner, starting from radioelectric determinations, one could determine the

longest period during which the troposphere presents unchanging characters.

(Met. Abs. 10. 8-19D-A.V.

E-522 Anderson, L.J. (Smyth Res. Associates, 3930 Fourth Ave. , San Diego, Calif.),

Tropospheric bending of radio waves. American Geophysical Union, Transactions,

39(2):208-212, April 1958. 7 figs. , table, 2 refs. , 8 eqs. DWB, DLC--A simple

and accurate method is presented for computing the refractive bending of radio

waves in the lower 100, 000 ft of the atmosphere. A given refractive index profile

is approximated by a series of straight lines (layers of constant gradient) and the

incremental bending computed for each layer. The method is applied to the 'standard' atmosphere, and total bending is plotted against the surface refractive index

for various vertical angles of arrival from to 1 radian. (Met. Abs. 10. 3-206)

--Author's abstract.

E-523 Angell, B.C.; Foot, J. B.L. and Lucas, W. J. , Propagation measurements at 3480 Mc/s over a 173 mi path. Institution of Electrical Engineers, London, Pro- ceedings, Pt. B, 105 (Supplement 8): 128-142, 1958. 25 figs. , 5 tables, 15 refs.

DN-RL--The paper presents an account of an experimental study of beyond-thehorizon radio scatter propagation at a frequency of 3480 Mc/s over a path of 173

statute miles between Start Point and Wembley. Details of the path and brief details of the transmitting, receiving and recording equipment are given. Propagation data, collected from May 1956 to April 1957, are presented. The perform- ance of the link is measured by the hourly median transmission loss, L, defined as the ratio, expressed in decibels, of the power transmitted to that received.

The diurnal and seasonal variations in L are discussed. The distribution of the

amplitude of the received signal within a period of an hour is used to investigate

the characteristic rapid fading of the scattered signal. Some attempt has been

made to associate variations in L with general trends in the weather. Experimental estimates of the aerial coupling loss are given and compared with various theoretical predictions. Preliminary measurements on double diversity, using aerials

which can be separated in the vertical direction by distances varying from 9 to 17

ft, are reported. The effects produced by aircraft flying through the beam are discussed, and a series of tests in which a naval aircraft flew both along and trans- versely across the transmission path are described. --Authors' abstract.

E-524 Asai, Juniichi; Fujikawa, Masatoshi; Tsuchiya, Kiyoma; Ishii, Takahiroo and

Kajikawa, Makota, Relation of the meteorological variables to the fading types

of VHF propagation over the sea. Japan. Radio Research Laboratories, Tokyo,

Review, 4(17): 266-276, Oct. 1958. 8 figs. , 4 tables, 6 refs. In Japanese;

English summary p. 266. DLC--The purpose of this paper is to describe the relation of certain meteorological variables, such as velocities and directions of

winds, states of the sky, etc., to the fading types of VHF. One way transmission tests were carried out from Jan. 1955 to Dec. 1957 over the Sea of Kashimanada, a distance of 77 km on the frequencies 60 and 150 Mc. Deductions

from the chi-square test are as follows: (1) considerable effects are apparent

under the following conditions of the surface wind velocity, especially on 150

Mc than on 60 Mc. When the velocity is over 8 m/sec, roller types decrease
129

and scintillation types increase; when below 8 m/sec, reverse is the case. (2)

The difference of air masses or weather charts is effectual and the seasonal variation is apparent, for example, roller types increase in summer, while scintillation

types increase in winter. (3) When the wind sits on the sea, roller types increase;

and on the land, scintillation types increase. (4) Interesting effects are observed

under certain states of the sky and with kinds of clouds. When lower clouds disappear and strati or stratocumuli appear, roller types increase markedly, scintillation types decreasing. When fractocumuli or fractonimbi appear, roller types

decrease and scintillation types increase. (Met. Abs. 14. 2-117)

E-525 Bauer, John R. and Meyer, James, H. , Microvariations of water vapor in the lower

troposphere with applications to long-range radio communications . American Geophysical Union, Transactions, 39(4) -.624 -631, Aug. 1958. 6 figs. , 14 refs. , 5

eqs. DWB, DLC --Variations of water vapor in the troposphere are calculated from

simultaneous airborne measurements of radio refractive index and temperature obtained respectively with a microwave refractometer and an aerograph employing a sensitive bead thermistor. The partial pressure of water vapor is calculated from

the well known equation

e(mb) = 2. 7 (n - 1)T

2 - 2. 1 X 10"4

PT

where n is the refractive index; T is temperature, °K; and P is total atmospheric

pressure mb. The method is applied to the investigation of the horizontal and ver- tical structure of water vapor associated with a thin inversion layer found near 9800 ft pressure altitude. Evidence is offered for the vertical stability and ab- sence of turbulent mixing of the air in the region of the inversion. When the re- flection coefficient of the observed layer at radio wavelengths of 600 and 72 cm

is computed at a range of 200 mi beyond the horizon, better than an order of magnitude agreement is obtained between the calculated and observed path losses at this range. --Authors' abstract.

E-526 Bean, B. R. (Radio Met. Sec. Nat'l. Bur. of Standards, Boulder, Colo.), First

meeting on radio climatology. Institute of Radio Engineers, Proceedings, 46(7):

1425-1426, July 1958. Eq. DWB, DLC--On Jan. 15, 1958, a meeting was held

at the Boulder Laboratories of the National Bureau of Standards, to determine

methods and standards for compilation of radio propagation indexes based on

meteorological data. The U.S. NBS, Air Defense Command, Army Signal Radio

Propagation Agency, Army Electronic Proving Ground, Navy Weather Research

Facility, and Naval Electronics Laboratory were represented. Agreement was

reached that constants K^ = 77. 6 and K2 = 4810 should be used in expressions

Ki ^2e RH

for refractivity in formula N=-^— P + ^ where P is station pressure

(mb), RH — relative humidity, e — vapor pressure in mb at absolute temperature

T (Kelvin). Also a listing should be made of past data for general use and these

and all punched cards at the N. W. R.C. (Asheville) should be sent to C. R.P.L.

(Boulder). Calculations of radio refractivity will be made from radiosonde data

at N. W. R.C. and five years of daily observations for Feb. , May, Aug. and Nov.

will be minimum for radio climatology of a place. (Met. Abs. 10. 9-7D--M. R.

E-527 Beckmann, Petr, Height errors in radar measurements due to propagation causes . Acta Technica, Prague, 3(6):471-488, 1958. 9 figs. , 2 tables, 7 refs. , 59 eqs.

Russian summary p. 487-488. DLC -Corrections to be used in target height
130

determinations on account of height distribution and variations of refractive index

are deduced analytically. Values for probability estimates of height error without

aerological measurements, and corrections when aerological measurements are available (pressure, temperature and humidity) are derived and presented in diagrams. --G. T.

E-528 Bigler, Stuart G. (Dept. of Oceanog. & Met. , A. & M. College), On the observation and application of angel echoes using the AN/CPS-9 radar. Weather Radar

Conference, 7th, Miami Beach, Florida, Nov. 17-20, 1958, Proceedings, issued

1958. Sec. D:22-30. 8 figs. , 8 refs. DWB (M01. 81 R124pc, 1958)--Echoes

from regions in the atmosphere where no reflecting of scattering sources could be

seen are described. Such echoes, commonly called angels, include the following

types, (1) echo lines caused by wind shifts associated with dry fronts, squall

lines, and air mass showers; (2) echoes indicating the presence of layers aloft;

(3) others which are uniform and diffuse, origin uncertain, and (4) fibrilliform

echoes presumably resulting from thermals. One or more of these echo types were photographed (but may have been observed more often) on 79% of the 37 radar

operating days between June 1 and July 23, 1958. Meteorological conditions during the observations are described. Application of the observation in short range

forecasting and in the study of certain atmospheric processes are proposed.

(Met. Abs. 11 H-15) -Author's abstract.

E-529 Bolgiano, R.,Jr. , The role of turbulent mixing on scatter propagation. IRE Transactions on Antennas and Propagation, N. Y. , 6(2):161-168, April 1958. 4 figs. , foot -refs. , eqs. throughout. DLC--The Villars-Weisskopf-Wheelon theory describing turbulent mixing of an established gradient is shown to contain a contradiction

which necessitates its being discarded. To fill the gap thus created, the theory

of isotropic mixing is extended to account for the presence of a gradient. The re- sults indicate that mixing in gradient cannot be employed to explain the wavelength dependence characteristic of much of the radio data. On the other hand,

it is shown that experimentally determined spectra of refractive index fluctuations

lend strong support to the mixing theory herein set forth. Hence, the conclusion

is reached that scatter theory, as it is currently based on atmospheric turbulence, can provide, at best, an incomplete description of transhorizon propagation.

--Author's abstract.

E-530 Bonavoglia, Luigi, Correlazione fra fenomeni meteoroloqici e propagazione oltre

l'orizzonte sul Mediterraneo. (Correlation between meteorological phenomena and

propagation beyond the horizon over the Mediterranean. ) Alta Frequenza, Milan,

27(6) :815-824, Dec. 1958. 5 figs. DBS (TK 6540. AS) -On the basis of results of

radio propagation experiments beyond the horizon over the open sea at different

altitudes between the island of Minorca and Sardinia, and of meteorological data on humidity, pressure and temperature obtained at different hours of the day at the observatories of Mahon, Carloforte and Elmas, variations of refractive index

at the surface and at different altitudes are determined and correlations are established between recession levels, gradients and refractive indices. --Transl. of

author's abstract.

E-531 Braham, Roscoe R. , Jr. ; Harrington, Edward L. and Hoffer, Thomas E. , Cloud

refractive index studies. Pt. 2. Use of distributions of A N vs. AS for estimating

mechanical turbulence. Chicago Univ. Dept. of Meteorology, Contract AF 19(604)-

1931, Technical Note, No. 17, Sept. 2, 1958. 18 p. 8 figs. , 2 refs. , eq.( Appendix: numerous tables. ) DWB--An analysis has been made of fine structure variations of refractive index in and around a group of about 70 cumulus clouds with a
131

view toward relating these variations to mechanical turbulence parameters. Fre- quency distributions of refractive index gradients were prepared for each level of

flight for clear air, cloud core and regions of transition at the cloud boundaries.

Similar distributions were prepared for refractive index increments. The latter

distributions, in the form of tables of N change vs. gradient size (AS), are pre- sented as an appendix. From these distributions a parameter analogous to the

"mixing length" of early turbulence theory was computed. This study shows that

eddies of the transition regions of cumulus clouds have dimensions of a few tens

of meters and are carried for distances of the order of 30-50 m before losing their

identity. Mixing lengths of clear air eddies are much larger than those of cloud

eddies, except, possibly, for those eddies in the uppermost parts of the clouds.

(Met. Abs. 10. 9-178) --Authors' abstract.

E-532 Braude, S.Ia. , O raspredelenii rasseivaiushchikh elementov pri rasprostranenii

radiovoln nad vzvolnovannoi poverkhnost'iu moria. (Distribution of scattering

elements in radio wave propagation over an agitated sea surface. ) U.S.S. R.

Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii,

Radiofizika, l(3):25-29, 1958. 2 figs. , 9 refs. , 2 eqs. DLC, NNC -A method

is proposed for the statistical study of the distribution of scatterers on the basis

of measurements of radio signals reflected from an agitated sea surface. The

method is similar to that used in radio astronomy for determining the distribution

of discrete radio sources. Experimental verification shows that the method pro- posed makes it possible to determine characteristics of the distribution of elements by which radio waves are scattered. --Transl. of author's abstract.

E-533 Braude, S.Ia. and Bass, F. G. , O vozmozhnosti opredeleniia funktsii raspredeleniia rasseivatele¥ na vzvolnovanno1!? poverkhnosti moria radiolokatsionnymi

metodami . (Feasibility of determining the distribution function of scatterers on an agitated sea surface using radar.) U.S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 1(3):161-162,

1958. DLC, NNC --The power of signals scattered by the sea may be written

X ^ ( R \ " A

\-=

J Where P and P is the power received by the radar

\ Ko / station at distances R and R . If Nand Nq are used to designate the total number

of sources which will scatter power P and PQ and more, then, according to the lit- erature, the following experimental relationship holds.

N

N„ 'O P—

The proposed method of determining the distribution function of scatterers is applicable when experimental data can be described

by the above equations and the antenna pattern of the locator is sufficiently nar- row that the distribution function does not depend on angular coordinates. --R. M.

E-534 Bremmer, H. , Applications of operational calculus to ground wave propagation.

particularly for long waves. IRE Transactions on Antennas and Propagation,

N. Y. , 6(3):267-272, July 1958. 11 refs. , 24 eqs. DLC--A11 results of the approximative diffraction theory dealing with the propagation of radio waves around

a smooth spherical earth (surrounded by a homogenous atmosphere) can be derived

from a one dimensional integral equation originally discussed by Hufford. This

equation can be solved in terms of operational calculus which leads, first of all, to the well known residue series. In this treatment the Sommerfeld theory for a
132

flat earth appears at once as a limiting case; moreover, analytic expressions for correction terms accounting for the finite value of earth's radius are easily determined. Finally, the equation in question can also be used for the extension to inhomogeneous soil conditions, without neglecting the earth's curvature. --Author's

abstract.

E-535 Buxton, A. J. and Felix, M.O. , The reduction of threshold by the use of frequency

compression. Institution of Electrical Engineers, London, Proceedings, Pt.B, 105

(Supplement 8): 117-121, 1958. 8 figs. , 4 refs. , 4 eqs. DN-RL--Any angle modulated system suffers from a threshold when the instantaneous noise vector becomes

equal to or larger than the carrier. This effect is a limiting factor in most f . m.

scatter systems, since the signal to any one receiver will fall below threshold for a far from negligible part of the time. The paper shows that the threshold level depends only on the combined bandwidth of the r. f. and i. f. circuits, and is unaffected by the existence of the frequency-compression loop. Thus, such a receiver

enables one to combine the large f. m. improvement of the wide deviation signal

with the low threshold of the narrow i. f. band. --Authors' abstract.

E-536 Cherenkova, Elena Lazarevna, Dal'nee rasprostranenie ul'trakorotkikh voln.

(Long distance propagation of ultrashort waves. ) Moscow. Gosudarstvennoe

Izdatel'stvo Literatury po Voprosam Sviazi i Radio, 1958. 42 p. 26 figs. DLC

(TK6553. C7)--A systematic survey, in popular form, of existing literature on long

distance propagation of ultrashort waves by tropospheric and ionospheric scattering. Attention is centered on the explanation of physical processes occurring in

this type of propagation and the results of experiments in this field. Requirements of equipment for ionospheric and tropospheric scatter links are covered.

--Author's abstract.

E-537 Chisholm, J.H. ; Rainville, L.P. ; Roche, J. F. and Root, H. G. , Measurements

of the bandwidth of radio waves propagated by the troposphere beyond the horizon.

IRE Transactions on Antennas and Propagation, N. Y. , 6(4):377-378, Oct. 1958.

3 figs. , foot-ref. DLC--A brief summary of experiments designed to investigate

the transmission characteristics as a function of time and frequency is presented.

The results of the analyses in the time and frequency domains are consistent and

both suggest that the multipath delays are less than predicted by the scattering

model used by S. O. Rice ,--E. K.

E-538 Denisov, N. G. , O rasprostranenii voln v plosko-sloistoi srede. soderzhashchel

statisticheskie neodnorodnosti. (Propagation of waves in a plane stratified medium

containing statistical inhomogeneities. ) U. S. S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, l(5/6):34-40,

1958. 5 refs. , 31 eqs. DLC--On the basis of the Einstein-Focker equation, the

propagation of waves in a medium containing regular and statistical inhomogeneities is analyzed. Fluctuations of the angle of reception, the angular spectrum

and the lateral correlation function of the wave field passing through the inhomogeneous layer are calculated. Intensity fluctuations are also computed. --Transl.

of author's abstract.
133

Dinger, H.E. ; Garner, W. E. ; Hamilton, D.H. , Jr. and Teachman, A.E. , Investigation of loner distance overwater tropospheric propagation at 400 mc. Institute of

Radio Engineers, Proceedings, 46(7): 1401-1410, July 1958. 15 figs. , foot-refs.

DWB, DLC--The results of an investigation of overwater tropospheric propagation

under both summer (July 1955) and winter (Feb. 1956) conditions are presented.

Transmissions were from a point on the south shore of Massachusetts, near New

Bedford, to a ship traveling along Great Circle courses to a maximum distance of

630 naut mi (724 statute mi) from the transmitter. A 10 kw, 385. 5 mc transmitter

feeding a 28 ft paraboloid antenna was used for the summer phase. For the winter

investigation, this same facility was used, supplemented by a 40 kw transmitter

feeding a 60 ft paraboloid for use at the greater distances. The frequency used

for the winter was 412. 85 mc. The receiving antenna aboard the ship was a 17 ft paraboloid for both series of tests. All antennas were horizontally polarized and

approximately 100 ft above sea level. The data obtained are presented to show

the median path loss vs. distance. The strip chart recordings of the received

signal levels are 'analyzed with respect to fading characteristics in an effort to separate out those transmissions which were enhanced by super refractive conditions. The fast fading signals, which were well represented by the Rayleigh distribution, were assumed to be unaffected by superrefractive conditions. The data

for the fast fading Rayleigh type signals appear to show a cyclic variation of the

attenuation rate with distance although there is no substantial deviation from a linear rate of between 0. 16 and 0. 18 db per nautical mile. (Met. Abs. 10. 4-163)

--Authors' abstract.

Dropkin, Herbert A. , Direct reading microwave phase meter. IRE National Convention Record, Pt. 1-6:57-63, 1958. 8 figs. , 9 refs. --An instrument for rapid

measurements of the phase properties of microwave networks is described and

discussed. Adjusted to a single frequency + 1° phase measurements are feasible.

The method is applicable for general use and at other microwave frequency ranges.

»W. N.

du Castel, Francois; Misme, Pierre and Voge, Jean, Reflexion d'une onde electromagnetigue par une couche d'atmosphere presentant une variation de l'indice de

refraction. (Reflection of an electromagnetic wave from an atmc spheric layer with

a variable refractive index.) Acad^mie des Sciences, Paris, Comptes Rendus,

246(12): 1838-1840, March 24, 1958. DLC--A general formulation of the reflection

coefficient, which may be interpreted as an increasing function of the atmosphere

thickness where great stability prevails, is presented. (Met. Abs. 10. 1-342)

--A.V.

du Castel, F. ; Misme, P. and Voge, Jean, Reflexions partielles dans l'atmosphere et propagation a grande distance. Pt. 1. Mesures meteorologiques . (Partial

reflections in the atmosphere and long range propagation. Pt. 1. Meteorological

measurements.) Annales des Telecommunications, Paris, 13(7/8):209-214,

July/Aug. 1958. Ibid. Pt. 2. Interpretation des mesures meteorologiques . (Interpretation of meteorological measurements. ) Ibid. 13(9/10) :265-270, Sept. /Oct. , 1958. 19 figs. , 11 refs. Also: du Castel, F. ; Misme, P. ; Spizzichino, A. and

Voge, J. , Supplement to Pt. 2, entitled: Variations des dimensions des feullets en fonction de l'altitude . (Layer size variations in function of altitude. ) Ibid.

15(l/2):48-50, Jan. /Feb. 1980. 2 tables, 2 refs. DLC -Theories of the electrical field beyond-the-horizon are reviewed in Pt. 1. Find each theory valid for a particular model atmosphere. Present results of measurements in France and

elsewhere. In Pt. 2, the authors study the two possible forms of flux in the

atmosphere: laminar and turbulent. The distinct studies of humidity mixing ratio

and of temperature lead to specify the turbulence conditions. It is, therefore,

concluded that the atmosphere is composed of two different families of layers: a stable one that corresponds to a laminar flux, and an unstable or turbulent one.
134

Each type of layer is separately examined with regard to the variation of the re- fractive index. Here the authors have investigated a certain number of parameters

relating to stable layers and to turbulent layers, but the horizontal extent range of

these layers has not been expressed in function of the altitude and only results

from measurements in the first kilometers of the atmosphere were given. In this

article the authors compute the variations of two proportional parameters: the one

having the same horizontal sizes and the layers, the other having the thickness

on the transition zone between the stable zone and the turbulent zone. The stable

layers possess comparable characteristics in the first kilometers of the atmosphere The irregularity characteristics of length and thickness are in the same range, and

all measurements made either by refractometer or by radar in the low stratosphere

are comparable to each other and permit to fix with a fair precision which parameters intervene in the numeric calculations of the partial reflections theory (See

refs. E-628, 785, 786, 772, and 715 for other parts) (Met. Abs. 14. 1-55) -A. V.

E-543 Eckart, Gottfried, Uber die Polarisationsdrehung elektrischer Wellen in inhomogenen isotropen Dielektriken unter besonderer Berucksichtigung der Troposphere . (Polarization shifts of electrical waves in inhomogeneous isotropic dielectric

media with particular attention to the troposphere. ) Zeitschrift ftfr Angewandte

Physik, Berlin, 10(8): 393-395, Aug. 1958. 2 refs. , 32 eqs. DLC -Polarization

shifts have been observed in ultrashort wave propagation where the path is entirely within the troposphere. Taking account of the known tropospheric inhomogeneities such shifts are explained on the basis of the Maxwell equations and

conditions are determined under which the shifts do not occur. --Transl. of author's

abstract.

E-544 Evdokimov, M. A. , Izuchenie rasseianiia radiovoln na troposfernykh neodnorodnostiiakh pokazatelia prelomleniia metodom radioastronomicheskikh izmerenh . (Investigation of radio wave scattering by tropospheric inhomogeneities of the re- fractive index using radioastronomical measurements. ) Radiotekhnika i Elektronika, Moscow, 3(12) -.1430-1440, Dec. 1958. 3 figs. , 4 tables, 8 refs. , 6 eqs.

Transl. into English in Radio Engineering and Electronics, N. Y. , 3(12):28-42,

1958. DLC --Results are presented of measurements on intensity of scattered

solar radiation on wavelength 3. 2 cm. The results obtained are compared with

theoretical estimates. --Author's abstract.

E-545 Felsenheld, R.A. ; Harstad, H. ; Jatlow, J.L. ; Levine, D. J. and Pollack, L. , Wide band ultrahigh frequency over-the-horizon equipment. Communication and

Electronics, N. Y. , No. 35:86-93, March 1958. 22 figs. , 2 tables, 5 refs. DLC--

Wide band over the horizon radio equipment in the 680 to 900 mc (megacycle) band

suitable for use in toll quality multichannel telephone or TV circuits is described.

The system comprises 60 foot parabolic antennas fed with dual polarization horns,

10 watt drivers, 10 kw amplifiers using 6 cavity klystrons, and receivers which

permit dual or quadruple diversity by combining the received signals at the IF (intermediate frequency). The over all 1 db bandwidth is 15 mc, and the time

delay distortion characteristics are suitable for interconnection with existing toll quality radio links. --Authors' abstract.

E-546 Flock, W.L. ; Mackey, R. C. and Hershberger, W. D. , Propagation at 36. 000

megacycles in the Los Angeles basin. California. Univ. at L. A. Dept. of Engineering, Report, 58-14, Feb. 1958. 55 p. 20 figs. , table, 13 refs. , 29 eqs.

DWB (M(051) C153pr)--Microwave propagation studies, at a frequency of approximately 36, 000 Mc, have been carried out in the Los Angeles basin. The basin is

characterized by the presence of the persistent, low level temperature inversion
135

of the eastern edge of the Pacific anticyclone, and this inversion is responsible

for the trapping of atmospheric pollutants. The index of refraction profile associated with the temperature inversion strongly influences microwave propagation.

An 11. 4 mi path from City Hall to the UCLA campus has been set up and used for obtaining experimental data. The system was completed in 1956 and data was obtained regularly in the fall of 1956. Operation on a smaller scale has been car- ried out since that time and the system is intact and available for further use. The

purpose of the investigation has been two fold. In the first place, it was anticipated that information would possibly be obtained about air pollutants and about

the atmospheric conditions associated with air pollution. Secondly, basic information concerning propagation characteristics and mechanisms, as influenced by

an inversion layer, was desired. No positive indication of the role of air pollutants has been obtained, but the report presents information concerning propagation characteristics and mechanisms. (Met. Abs. 13. 7-125)--Authors* abstract.

Fok, V.A. ; Vainshtein, L.A. and Belkina, M.G. , Rasprostranenie radiovoln po

prizemnomu troposfericheskomu volnovodu. (Radio wave propagation in a surface

tropospheric duct. ) Radiotekhnika i Elektronika, Moscow, 3(12): 1411-1429, Dec.

1958. 17 figs. , 4 tables, 7 refs. , 70 eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 3(12):l-27, 1958. DLC--The article is devoted to the theory of radiowave propagation between communication points in an inversion

layer (tropospheric duct) at the surface. A method for calculating the attenuation

factor in the presence of super refraction is developed. A number of concrete cases of propagation are calculated. More exact criteria are given determining

the existence or absence of long distance propagation as a function of the inversion layer properties and wavelength. --Authors' abstract.

Gough, M. V., Diurnal influences in tropospheric propagation. Marconi Review,

London, 21(131): 198-212, 1958. 8 figs. , 14 refs. DLC -The existence of diurnal

variations in the signal strength of very short waves has considerable scientific

interest. As is now well appreciated, the basic cause of these variations is the

nocturnal cooling of heated land by radiation when the sky is clear, which gives

rise during the night and early morning to pronounced atmospheric stratification near the ground. After a brief historical survey of observations of these effects,

this article appraises the results of 80 Mc/s signal strength recordings maintained

for 6 months over a 137 km nonoptical path in the Persian Gulf, where the phenomenon occurred to a noteworthy degree. Modified refractive index profiles derived

from selected upper air soundings made near the radio path have shown a clear

association between (a) very weak signals and an approximately standard atmosphere, and (b) very strong signals and the presence of pronounced elevated or ground based inversion layers. Measured and theoretical signal strengths are compared on the basis of a uniformly graded atmosphere, reflection at an idealized elevated inversion layer, and propagation within a duct as treated by

BOOKER. Finally, an analysis is made of M-profiles exhibiting the presence of

ground based ducts, which were found to be associated with high signal levels over the test path. It is shown that in 12 out of 19 instances, trapping of the

first transmission mode was taking place on a wavelength of 3. 75 m. These observations, made in exceptional climatic conditions, provide evidence of recur- rent nocturnal trapping on a wavelength which is perhaps longer than has hitherto

been considered possible. (Met. Abs. 12. 2-89) --Author's abstract.
136

E-549 Graf, Calvin R. (U. S. A. F. , San Antonio), Lightning enhancement of a VHF tropospheric scatter signal . Institute of Radio Engineers, Proceedings, 46(5, Pt. 1):915,

May 1958. Ref. DLC --Observations of enhancement of TV tropospheric scatter

signals each time lightning is seen are reported and details of the phenomenon and

accompanying circumstances are described. The observations were made in San

Antonio, Tex. , with video signals received from Houston and Midland, 200 and

300 mi distant. (Met. Abs. 14. 2-731) --G. T.

E-550 Grozier, A.L. , Captive Balloon refractovariometer. Review of Scientific Instru- ments, N. Y. , 29(4): 276-279, April 1958. 5 figs. , 3 refs. DLC--A system is described for measuring and recording rapid (3 cps) fluctuations of refractive index,

humidity (vapor pressure), and temperature using fast response thermistor beads.

The system utilizes wet and dry thermistors whose changes are fed into a simple

analog computer. The accuracy of the system is 1 part in 10* for refractive index,

about 0. 1 mbar for humidity and 0. 1°C for temperature. Measurements can be obtained to an altitude of 5000 ft above the measuring site, with an altitude accuracy

of 50 ft under optimum weather conditions. --Author's abstract.

E-551 Hirai, Masaichi; Fuji, Yoshihisa and Saito, Hiromu, An experimental investigation of the diffraction at VHF and UHF by mountain ridges. Japan. Radio Research

Laboratories, Journal, 5(21): 189-210, July 1958. 19 figs. , 8 tables, 10 refs, , 3

eqs. DBS—A diffraction propagation test over a distance of about 280 km between

Tokyo and Sado across the Mikuni Mountains was performed at the frequencies

159. 49 and 600. 00 Mc simultaneously. On the basis of results of these measurements, this paper discusses the temporal variations, spatial variations and trans- mission losses of the diffraction waves. --Authors' abstract.

E-552 Hirao, Kunio, Diurnal variation in intensity of fading of VHF wave. Japan. Radio

Research Laboratories, Journal, 5(20): 105-107, April 1958. Fig., 5 refs. DBS--

In the present paper, the ratio of the intensity of fading in the daytime to that in

the nighttime is discussed by means of the data of observations at several localities. The result of an analysis shows that the diurnal variation in received signal

becomes feasible when the cross point of the lines of sight drawn from both the

transmitter and receiver becomes higher than about 1 km above the surface.

--Author's abstract.

E-553 Isted, G. A. , Guglielmo Marconi and communication beyond the horizon: a short

historical note . Institution of Electrical Engineers, London, Proceedings, Pt. B,

105(Supplement 8):79-83, 1958. 5 figs. , 11 refs. DN-RL. Also same article in

Point to Point Communications, Essex, England, 2(2):5-17, Feb. 1958. DLC--

The paper describes experiments, carried out between 1928 and 1936 by Guglielmo

Marconi, which demonstrated that transmission beyond the horizon by means of

microwaves was practicable. Furthermore, the influence of tropospheric mechanisms on radiowave propagation was recognized by him at the time. --Author's

abstract.

E-554 Isted, G. A. , Marconi and tropospheric scatter. Marconi Review, London,

21(129):41-42, 1958. DLC --Several cases are cited from Marconi Review of 1933

where beyond-the-horizon reception of microwaves (30-600 mc) was achieved by

MARCONI in the Rome-Castel Gandolfo transmission route (mountains intervene)

from Sardinia to the Italian mainland (270 km or 8 times optical distance) and from

the steamer "Elettro" in the Mediterranean to Santa Margherita on the Italian
137

Riviera (250 km or 9 times optical distance). The assumption made by MARCONI

was that there was a stratification below the ionosphere (i. e. , the troposphere)

that would account for this nonoptical transmission. (Met. Abs. 12. 2-90)--M. R.

Johnson, M.A. , Review of tropospheric scatter propagation theory and its application to experiment. Institution of Electrical Engineers, London, Proceedings,

Pt. B, 105(Supplement 8): 165-176, 1958. 33 refs. , 48 eqs. DN-RL -A comprehensive review is made of published work on the theory of beyond horizon propagation of radio waves by means of oblique scattering from randomly distributed

irregularities of refractive index in the troposphere. A scattering theory is formulated which attempts to take as accurate account as possible of all effects likely

to be important in practice, consisting of some new results combined with the best

features of existing theories. Application of this theory to a variety of experimental results yields generally good agreement. Possible causes of some discrepancies, and the likely relative importance of scattering and certain other long distance propagation mechanisms, are discussed. (Author's abstract.

Jones, R.F. (Met. Office, London), Radar echoes from atmospheric inhomoqeneities. Royal Meteorological Society, Quarterly Journal, 84(362) -.437-442, Oct.

1958. 2 tables, 9 refs. , 14 eqs. DWB, DLC--The possibility that radar echoes

from atmospheric inhomogeneities are the explanation of echoes received in conditions which made it certain they are not received from precipitation elements

(" angel " echoes) is examined quantitatively. It is shown that such an explanation

is theoretically possible but that the required refractive index changes are large,

involving changes of a few mb in vapor, pressure and/or a few degrees C in temperature in a distance of about 25 cm. Reflection of the main or side lobe energy

at a limited quasi-horizontal surface is shown to give the most likely meteorological explanation, but the inability to measure changes of refractive index in the

free atmosphere to the required accuracy prevents positive confirmation. (Met.

Abs. 10. 8-132) -Author's abstract.

Josephson, B. and Carlson, G. , Distance dependence, fading characteristics and

pulse distortion of 3000 Mc trans-horizon signals . IRE Transactions on Antennas

and Propagation, N. Y. , 6(2):173-175, April 1958. 6 figs. DLC -Statistical analysis of signal recordings at 10 cm wavelength has given the following results. The

distance dependence of the half hour signal median Fm over a sea path corresponds

to a scattering parameter which is approximately inversely proportional to the

height. Between Fm and the surface value of M a correlation coefficient of 0. 62

is found, and between Fm and the dew point 0. 55. A unit increase of M seems to be followed by a signal increase between the limits 0. 3 and 0. 8 db. The fading

range, as defined between the 10% and 90% of time levels, is 12-14 db, and the

fading frequency mostly about 2 c/s for a 300 km path. Over a 260 km land path

the pulse broadening was normally 0. 1-0. 2 which corresponds to a scattering

parameter varying inversely as the first to second power of the height. A severe pulse distortion caused by selective fading is found to be very common. Some

other propagation characteristics are also discussed. --Authors' abstract.

Josephson, B. and Eklund, F. , Some microwave propagation experiences from a

just below horizon path. IRE Transactions on Antennas and Propagation, N. Y. , 6(2):176-178, April 1958. 5 figs. , 2 refs. DLC--Based on comparisons between

field strength records at 2300 Mc and simultaneously measured M curves, it is

concluded that the most important propagation disturbances on the test path are caused by reflection from discontinuities in the refractive index profile. The
138

occurrence probability for such discontinuities is shown to have marked seasonal

and diurnal period with a maximum in the summer and around sunrise. --Authors'

abstract.

E-559 Jowett, J. K.S., The measurement and prediction of VHF tropospheric field

strengths at distances beyond the horizon. Institution of Electrical Engineers,

London, Proceedings, Pt. B, 105(Supplement 8):91-96, 1958. 7 figs. , table, 16

refs. DN-RL--Following a brief historical review of theoretical and practical deductions concerning the characteristics of VHF tropospheric propagation beyond

the horizon, an account is given of a series of measurements made since 1948 by

the Post Office at receiving sites within the United Kingdom. Particular attention

is given to the concept of angular distance and to the effect of path profile on the

median levels of field strength, as well as on the range of fading observed. Simple transmission laws deduced from the observed data enable empirical curves of

field strength versus distance to be drawn for various percentages of the time.

--Author's abstract.

E-560 Joy, W. R.R., Radio propagation far beyond the horizon at about 3-2 cm wavelength. Institution of Electrical Engineers, London, Proceedings, Pt. B, 105

(Supplement 8): 158-164, 1958. 5 figs. , 2 tables, 6 refs. DN-RL--A series of

measurements on transmissions of 3. 2 cm wavelength at ranges far beyond the

radio horizon has been made over various paths, at arbitrary periods of time.

These have established the existence of an essentially permanent extra-diffraction signal field. While its level does not change appreciably with time, the

character of this signal can vary from that typical of a scattering process to that

due to a coherent mode of propagation. Further, although the observed signal

attenuation rate with distance is similar to that expected for a scattered field,

the average level is found to be some 10-15 db below that predicted from theory.

There appear to be factors affecting the long range propagation of 3. 2 cm waves

through the lower atmosphere which are incompletely understood. Although no

extensive analysis of meteorological conditions has been made, there is some

evidence to show that the existence of extensive well pronounced anticyclonic

systems results in poor propagation conditions for the extra diffraction signals.

--Author's abstract.

E-561 Joy, W. R.R., The long range propagation of radio waves at 10 cm wavelength. Institution of Electrical Engineers, London, Proceedings, Pt. B, 105(Supplement

8):153-157, 1958. 11 figs. , 2 tables, 7 refs. DN-RL- -A survey is presented of

the results obtained in a series of short term experiments on the propagation of

10 cm radiation over clear sea paths to distances well beyond the diffraction

region, under a variety of weather conditions. Very slowly attenuated signals

have been received consistently, under normal atmospheric conditions, from an

initial threshold beyond the horizon when the diffracted signal is some 60 db

below the corresponding free space level. Analysis of the amplitude distributions of some of the received signals confirms that propagation to ranges in the

extra diffraction region was due to a scattering process. --Author's abstract.

E-562 Kalinin, Iu. K. , K voprosu o difraktsii radiovoln nad neodnorodnoi sfericheskol

poverkhnost'iu Zemli . (The question of diffraction of radio waves over an inhomogeneous spherical Earth surface.) Radiotekhnika i Elektronika, Moscow, 3(10):

1274-1279, Oct. 1958. 4 refs. , 17 eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 3(10): 77-85. DLC--A formula is obtained for the
139

attenuation function when the path consists of n sections. A particular case is

considered of paths consisting of a large number of sections and paths in which

one of the sections is small. The formula for the attenuation function is generalized to the case of continuously varying path parameters. --Author's abstract.

E-563 Kalinin, Iu. K. and Feinberg, E.L. , Rasprostranenie zemnoi volny nad neodnorodnoi sfericheskoi poverkhnost'iu Zemli . (Ground wave propagation over the surface

of an inhomogeneous spherical earth.) Radiotekhnika i Elektronika, Moscow,

3(9): 1122-1132, Sept. 1958. 5 figs. , 8 refs. , 24 eqs. Transl. into English in

Radio Engineering and Electronics, N. Y. , 3(9):25-41, 1958. DLC -The theory of

ground wave propagation over an inhomogeneous path is generalized to the case

of a spherical Earth. Formulas for the attenuation function (for beyond the horizon

reception) when the path consists of 2 or 3 homogeneous sections, are given.

Coastal refraction is also considered. --Authors' abstract.

E-564 Kennaugh, E. M. and Cosgriff, R.L. , The use of impulse response in electromag - netic scattering problems . IRE National Convention Record, N. Y. , Pt. 1-6:72-77,

1958. 7 figs. , 2 refs. --Nearly exact solution to electromagnetic scattering problems for any source frequency by an approximation to the impulse response of the

scatterer is illustrated for several types of scatterers. Comparison of this novel

method described is made with results as obtained by standard methods. --W. N.

E-565 Kitchen, F.A. and Johnson, M.A. (both, Royal Naval Scientific Service, London),

Role of turbulent scattering in long distance radio propagation at Metre wave-lengths.

Nature, London, 182(4631): 302-304, Aug. 2, 1958. Fig., 7 refs. DWB-A report on experiments apparently confirming the theoretical prediction of the mechanism of

long distance propagation of short waves as a function of scattering of the randomly

distributed irregularities of the refractive index associated with atmospheric turbulence. A frequency of 203. 5 Mc/s was used in the experiments conducted by the

Admiralty Signal and Radar Establishment, Nov. and Dec. 1957, in the English Channel. A ship-borne transmitter against a shore based receiver near Portsmouth gave

the practical confirmation of the presence of the phenomenon at meter wavelengths.

(Met. Abs. 13. 9-111)-- W.N.

E-566 Kitchen, F. A. ; Richards, E. G. and Richmond, I.J. , Some investigations of meterwave radio propagation in trans-horizon region. Institution of Electrical Engineers,

London, Proceedings, Pt.B, 105(Supplement 8): 106-116, 1958. 12 figs. , table,

21 refs. DN-RL --Investigations have been made of the characteristics of metric

radio transmissions in the trans-horizon region, at ranges up to 400 nautical miles.

These indicate the essentially continuous existence of troposphere supported signal

components in this region, although their detailed characteristics are subject to var- iations. Under particular meteorological conditions, such as the formation of an

elevated inversion layer, an additional propagation mode is present, leading to a composite signal at intermediate ranges. --Authors abstract.

E-567 Malkowski, G. , Kleinraumioe Suoerrefraktionserscheinungen hinter einem abziehenden Gewitter. (Small scale superrefraction phenomena behind a moving thunderstorm. ) Meteorologische Rundschau, Berlin, 11(5): 141-145, Sept. /Oct. 1958. 13

figs. , table, 3 refs. , 4 eqs. DWB, DLC --The mechanism of superrefraction of cm

waves is discussed with the aid of a formula expressing the refraction index, and

three principal types of vertical distribution of the refractive index are established.

These are as follows: Type I in which the refraction index (N) increases with
140

elevation in the 0-3 km layer above the ground (dN/dh > 0); Type II is characterized by N being constant with altitude (dN/dh 0) and in Type III, N decreases

with altitude (dN/dh =0). A case of small scale superrefraction arising behind

a passing thunderstorm observed with the Berlin radarscope during the evening of

May 8, 1958, is presented. With the aid of radar pictures the author describes

the propagation of the radar echo. After passage of the echo ENE, numerous

brightly illuminated ground targets appeared. These additional ground echoes became visible only within a 35 km wide strip traversed by the storm; in the other zones of the radar area the propagation toward ground targets remained normal.

Two explanations are given for the brief improvement in propagation. One explanation suggests that the cause is the heavy rainfall released by the storm; as a re- sult of rain penetration into the uppermost ground layers (in the case of 3 cm radar

a ground layer of only several centimeters thickness suffices) the reflection capacity of the ground is raised. The change of reflection capacity caused by the rain

is computed by means of the Fresnel equation. The other explanation is based

upon the assumption that behind a thunderstorm there occur processes which bring

about an N distribution in the lower troposphere that favor the superrefraction. DeLailed considerations of both explanations, graphs of the computed refraction index

and radarscope pictures are presented. (Met. Abs. 11. 2-171) --I.L. D.

E-568 Millington, G. , Propagation at great heights in the atmosphere. Marconi Review,

London, 21(131): 143-160, 1958. 9 figs. , 10 refs. , 62 eqs. DLC--This article considers tropospheric propagation over the earth through an atmosphere which is

standard at small heights but in which the refractive index approaches unity asymptotically at great heights. The departure from the linear decrease leads in the geometric optical region to a reduced horizon distance and in the diffraction region to

a reduction in height gain. The latter may be interpreted as an equivalent change

in distance which is found to be effectively independent of frequency and identical

with the decrease in horizon distance. It follows that the shape of the propagation curve as a function of distance is maintained and that the important thing to establish is the position of the horizon for the assumed model of the atmosphere. The

theory is illustrated by using a refraction index that decreases exponentially to unity. (Met. Abs. 12. 5-66) -Author's abstract.

E-569 Misme, P. , The correlation between the electric field at a great distance and a new radio meteorological parameter. IRE Transactions on Antennas and Propagation, N. Y. , 6(3):289-292, July 1958. 9 figs. , foot-refs. DLC -The daily variations of hourly median 1046 Mc transmission loss recorded over a 370 km propagation path, are found to be correlated with a new meteorological parameter that combines the thermodynamic stability of the atmosphere and the useful gradient of the

radio refractive index. The thermodynamic stability is evaluated from the area contained between the observed temperature distribution with height and the pseudo

adiabatic temperature lapse, while the useful gradient of the refractive index is derived from ray tracing considerations, and is weighted toward the initial gradient.

--Author's abstract.

E-570 Moler, William F. (U.S. Navy Elec. Lab. ), Macro- and meso-scale meteorological

effects upon microwave trans-horizon fields . Weather Radar Conference, 7th,

Miami Beach, Florida, Nov. 17-20, Proceedings, issued 1958. Sec.E:26-33.

7 figs. , 7 refs. DWB (M01. 81 R124pc, 1958) --Results of correlations between X

and L band microwave signal strengths and meteorological parameters are presented. Median signal strengths over periods of the order of days are best correlated

with the macro-scale middle and upper tropospheric flow. Short term large scale

fluctuations of trans-horizon electromagnetic fields are often observed during
141

apparently spatially homogeneous time stationary macro-scale synoptic regimes.

A meso-scale analysis shows that these fluctuations occur concurrently with minor

perturbations developing over or moving across the radio links. (Met. Abs.

12.2-93)--Author's abstract.

E-571 Okamoto, Hironobu; Aida, Kazuo and Ose, Masami, Scattering short-waves over

the sea. Japan. Radio Research Laboratories, Tokyo, Review, 4(14): 16-19, Jan. 1958. 4 figs. , table, 2 refs. In Japanese; English summary p. 16. DLC--New

type of scattering echoes of radio waves were observed in almost the entire course

of Japan's Antarctic Research Expedition I. These echoes have regular diurnal

variations and are distinctly different in strength depending whether they are over

the sea or near the land. This paper describes the type of the echoes and their

diurnal variations, including some investigations carried out after returning to Japan. (Met. Abs. 14. 5-139) -Authors' abstract.

E-572 Onoue, Michio; Hirai, Masaichi and Niwa, Shuntaro, Results of experiment of

long distance overland propagation of ultra-short waves. Japan. Radio Research

Laboratories, Journal, 5(20):79-94, April 1958. 11 figs. , 6 tables, 18 refs.

Also Japanese version with English Summary in its Review, 4(15):85-94, April

1958. DBS--This paper explains the results of a VHF and UHF path loss test per- formed over a distance of 364 km between Tokyo and Osaka. Frequencies used

were 159.49 Mc and 600.00 Mc. The measurement was made from Nov. 1956 to Aug. 1957. The data were statistically analyzed to investigate the temporal var- iation of field strength, the spatial correlation of field strength, and relations

between the transmission loss and meteorological conditions. (Met. Abs.

14. 4-119)

E-573 Parry, C.A. , Factors affecting the use of over-the-horizon links in telecommunication networks. Communication and Electronics, N. Y. , No. 38:485-496, Sept. 1958.

9 figs. , 2 tables, 20 refs. DLC--An attempt is made to evaluate the scatter link,

not so much in terms of performance, as in its compatibility with existing communication facilities and surrounding facets of the social technology and economic

structure. It is pointed out that the scatter link has the basic advantage of being

effective over relatively large spans without losing the principal advantages that

have been normally associated with radio relays. --E. K.

E-574 Prosin, A. V. , K raschetu moshchnosti rasseianiia pri dal'nem troposfernom

rasprostranenii ul'trakorotkikh voln. (Calculations of scattered power in long

distance tropospheric propagation of ultrashort waves.) Elektrosviaz', Moscow,

12(8):13-21, Aug. 1958. 17 refs. , 24 eqs. DLC. Transl. into English in Telecommunications, N. Y. , No. 8:811-822, 1958. --The author develops a method for calculating scattered power in connection with the use of directional and nondirectional antennas. Some conclusions are reached concerning antenna directivity in the horizontal and vertical planes. Losses in antenna gain are also

studied. Experimental results are compared with theoretical data. (See ref. E-765)»R.M.

E-575 Prosin, A.V.and Tsvetkov, A. N. , Radioreleinye linii sviazi. (Radio relay

links.) Moscow, Akademiia Nauk SSSR, 1958. 108 p. 33 figs. , 18 eqs. DLC

(TK6553.P74)--A popular science booklet containing a discussion of the principles and equipment of radio relay links operating within the normal horizon

and beyond the horizon, in the latter case by means of tropospheric and iono-
142

spheric propagation of ultrashort waves. These links are intended to facilitate

multichannel telephone and telegraph service and the interurban transmission of

television programs. Existing Soviet radio relay links and some in the planning

stage are mentioned. Some applications of radio relay communications are also

discussed. --R. M.

E-576 Rautenfeld, Friedrich von, Zur statistischen Auswertung von Feldstarkemessunaen

(Vorlaufige Mitteilung) . (Statistical evaluation of field strength measurements.

(Preliminary communication). ) Rundfunktechnische Mitteilungen, Hamburg, 2(4):

178-180, Aug. 1958. 3 figs. , 12 refs. English, German and French summaries

p. 178. DLC--The author describes the fundamental outline of a method for storing

several statistically fluctuating parameters on a magnetic tape, which also operates with cheap domestic magnetic sound recording currently to be found on the

market. The advantages compared with the well known method of recording curves on paper tape: facility of storage of measured values and protocol texts, automatic

maintenance of time correlation, relief of a fully automatic statistical evaluation,

the possibility of using tape again after evaluation. Furthermore, a new evaluation device is mentioned which simultaneously finds and prints as percentages the

results of statistical distributions, statistical sums and correlation of several

variables. --Author's abstract.

E-577 Richards, E. G. , The estimation of transmission loss in the trans-horizon region.

Institution of Electrical Engineers, London, Proceedings, Pt. B, 105 (Supplement 8):

177-183, 1958. 9 figs. , 2 tables, 11 refs. , 16 eqs. DN-RL--The expression for the scattering cross section derived by Batchelor has been integrated over the useful scattering volume for transmitting and receiving aerials aligned on a great circle

path, and formulas have been derived for the transmission loss. The application of

the theory to experimental results at 86,3000 and 10,000 Mc/s suggests that meansquare variations of refractive index of the atmosphere may be independent of height

up to about 2200 ft and may then vary with the inverse square of height. --Author's

abstract.

E-578 Rider, G.C., Propagation measurements at 858 Mc/s over paths up to 585 km.

Marconi Review, London, 21(131): 184-197, 1958. 13 figs. , 9 refs. DLC--The

purpose of this paper is to present the results of some propagation measurements

at a frequency of 858 Mc/s made in the United Kingdom over a two and one-half

years period. The objective was to obtain the knowhow in the application of the

tropospheric scatter mode of propagation. The path investigated have been progressively increased in length up to a total distance of 585 km. The general picture presented by the measurements described accords well with comparable published results. However, the attenuation rate of 0. 103 db/km may be noted, as

also the diversity distances which are larger than was expected. --E. K.

E-579 Rider, G.C., Some tropospheric scatter propagation measurements and tests of

aerial siting conditions at 858 Mc/s. Institution of Electrical Engineers, London,

Proceedings, Pt.B, 105 (Supplement 8): 143-152, 1958. 10 figs. , 6 tables, 8 refs.

DN-RL--A tropospheric scatter link has been in operation for three months over a 98 mi path and for eight months over a 200 mi path at a frequency of 858 Mc/s.

Received signals are shown to agree well with predictions of mean levels, while

seasonal and diurnal variations are slightly less than was anticipated. Height/

gain and space diversity tests are described, and a comparison is made of signals

received at four sites of very different aspects within the same locality. The fast

fading is described in terms of fading range and fading rate, and an attempt is
143

made to relate this information, together with the slower changes, to meteorological observations. A program of synchronous beam rotation has been carried out,

and tests of received polarization show the polarization to be well preserved in

propagation. The disturbing effect of local flying is investigated and discussed.

--Author's abstract.

E-580 Riggs, Lowell P. , An investigation of the atmospheric physical conditions associated with microwave propagation. Texas. Agricultural and Mechanical College,

Contract AF 19(604)-1564, Technical Note, No. 4, March 1958. 65 p. 30 figs,

(incl. photos), 5 tables, 20 refs. , eqs. DWB (M94. 7 T353te)--In an attempt to evolve procedures whereby meteorologists, using ordinary weather observations, can predict anomalous propagation of radar energy, relationships between radar

observations and weather factors which might reasonably be expected to influence

"trapping" have been examined. No significant correlation between any single

meteorological parameter and the degree of trapping could be found. Instead, as might be expected, it appears that a number of factors contribute to the degree of

refraction. The most sensitive parameter is (for the regions studied) the degree

of stratification of layers from the surface to 5000 ft alt. When the height of the

low level moisture layer reaches this altitude, trapping is negligible. Procedures

for the preparation of objective forecasts of anomalous propagation are presented.

(Met. Abs. 10. 5-214) -Author's abstract.

E-581 Ringwalt, D.L.; Ament, W.S.and MacDonald, F.C., Measurements of 1250 Mc

scatter propagation as function of meteorology. IRE Transactions on Antennas and

Propagation, N. Y. , 6(2):208-209, April 1958. DLC--The evaluation of 105 full length refractometer soundings showed a break of about 40 or 50 n units in a 1000

ft interval centered at altitudes from 4000 to 6000 ft, moist oceanic air of high re- fractive index being found below the break. Near and above the inversion, the

Rayleigh fading was usually superimposed on a slower fade having a period of

about one minute with fades of about 10 db. The slow underlying fade in the signals at inversion height suggests the duct mechanism, while the midpath shear

correlation supports the leaky ceiling picture. --E. K.

E-582 Rowden, R.A. ; Tagholm, L.F. ; Stark, J. W. , A survey of tropospheric wave

propagation measurements by the B. B.C. . 1946-1957. Institution of Electrical

Engineers, London, Proceedings, Pt. B, 105 (Supplement 8) :84-90, 1958. 4 figs. , table, 7 refs. DN-RL--The paper describes beyond-the-horizon tropospheric wave

propagation measurements made by the B. B.C. Research Department during the

years 1946-57. Initially, the data were used to assist the B. B.C. in planning

common frequency working within the United Kingdom for VHF sound broadcasting

and television, and later became a contribution toward the collection of data organized internationally by the C.C.I. R. and used by that body in the preparation of

field strength/distance curves representing average tropospheric conditions.

--Authors' abstract.

E-583 Schmelovsky, Karl-Heinz, Probleme der Ausbreitung in tropospharischen und

ionospharischen Wellenleitem. (Problems of propagation in tropospheric and ionospheric wave guides. ) Germany. (Democratic Republic) Meteorologischer und

Hydrologischer Dienst, Abhandlungen, 7(49), 1958. 41 p. 14 figs. , 2 tables,

23 refs. , numerous eqs. DLC--An attempt is made to find a general procedure for determining the propagation characteristic of a wave guide, in particular its propagation damping. In the derivation of these characteristics the author constructs a model which describes the field in the wave guide as a process of interference of
144

waves which are reflected at the limits. By using this model it is possible to re- tain the concept of the reflection factors. The problems considered include ex- clusively wave guides having a propagation constant that is very complex as a re- sult of radiation or reflection losses, thereby the boundary wavelength looses its

fundamental importance; approximately spherical symmetrical guides are present;

the ratio of longitudinal to transverse measurements is usually substantially

smaller than in the case of artificial hollow guides. The mathematical treatment

of the propagation in the case of homogeneous wave guides, in tropospheric wave

guides and in homogeneous wave guides are presented and application and illustrations for the interpretation of sunrise effects on the atmospheric noise level,

in the longest wavelengths and propagation constants of tropospheric wave guides

are given. (Met. Abs. 11 E-137)--I. L. D.

E-584 Schunemann, R. , Uber die Ausbreitung ultrakurzer Wellen an rauhen Schichten. (Propagation of ultrashort waves over rough surfaces. ) Hochfrequenztechnik und

Elektroakustik, Leipzig, 66(6): 171-173, May 1958. 2 refs. , eqs. DLC --Supplementing an earlier paper on long distance propagation mechanisms (see E-492)

received field intensities are calculated for scattering layer sections with different degrees of overlapping in the 1st Fresnel zone. The calculated values are found to be within the measurement error even with small degrees of overlapping

and small variations of refractive index gradient. Time variations may be determined from the probability distribution of amplitudes of a constant vector and a Rayleigh distribution vector. --Transl. of author's abstract.

E-585 Senn, H.V. (Marine Lab. , Univ. of Miami), Observations and possible explanations of certain fine lines. Weather Radar Conference, 7th, Miami Beach, Fla. , Nov. 17-20, 1958, Proceedings, issued 1958. Sec. D:31-36. 4 figs. , table,

6 refs. DWB (M01. 81 R124pc, 1958) -Observations of several radar "thin bands"

on both MPS-4, 4. 7 cm and SP-1M, 10. 7 cm radars show that at least one type of

band is confined to very low levels. Several possible explanations are given for the existence of these bands. But most evidence seems to indicate that ground

targets are being observed, probably as a result of a combination of refraction and

forward scattering from abrupt low level changes in the refractive index which are caused by local convective activity. Another type of fine line, which appears as

a circular arc on airborne radars, can be attributed to solid targets which are picked up on side lobes of the radar beam. (Met. Abs. 11 H-132) --Author's abstract.

E-586 Smyth, John B. , Tropospheric radio propagation. Report on URSI Commission II. Institute of Radio Engineers, N. Y. , Proceedings, 46(7): 1358-1361, July 1958.

DLC --The technical papers and discussions presented were organized into three

broad categories: 1) tropospheric propagation within the horizon, 2) tropospheric

propagation beyond the horizon, and 3) radio and meteorology. Each individual

contribution is briefly summarized. --E. K.

E-587 Sofaer, E. , Phase coherent back scatter of radio waves at the surface of the sea.

Institution of Electrical Engineers, N. Y. , Proceedings, 105B(22):383-394, July

1958. 15 figs. , 3 tables, 6 refs. , appendices. DLC--Soon after the completion

of the B. B.C. *s television transmitting station in Devon and the establishment of a full scale service, complaints were received from coastal areas around Plymouth

that the transmission was subject to rhythmic variations in amplitude. The investigations which followed these reports are described. The variations are found to be

due to phase coherent back scatter from the sea, and to depend on the configuration of the surface of the sea. The phenomenon is examined theoretically.

--Author's abstract.
145

E-588 Starkey, B. J. ; Turner, W. R. and Badcoe, S.R., The effects of atmospheric discontinuity layers up to and including the tropopause on beyond-the-horizon propagation phenomena. Institution of Electrical Engineers, London, Proceedings,

Pt. B, 105 (Supplement 8):97-105, 1958. 11 figs. , table, 11 refs. , 7 eqs. DN-RL--

Field strength measurements at distances extending far beyond the horizon from a transmitter on a frequency of 91. 3 Mc/s have been carried out in an aircraft flying

at heights of about 10,000 ft. It is shown that the results obtained and other ex- perimental data can be explained more readily on the assumption that the mechanism of tropospheric propagation over such distances is due to reflections from discrete discontinuity layers in the atmosphere up to the height of the tropopause

than by the theory of forward scatter due to turbulence. --Authors' abstract.

E-589 Tao, Kazuhiko; Orimo, Jinsuke; Sakurazawa, Akira et al. , The present status

of the scatter propagation. Pt. 1. Japan. Radio Research Lab. , Tokyo, Quarterly

Review, 3(13):256-283, Oct. 1957. English summary p. 256. 17 figs. , tables, numerous eqs. , 67 refs. Pt. 2. Ibid. , 4(14):20-60, Jan. 1958. Numerous figs. , tables (some fold.), 70 refs. , eqs. In Japanese. DLC--In recent years a series

of experiments on both ionospheric propagation of VHF waves and tropospheric

propagation of ultrashort waves and microwaves far beyond the horizon have been

carried out in various countries. The propagation mode of these experiments has

been attributed to the scattering by fluctuation of electron density or refractive

index. Therefore, the subject of radio propagation by scattering processes has

acquired a great theoretical and practical importance. The object of this paper

is to introduce the present status of the scatter propagation both in the ionosphere

and troposphere. In Ch. 1 of the paper, turbulence in the ionosphere and troposphere and the various theories of scattering in terms of turbulence are discussed.

In Ch. 2, summaries of the experiments carried out in various countries and the

instruments used, the propagation characteristics of ionospheric scattering, and

moreover, the utilization in practical communication are described. In Ch. 3,

the same problems stated in Ch. 2 are introduced for tropospheric scattering.

(Met. Abs. 14. 1-58) -Authors' abstract.

E-590 Tatarskii, V.I. , O rasprostranenii voln v lokal'no izotropnol turbulentnot srede

s plavno meniaiushchimisia kharakteristikami . (Propagation of waves in a locally

isotropic turbulent medium with gradually changing characteristics. ) Akademiia

NaukSSSR, Doklady, 120(2):289-292, 1958. 9 refs. , 127 eqs. DLC -It is shown

that in calculating phase and amplitude fluctuations of short waves propagated in a real atmosphere, account must be taken of the fact that turbulence along the

path of the beam may vary in intensity, as, for example, with altitude. Expressions are derived for amplitude and phase fluctuation intensity and variations in

the refraction index are considered according to the two-thirds law. --R. M.

E-591 Trenev, N. G. , Difraktsiia poverkhnostnykh elektromaqnitnykh voln na impedansno¥ stupenke . (The diffraction of surface electromagnetic waves on the impedance

stage.) Radiotekhnika i Elektronika, Moscow, 3(l):27-37, Jan. 1958. 5 figs. , 5 refs. , 52 eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 3(l):38-53, 1958. DLC --This article considers the problem of diffraction of sur- face E and H waves on the impedance stage. Expressions are given for the reflection and transmission coefficients. The diffraction field and the radiation characteristics are determined. --Author's abstract.
146

E-592 Trenev, N. G. , Difraktsiia poverkhnostnykh elektromaqnitnykh voln na polubesko- nechnoi impedansnoY ploskosti. (Diffraction of surface electromagnetic waves on

a semi-infinite impedance plane.) Radiotekhnika i Elektronika, Moscow, 3(2):

163-171, Feb. 1958. 4 figs. , 3 refs. , 50 eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 3(2) -.227-238, 1958. DLC --The article considers

the problem of diffraction of surface E and H waves at the edge of a two sided

impedance plane. Expressions are derived for the coefficients of reflection and

transmission, the diffracted field and the radiation diagrams. --Author's abstract.

E-593 Trolese, L. G. and Anderson, L.J. , Foreground terrain effects on overland UHF

transmission. IRE Transactions on Antennas and Propagation, N. Y. , 6(4):330-

337, Oct. 1958. 22 figs. , table, foot-refs. DLC--This paper describes an ex- perimental study of the influence of the shape of foreground terrain profiles near

terminals of UHF links on the received field. A gently rounded shape of the foreground profile causes a marked diffraction pattern to be superimposed on the nor- mal variation of field strength with height. The diffraction geometry shows similarity to knife edge geometry and the rounded terrain feature appears to act geometrically as an equivalent knife edge. The amplitude of the spatial variations

in signal are, however, much greater than knife edge theory predicts. A sizeable

foreground diffraction enhancement of received field can be realized by locating

the antenna at the height of the first diffraction maximum. Changing refraction

due to meteorological variations can change both the position in height and intensity of the diffraction pattern. --Authors' abstract.

E-594 Tsel'min, A. E. and Krauz, L.I. , Vliianie vysot antenn na moshchnost' priema pri

rasprostranenii v usloviiakh troposfernogo rasseianiia. (The effect of aerial height on received power for propagation in conditions of tropospheric scattering.) Radiotekhnika, Moscow, 13(11): 11-17, Nov. 1958. 5 figs. , 4 refs. , 29 eqs. Transl.

into English in Radio Engineering, N. Y. , 13(11):12-21, 1958. DLC --An expression

for the attenuation function is derived which makes it possible to design a communication link using tropospheric scattering of radio waves in the meter band,

taking into account the effect of the Earth's surface on the radiation pattern of the

aerial. Graphs are given showing the dependence of the attenuation function on

distance and antenna heights for the case where the dependence of turbulence on

height has a quadratic form. --Authors' abstract.

E-595 U. S. Navy Weather Research Facility, Some aids for estimating atmospheric refrac - tive conditions . Project AROWA, Interim Research Report on Task 31 (Meteorological aspects of refraction and propagation of radar waves), June 1958. 52 p. 13

figs. , 5 charts, 2 tables. Bibliog. p. 39-52. DWB (M93. 1 U585so)--The U.S. Navy

Weather Research Facility has been developing new techniques for predicting the

atmospheric refractive index as a part of the meteorological aspects of refraction

and propagation of radar waves. This report contains the results of their efforts.

The report covers the refractive index formulas, the atmospheric effects on radar

propagation, the needed computation aids, the atmospheric refractive data and 113

selected references on related atmospheric conditions. (Met. Abs. 11.3-224)

»N. N.

E-596 Vysokovskii, David M. , Diffuznoe rasprostranenie ul'trakorotkikh voln v troposfere pri antennakh s bol'shoi napravlennost'iu. (Scatter propagation of ultrashort

waves in the troposphere with highly directive antennas.) Elektrosviaz', Moscow,

12(5):16-22, May 1958. 4 figs. , 5 refs. DLC. Transl. into English in Telecommunications, N. Y. , No. 5:488-497, 1958. --Expressions are derived for the power
147

scattered by inhomogeneous turbulence, losses in antenna gain, and the widening

of the radiation pattern with scatter propagation for wide and narrow radiation pat- terns. It is found that the scatter volume integrated as a prism is twice as large as the actual scatter volume, requiring the division of the results by 2 for narrow

radiation patterns. It is shown that with a radiation pattern width of 0. 25-3°

(antenna gain 58-36 db), antenna gain losses obtained by Booker and Bettencourt

are 4-8 db too high. --R. M.

Vysokovskii, David Markovich, Nekotorye voprosy dal'neqo troposfernogo rasprostraneniia ul'trakorotkikh radiovoln. (Long distance tropospheric propagation of

ultrashort radio waves.) Moscow, Izdatel'stvo Akademiia Nauk SSSR, 1958. 153

p. 58 figs. , 173 refs. , numerous eqs. At head of T-p: Akademii Nauk SSSR.

Institut Nauchno-TekhnicheskoV Informatsii. --This is a review of international lit- erature including a large amount of data and mathematical formulation. The material is discussed under the following seven chapter headings: 1) Atmospheric tur- bulence and refractive index fluctuations; 2) Theory of radio wave scattering by

tropospheric turbulent inhomogeneities; 3) Fluctuations of the scattered field;

4) Experimental investigation of field characteristics in long distance propagation;

5) Phase fluctuations in scatter propagation; 6) Calculation of USW long distance

links, and 7) Equipment for USW long distance links. --G.T.

Wait, James R. , On the theory of propagation of electromagnetic waves along a curved surface . Canadian Journal of Physics, Ottawa, 36(1):9-17, Jan. 1958.

2 figs. , 16 refs. DLC--The problem of propagation of vertically polarized waves

along a surface whose curvature and electrical properties have a discontinuity is

considered. The mutual impedance Z between two short vertical antennas on

either side of the boundary of separation is considered to be the fundamental

quantity which is sought. By utilizing the principle of stationary phase and con- cept of surface impedance, an approximate expression is derived for Z. It is

shown that to a first order of magnitude, the effects of the conductivity contrast

and curvature change are additive corrections to the mutual impedance between

dipoles over a single homogeneous spherical surface. --Author's abstract.

Waterman, A.T. , Jr. , A rapid beam swinging experiment in trans-horizon propagation. IRE Transactions on Antennas and Propagation, N. Y. , 6(4):338-340, Oct.

1958. 7 figs. , 8 refs. DLC--By using a broadside phased array for an antenna, a narrow beam can be swung rapidly and in quick succession through a limited sector

by fast control of the phasing, rather than by movement of the entire antenna structure. This technique is used at the receiving end of a 101 mi beyond the horizon

transmission path in order to probe the portion of the troposphere through which the

signal is propagated. At a frequency employed of 3. 12 kmc, a 0. 49 ° beam is

swung in azimuth through a 4. 2° sector each tenth of a second. A variety of phenomena are observed with this technique which have not been directly apparent in

slower beam swinging experiments. The beam broadening effect attributed to at- mospheric scattering is not always evident on any one sector scan. However, the

change from scan to scan is frequently rapid enough so that a time average would

show the broadening. At times the scan to scan changes are systematic and show

a continuity indicative of a motion of the scattering or reflecting regions; in some

cases this motion is too rapid to be accounted for by transport of air, thus implying a wave motion rippling through the atmosphere. At other times the atmospheric

structure is too fine to be resolved by the beamwidth employed, and the time variations too rapid to reveal a continuity from one scan to the next. —Author's abstract.
148

E-600 Waterman, A.T. , Jr. , Some generalized scattering relationships in trans-horizon

propagation. Institute of Radio Engineers, N. Y. , Proceedings, 46(11): 1842-1848,

Nov. 1958. 4 figs. , 2 tables, foot-refs. , 18 eqs. DLC--An analysis is made of

the consequences to be derived from some fairly broad assumptions as to the nature

of turbulent scattering and its effect on waves propagated through the troposphere.

The intent is to provide a means for testing the general applicability of this model

as an explanation for trans-horizon propagation. General relationships for the var- iation of received power with distance are derived for various scatter angle dependencies, and for various beam width configurations. These relationships are then

extended to cover the phenomenon of aperture medium coupling loss. The results

are applied toward distinguishing those experiments which are definitive from those

which are not. --Author's abstract.

E-601 Yeh, L.P. , Basic analysis on the controlled carrier operation of tropospheric scat - ter communications system. IRE National Convention Record, 8:261-283, 1958.

13 figs. , 24 refs. , 14 eqs. DLC--This paper analyzes the possibility of applying

controlled carrier operation to tropospheric scatter communication systems which

means that the transmitter power will change as closely as possible in accordance

with the fluctuation of the received signal level with time. Basic requirements,

mainly in the field of propagation, are discussed in detail. Certain advanced

thinking in tropospheric scatter propagation is also presented, such as: 1) one

minute as the sampling period of Rayleigh Distribution Fast Fading; 2) long term

minutely median distribution as the long term slow fading distribution; 3) probability combination of fast and slow fading distributions as the combining fading distribution to determine system reliability; 4) effect of detector time consonant on

the fast fading distribution. --Author's abstract.

E-602 Yeh, L.P. , Tropospheric scatter system design. Communication and Electronics,

N.Y. , No. 39:707-716, Nov. 1958. 8 figs. , 5 tables, 14 refs. DLC-A comprehensive procedure is presented, from an approach partly experimental and partly

theoretical, for the design of tropospheric scatter communication systems, using

single side band (SSB) or frequency modulation (FM) and frequency division multiplex (FDM). -E. K.

1959

E-603 Ames, L.A. and Rogers, T.F. , 220 Mc radiowave reception at 700-1000 miles.

Institute of Radio Engineers, N. Y. , Proceedings, 47(1):86, Jan. 1959. Fig.,

6 refs. DLC--An account of two airborne investigations of long distance 220 Mc

field strength conducted in March and April 1958. Results of measurements during the two flights are presented. In the latter case, the signal was still being

received at 1000 statute miles, where it was a very few db above the noise level.

The indicated median path loss throughout the 800-1000 mi region was 275 db +

5 db. -E. K.

E-604 Anderson, W. L. ; Beyers, N. J. and Fannin, B. M. , Comparison of computed with

observed atmospheric refraction. IRE Transactions on Antennas and Propagation,

N.Y. , 7(3):258-260, July 1959. 2 figs. , 2 tables, 3 refs. , 6 eqs. DLC--Ray

tracing methods have been applied in the computation of atmospheric refraction

for a path at White Sands Missile Range, N. Mex. , with a range of about 48 mi

and an elevation angle of 14. 5 milliradians. The atmosphere was assumed to be

horizontally stratified. Refractive index profiles were derived from meteorological data obtained from surface observations, wiresondes, radiosondes, and
149

airborne refractometer soundings. The profiles were classified "A", "B", or "C",

in descending order of reliability, prior to radar refraction computations. The classification system considered the variety of data available, the time lag between

radar and weather observations, and the proximity of the sounding to the propagation path. A good correlation between observed and computed angles resulted and

the correlation was directly related to the classification. Radar observations were made in the X band and instrumental precision maintained to within 0. 25 milliradian.

Total bending ranged between 0. 56 and 2. 23 milliradians, with standard deviation

0.38 milliradian. The rms deviation of computed from observed angles ranges from

0. 19 to 0.41 milliradian for class A and class C data, respectively. The correlation coefficient ranges from 0.81 to 0. 13. It is concluded that within the limits of

this experiment: a) ray tracing methods are justified, b) horizontal stratification

may be assumed, and c) the accuracy of bending predictions is increased by improving the meteorological data. --Authors' abstract.

E-605 Atlas, Dayid, Radar studies of meteorological 'angel' echoes . Journal of Atmospheric and Terrestrial Physics, N. Y. , 15(3/4): 262-287, Oct. 1959. 19 figs. , bibliog. p. 283-284, 9 eqs. DLC--A review, supplemented by new data, is pre- sented of 'angel' echoes from meteorological sources. The major angel types are enumerated. Special angel types, such as those associated with the sea breeze

front add to the impressive evidence of the association of angels with meteorologically induced gradients in refractive index. In every case, however, the gradients

required by theory exceed reasonable or measured values by at least one or two

orders of magnitude, apparently due in large part to the lack of high resolution re- fractometer measurements. The observations indicate frequent conditions suitable

for enhanced forward scatter beyond the horizon and also testify to the feasibility

of Friend's 1939 proposal to use radio reflections for sounding air mass boundaries.

--Author's abstract.

E-606 Atlas, D. (GRD, A. F.Cambridge Res. Ctr. ), Sub-horizon radar echoes by scatter

propagation. Journal of Geophysical Research, Wash. ,D.C. , 64(9): 1205-1218,

Sept. 1959. 8 figs. , 3 tables, 13 refs. , 8 eqs. DLC-The paper deals with a unique 3 cm radar observation in which echoes arranged in cellular and striated

patterns were detected out to a maximum range of 90 mi. The cellular structure

closely resembles a Benard convection pattern and the cell scale is consistent

with that to be expected when convection is restricted to a layer of the observed

depth. The echoes cannot be attributed to clouds or precipitation, which were

absent. Birds, insects, or other particulate matter are also illogical targets.

Direct backscatter or angel echoes from atmospheric inhomogeneities are also

precluded except at very short ranges, because of the restricted echo heights

and great ranges. The echoes can only be attributed to a mechanism of forward

scatter by atmospheric eddies to ground targets and back, via the same path. The

resulting echo structure is then that of the convectively patterned atmospheric

"mirror" upon which are superimposed the more prominent features of the topography. Theoretical analysis indicates that the magnitude of the forward scatter

intensity function must be extremely high. However, extrapolation of the frequencies with which smaller scatter intensities have been observed indicates that the

required magnitude might be expected to occur with a frequency which is in general accord with the rarity of the present phenomenon. Although the required in- dex irregularities are extremely sharp, they are physically conceivable. (Met.

Abs. 11 H-3) -Author's abstract.
150

E-607 Baeyer, H. J. , Selective fading effects on UHF tropospheric scatter path. Institute

of Radio Engineers, N. Y. , Proceedings, 47(ll):2021-2022, Nov. 1959. 8 figs. , ref. DLC--Some results of tests that were made during the winter 1954-55 are shown

on figures. The majority of fading effects had the characteristics of a level depression moving in either direction through the frequency band, only a few had more ran- dom character. The greatest observed level differences over the frequency band

were of the order of 15-20 db per Mc lasting for not more than one second. --E. K.

E-608 Bass, F. G. and Kaner, E.A. , Korreliatsiia fliuktuatsii elektromagnitnoqo polia

v srede so sluchainymi neodnorodnostiami nad ideal 'no provodiashchel ploskost'iu . (Correlation of fluctuations of an electromagnetic field in a medium with random inhomogeneities over an ideally conducting surface.) U. S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 2(4):

565-572, 1959. 3 refs. , 12 eqs. DLC --Space correlation functions are determined.

Calculations are based largely on a companion paper by Kaner and Bass in the same

issue of the journal. (See E-645). --R. M.

E-609 Bean, Bradford R. , Climatology of ground based radio ducts. U. S. National Bureau

of Standards, Journal of Research, Sec. D, 63(l):29-34, July-Aug. 1959. 7 figs. , 3 tables, 8 refs. , 17 eqs. DLC, DBS --An atmospheric duct is defined as occurring

when geometrical optics indicate that a radio ray leaving the transmitter and passing upward through the atmosphere is sufficiently refracted that it is traveling parallel to the Earth's surface. Maximum observed incidence of ducts was determined

as 13% in the tropics, 10% in the arctic and 5% in the temperate zone by analysis of

3 to 5 yrs of radiosonde data for a tropical, temperate, and arctic location. Annual

maximums are observed in the winter for the arctic and summer for the tropics. The

arctic ducts arise from ground based temperature inversions with the ground temperature less than -25°C while the tropical ducts are observed to occur with slight

temperature and humidity lapse when the surface temperature is 30°C and greater.

--Author's abstract.

E-610 Bean, B. R. and Gallet, R.M. (both, Nat'l. Bur. of Stands. .Boulder, Colo.),

Applications of the molecular refractivity in radio meteorology. Journal of Geophysical Research, Wash. ,D.C, 64(10): 1439-1444, Oct. 1959. 5 figs. , 13 refs.,

9 eqs. DLC --Consideration of the molecular refractivity has led to a value of the

radio refractive index referred to zero altitude or sea level that effectively removes

the systematic altitude dependence of air density. The advantages of this new

parameter are illustrated by two applications. The first application, the preparation of climatic charts of the radio refractive index, illustrates that this new parameter brings climatic differences into sharp relief. The second application deals

with the vertical variation of air mass properties across a classic warm front and

clearly delineates air mass differences, thus indicating the utility of this new

parameter for synoptic studies. (Met. Abs. 14. 7-105) --Authors' abstract.

E-611 Bean, B. R. and Horn, J. D. , Radio refractive index climate near the ground. U.S.

National Bureau of Standards, Journal of Research, Sec. D, Radio Propagation,

63(3): 259-271, Nov. /Dec. 1959. 14 figs. , 5 tables, 17 refs. , 5 eqs. DLC»The

radio refractive index of air is a function of atmospheric pressure, temperature

and humidity and is found to vary in a systematic fashion with climate. It was

found that the surface value of the refractive index may be estimated four to five

times more accurately from charts of reduced to sea level values than from similar

sized charts of surface index. Worldwide maps of 5 yr means of this reduced value

are presented for the months of Feb. and Aug. , for the minimum monthly mean value

of the year and for the range of monthly mean values. Year to year variation of
151

monthly means is also considered. Application of these data to the prediction of

radio field strength indicate a possible 30 db difference in median level of identically equipped tropospheric communications system due to climate alone. --Authors'

abstract.

E-612 Bean, B. R. and Riggs, L.P. , Synoptic variation of the radio refractive index. U.S. National Bureau of Standards, Journal of Research, Sec. D, 63(l):91-97,

July/Aug. 1959. 18 figs. , 12 refs. , 4 eqs. DLC, DWB--The synoptic variation

of the atmospheric radio refractive index, evaluated from standard weather observations, is examined during an outbreak of polar continental air. It is found that

the reduced-to-sea-level value of the refractive index is a more sensitive synoptic parameter than the station value. The reduced value is quite sensitive to the

humidity and density structure of the storm under study while the great station

elevation dependence of the station value tends to mask synoptic changes. The

reduced value changes systematically with the approach and passage of the polar

front. The present system shows a consistent increase of the reduced value in

the warm sector of the wave and a marked decrease behind the cold front. (Met.

Abs. 11. 4-241) -Authors' abstract.

E-613 Bean, B. R. ; Riggs, L.P. and Horn, J. D. , Synoptic study of the vertical distribution of the radio refractive index. U.S. National Bureau of Standards, Journal of

Research, Sec. D, 33(2): 249-254, Sept. /Oct. 1959. 14 figs. , 16 refs. , 3 eqs.

DWB, DLC--An analysis of the vertical structure of an intense outbreak of continental polar air is presented in terms of the radio refractive index of the atmosphere.

Employed for the first time is a reduced index analogous to potential temperature.

The reduced value shows the refractive index structure more clearly than the classical methods used heretofore. The new unit is a measure of both atmospheric density and humidity and shows, on a single cross section, the air mass structure and

the dynamic mixing of air around the frontal interface. (Met. Abs. 14. 7-109)

--Authors' abstract.

E-614 Bean, B. R. and Thayer, G. D. , Central radio propagation laboratory exponential

reference atmosphere. U.S. National Bureau of Standards, Journal of Research,

Sec. D, 63(3):315-317, Nov. /Dec. 1959. Fig., table, 6 refs. , eq. DLC--The

background and development of an exponential model of stratospheric radio refractivity, the "C. R. P. L. Exponential Reference Atmosphere" is outlined. A set of

ray tracings for the model is presented in the form of tables of refraction variables

for the complete range of observed values of surface refractive index. A detailed

analysis of the accuracy of the ray tracing and tabulation methods is made for these tables. The variables are presented as numbers between one and ten multiplied by the appropriate power of 10, thus maintaining a maximum number of significant figures. The tables may be used for the solution of practical refraction

problems involving elevation angle errors, range errors, and similar quantities.

--Authors' abstract.

E-S15 Bean, B. R. and Thayer, G. D. (both, Nat '1. Bu. of Stands. .Boulder, Colo.),

Models of the atmospheric radio refractive index. Institute of Radio Engineers,

N. Y. , Proceedings, 45(5, Pt. 1): 740-755, May 1959. 24 figs. , 3 tables, 24 refs.,

29 eqs. DWB--Evaluation of atmospheric refraction effects on UHF-VHF radio propagation has long been accomplished with the convenient four-thirds earth concept

of SCHELLING, BURROWS and FERRELL. This method has proven particularly useful in evaluating performance of point-to-point radio communications systems. However, relatively new long range applications have demanded a model of atmospheric
152

radio refractive index more representative of observed refractive index profiles

than the simple linear decay inherent in the four-thirds earth approach. This paper

introduces two models of atmospheric radio refractive index which can be used to predict refraction effects from the value of the refractive index at the transmitting

point. Both models offer considerable improvement over the four-thirds earth model,

particularly for applications at long distances and high elevations in the atmosphere. Further, both models may be adjusted to represent mean conditions at different times of year and in diiferent geographical locations. A new method of predicting radio ray refraction at very low initial elevation angles is introduced which

utilizes both the initial value and the initial height gradient of the refractive index

over roughly the first 100 m above the earth's surface. This method, which is dependent only upon the first two radiosonde reporting levels or simple tower measure- ments of the common meteorological elements, results in a considerable improvement of the values of ray refraction predicted by the model. (Met. Abs. 12. 6-141)

--Authors' abstract.

E-616 Bolgiano, Ralph, Jr. (School of El ec. Eng. .Cornell Univ. , Ithaca), Wavelength

dependence on transhorizon propagation. Institute of Radio Engineers, N. Y. , Proceedings, 47(2): 331 -332, Feb. 1959. Fig., 7 refs. , 7 eqs. DLC --Results of

two tests made simultaneously during the winter, spring and early summer of 1957

at the Lincoln Laboratory of MIT on 417. 05 Mc and 2290 Mc are described. Tests were conducted on the transhorizon path from Round Hill, Mass. to Crawford's

Hill, N.J. During the period Feb. 11 to July 11, data were collected continuously

for intervals of 12 to 72 hrs. From closely scaled antennas, continuous signals of

3. 5 kw and 10 kw were radiated on 417 Mc and 2290 Mc, respectively. Cumulative

distributions of the signal level received on each channel during the 241 cases

(hours) investigated were then recorded. Differences in the measured hourly median for the basic transmission loss is illustrated graphically. It shows the empirical distribution of the wave length dependence, the variation of the data at substantially better than the 0. 001 level. A significant relation of this variation to

meteorological phenomena is drawn. (Met. Abs. 12. 3-100) --N. N.

E-617 Bugnolo, Dimitri S. , Correlation function and power spectra of radio links affected

by random dielectric noise . IRE Transactions on Antennas and Propagation, N. Y. , 7(2): 137-141, April 1959. 3 figs. , 11 refs. , 42 eqs. DLC -The correlation function

and corresponding power spectrum of an electromagnetic wave affected by random

dielectric noise is related to the power spectrum of the source by an extension of

the motions of time variable linear networks. It will be shown that in general, the

power spectrum of the received signal can be regarded as the output of a network

characterized by a time variable transfer function. The results are applied to a long line of sight radio link and used to predict the error in the received signal in a mean squared sense. This will be used to show that the rate of a source is

bounded such that there exists a maximum rate R given a bandwidth S and scatter- ing parameters of the atmosphere. --Author's abstract.

E-618 Bullington, K. (Bell Telephone Lab. , Inc. , Murray Hill, N. J. ), Status of tropospheric extended range transmission. Institute of Radio Engineers, Transactions

on Antennas and Propagation, Vol. AP-7(4):439-440, Oct. 1959. 2 figs. DLC--

This paper is a summary of a talk at the National Symposium on Extended Range

Transmission in Washington, D.C., Oct. 7, 1958. It summarizes the present

status of extended range tropospheric transmission with brief mention of the history, principal characteristics, nature of the mechanism and general usefulness.

Figures show the curves for estimated range for beyond horizon transmission and

the calculations involved in beyond horizon tropospheric transmission. (Met.

Abs. 13. 7-132) --E.Z.S.
153

-619 Chisholm, J.H. ; Rainville, L.P. ; Roche, J.F. and Root, H. G. , Angular diversity reception at 2290 Mc over a 188 mi path. IRE Transactions on Communications

Systems, N. Y. , 7(3):195-201, Sept. 1959. 16 figs. , 13 refs. DLC, DBS-Experiments were performed over the 188 mi Round Hill-Crawfords Hill path at 2290 Mc

to determine the feasibility of using angular diversity reception in a tropospheric

scatter system. Using a 28 ft reflector, two beams were produced with two separate feed systems. The correlation of the signals received on one or two beams

with that received on the other was determined for various spacing of the beams,

as well as for the azimuthal position of the antenna. These experiments show that

angular diversity techniques can be effective depending on the proper choice of

frequency, antenna size, and beam separation for path in the neighborhood of 200

mi in length. A substantial diversity gain can be achieved even though partial

correlation exists. These results also appear to be in good agreement with theoretical predictions for equal means and for the short periods of time applicable to obtaining reliable voice and high speed teletype communication. --Authors' abstract.

-620 Crawford, A. B. ; Hogg, D. C. and Kummer, W. H. , Studies in tropospheric propagation beyond the horizon. Bell System Technical Journal, N. Y. , 38(5): 1067-1178,

Sept. 1959. 79 figs. , 7 tables, 29 refs. , 36 eqs. DLC--This paper describes an extended series of experiments in beyond the horizon propagation on a 171 mi over- land path using 460 and 4110 Mc. The following aspects of the propagation were

investigated: the effect of antenna size on signal level and fading characteristics,

wavelength dependence, seasonal and diurnal effects, a new form of diversity re- ception, the bandwidth capability of the medium. Many of the experiments were

directed toward a better understanding of the mechanism of propagation. --Authors'

abstract.

-621 De, A.C. , Some experiments on the determination of th-,- structure and refractive

index of the lower troposphere (lowest 200 ft) over Dum Dum Airport. Calcutta.

Indian Journal of Meteorology and Geophysics, Delhi, 10(3):295-312, July 1959.

6 figs. , 3 tables, 4 refs. DWB, DLC--The results of low level (lowest 200 ft) radiosonde sounding made on certain selected dates and at certain selected hours

during the winter of 1956-57 and premonsoon season of 1957 over Dum Dum Airport

are discussed. The results indicated the formation of ducts at certain hours. The

variations of the meteorological data with the progress of night are shown in a tabular form. The radarscope observations at the corresponding hours are also

discussed. On two occasions in March and April 1957, the duct heights were abnormally high and prevailed for the whole night persisting until or even after sunrise. It is shown that these ducts extended horizontally in all directions to about

60 mi. Some radarscope observations during Feb. -March 1956 are also discussed.

On two occasions during Feb. 1956, elevated ducts were noticed. These prevailed

for the whole night. The attenuation produced by the appearance of thick fog over

the station and its masking effect on the ground clutters are also discussed. (Met.

Abs. 11. 2- 168) -Author's abstract.

-622 Deam, A. P. , An expendable atmospheric radio refractometer. Texas. Univ.

Electrical Engineering Research Lab. , Contract Nonr 375(08), Report No. 108,

May 15, 1959. 9 p. plus appendices, 16 figs. , 3 refs. , 24 eqs. DWB (M84

T355r)--This report describes a device which has been designed to measure atmospheric index of refraction profiles at a frequency of 403 Mc/s. It is a prototype

instrument and should be capable of ejection from an aircraft as well as elevation

with a balloon. Transmitted frequency is received at a receiver whose recorded

output is relative radio index of refraction. This instrument has been successfully

tested in a balloon flight to elevations of the order of 60,000 ft. (Met. Abs.

12. 10-134) -Author's abstract.
154

E-623 de Belatini, P.C. M. , Inadequacy of scatter mechanism in tropospheric radio propa - gation. Nature, London, 184(4698): 1558-1559, Nov. 14, 1959. 2 figs. , 3 refs.

DLC--In this note author concludes that a scatter mechanism is not principally re- sponsible for tropospheric propagation and this leads to the question of a replacement theory. His unpublished theory is briefly discussed, which shows that the

main features of tropospheric propagation can be adequately explained, both qualitatively and quantitatively in terms of toroidal thermal motions in the atmosphere

which are known as "Be'nard cells". --E. K.

E-624 Denisov, N. G. and Zverev, V.A. , Nekotorye voprosy teorii rasprostraneniia voln

v sredakh s sluchainymi neodnorodnostiami. (Some theoretical problems of wave

propagation in media with weak inhomogeneities. ) U.S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 2(4):

521-542, 1959. 31 refs. , 90 eqs. DLC--On the basis of international literature

the author presents a detailed review of the theory of wave propagation in a ran- domly inhomogeneous medium. The particular problems treated are those of 1)

approximation of geometrical optics, 2) method of even inhomogeneities, 3) diffraction of waves by an irregular screen, and 4) scattering of waves by weak in- homogeneities. --G.T.

E-625 Doherty, Lome H. (Radio and Elect. Div. , Nat'l. Res. Council, Ottawa, Canada),

Scatter propagation experiment using an array of six paraboloids . IRE Transactions on Antennas and Propagation, 7(4):419-428, Oct. 1959. 8 figs. , 5 tables,

20 refs. , 18 eqs. DLC --Using an antenna system whose aperture could be varied

in 4 ft steps between 4 and 24 ft, aperture to medium coupling loss measurements

have been made on a 2720 msec, 216 mi path. These measurements reveal an in- trinsic variability in the scattering mechanism which is not accounted for in most

current theories. Diversity and fading rate measurements were also made. A

simple mathematical model of the diffracted field yields calculated values of the

normal component of the wind which agree well with the measured wind. Calculated and measured values of fading rate are also seen to be in good agreement.

An estimate is made of the turbulent wind velocity. --Author's abstract.

E-626 Doherty, L.H.and Neal, G. A. , A 215 mile 2720 Mc radio link. IRE Transactions on Antennas and Propagation, N. Y. , 7(2):117-126, April 1959. 16 figs. , table,

4 refs. DLC --The results from the operation of a 215 mi, 2720 Mc radio link are discussed. The link was opened for a period of 20 months. The yearly median

signal level was 79 db below free space with a seasonal variation between 12 and

14 db in the hourly medians. If attention is confined to a single season, the

hourly medians have a log normal distribution. No diurnal variation was observed.

Probability distributions of signal amplitude based on 30 sec samples were most

commonly Rayleigh although some significant departures from this law did occur. A study of the time variation of the 30 sec median shows the standard deviation

of these medians 5 min apart to be about 1 db, and 30 min apart to be 2. 6 db.

The same type of analysis is also performed on the hourly medians. A diurnal

variation is observed in the fading, with the midafternoon rate being almost twice

that recorded during the early morning. Pulse distortion and meteorological cor- relations are discussed quantitatively. --Authors' abstract.
155

Dolukhanov, M.P. , O kharaktere iskazhenii siqnalov v sisteme telefonii na odnoY

bokovoi polose v troposfernykh liniiakh sviazi . (Nature of signal distortions in a single sideband telephonic system for a tropospheric link.) Elektrosviaz', Moscow,

13(11): 12-16, Nov. 1959. 7 figs. , 5 refs. , 24 eqs. Transl. into English in Telecommunications, N. Y. , No. 11:1180-1188, 1959. DLC -Distortions arising during

propagation of signals in a steady state tropospheric link are investigated theoretically. An ideal case of the interference of two beams is examined and then extended to the real troposphere. It is found that no transient distortions occur during

propagation in the SSB telephonic transmission. The sole types of distortions are fading and Doppler shift. --Transl. of author's abstract. -R. M.

du Castel, F. ; Misme, P. and Voge, J. , Reflexions partielles dans 1' atmosphere

et propagation a qrande distance. Troisieme partie. Reflexion en milieu inhomogene . (Partial reflections in the atmosphere and long range propagation, Pt. 3, Reflection in inhomogeneous medium.) Annales des Telecommunications, Paris,

14(1/2): 33-40, Jan. /Feb. 1959. 10 figs. , ref. , eqs. DLC -After establishing some

general results concerning the reflection of a plane wave upon an irregular surface,

authors investigate a real case of emitter and receiver at a definite distance. Reflected field is divided into a spicular relection and a diffuse relection component.

Both components have peculiarities (mean amplitude, distribution laws, direction,

phase, reflecting surface) complying with very different laws. These are specified

in the instances of slightly and highly contorted surfaces. (See refs E-542 735

786, 772, 715). (Met. Abs. 14. 1-56)»A. V.

Feinberg, E.L., Propagation of radio waves along an inhomogeneous surface.

Nuovo Cimento, Bologna, Ser. 10, Supplemento to 11(1):60-91, Jan. 1959. 13 figs.,

26 refs. , eqs. DLC—In the study a fundamental integral equation is presented

which gives a useful and convenient basis for treating propagation of radiowaves,

both for flat and for spherical earth, for homogeneous or inhomogeneous surfaces.

Reference is made to a particular combination of inhomogeneity and corrugation for spherical earth on the basis of this equation. The paper reviews systematically

the basic ideas and the main results of the method. —E. K.

Finney, R.G. , Short time statistics of tropospheric radio wave propagation.

Institute of Radio Engineers, N. Y. , Proceedings, 47(l):84-85, Jan. 1959. 3 refs.,

2 eqs. DLC --An experimental investigation of short time statistics which characterize beyond the horizon tropospheric propagation, is briefly summarized. The

paper concludes that the envelope amplitude was frequently Rayleigh disturbed,

however, enough non-Rayleigh results were obtained to suggest other processes.

--E.K.

Furutsu, Koichi, Wave propagation over an irregular terrain. Pt. 3. diagrams of

ridge and precipice effects on ground waves. Japan. Radio Research Laboratories,

Journal, 6(23): 71 -102, Jan. 1959. 11 figs. , eqs. DBS -The formulas of field

strength over an irregular terrain, obtained on a rather general condition in previous papers (see E-459) are here used for the estimation of the ridge and pre- cipice effects on ground waves. The results are displayed in diagrams for practical use. Most of these diagrams have reference to cases where propagation distances over the media adjacent to a ridge or precipice are so long that the top or edge of the boundary is out of sight from the transmitter and the receiver. The

rest concern cases where the propagation distances over the first or final section

of inhomogeneous earth are sufficiently short. --Author's abstract.
156

E-632 Gusiatinskii, I. A. , Shirina polosy i moshchnost' perekhodnykh pomekh pri radiosviazi rasseianiem v troposfere . (Bandwidth and power of transient interference

in radiocommunication by tropospheric scattering. ) Elektrosviaz', Moscow, 13(4):

3-12, April 1959. 5 figs. , 7 refs. , 56 eqs. Transl. into English in Telecommunications, N. Y. , No. 4:355-367, 1959. --The bandwidth has been determined for signals transmitted with permissible magnitude and probability of distortion of the

amplitude spectrum; formulas are obtained for the calculation of the power of tran- sient interference arising from multiple ray propagation in multi-channel FM systems. --Author's abstract.

E-633 Hachenberg, O. and Schachenmeier, R. , Die Refraktion von dm-Wellen in der

Troposphere. (Refraction of decimeter waves in the troposphere. ) Hochfrequenztechnik und Elektroakustik, Leipzig, 68(1): 1-7, May 1959. 7 figs. , 3 tables,

3 refs. , 17 eqs. DLC--By means of receiving apparatus for 20 cm waves refraction

is measured on the basis of nearness to the horizon. From the cover curve the

moment at which the middle of the sun passes the line of the horizon is derived,

and, for that purpose, the zenith distance is calculated on the basis of the known

position of the sun. Refraction is thus determined. Refraction values are obtained which are approximately 40% greater than the optical. Moreover, the scattering area is considerably greater. By way of proof, the radiation path is calculated from known quantities of the troposphere which are taken from synoptic re- cords. Refraction is calculated from this. The proposed calculation procedure

is applicable to a spherical troposphere with any type of stratification. The measured and computed refraction angles were compared for 43 sunrises and sunsets

in 1956. --Transl. of authors' abstract-R. M.

E-634 Hartman, W. and Wilkerson, J. , Path antenna gain in an exponential atmosphere.

U.S. National Bureau of Standards, Journal of Research, Sec. D, Radio Propagation, 63(3): 273-1286, Nov. /Dec. 1959. 11 figs. , 10 refs. , numerous eqs. DLC--

The problem of determining path antenna gain is treated here in greater detail than

previously. The method used here takes into account, for the first time, the ex- ponential decrease of the gradient of refractive index with height, and a scattering cross section inversely proportional to the 5th power of scattering angle. Results

are given for all combinations of beamwidth and path geometry, assuming that at- mospheric turbulence is isotropic. The result appears as a function of both of the

beamwidths, in addition to other parameters, and thus the loss in gain cannot be

determined independently for the transmitting and receiving antennas. The values

of the loss in gain are generally lower than the previous estimates for which a comparison is possible. --Authors' abstract.

E-635 Hathaway, S. D. and Evans, H. W. , Radio attenuation at 11 Kmc and some implications affecting relay system engineering . Bell System Technical Journal, N. Y. , 38(1): 73-97, Jan. 1959. 21 figs. , 10 refs. , eqs. DWB--Radio waves at 11 kmc

are attenuated by rain. In order to derive rules for engineering radio relay systems at 11 kmc, a one year experiment was conducted in a region of frequent heavy

rainfall. The attenuation of paths 27 and 12 mi long was measured, together with

rainfall at 2 mi intervals along the paths. The instrumentation and the test results

are described, and some implications related to systems engineering are pointed

out. —Authors' abstract.

E-636 Hay, D. R. , Apparent correlation between tropopause height and long distance

transmission loss at 490 Mc. Institute of Radio Engineers, N. Y. , Proceedings,

47(6): 1144-1145, June 1959. 2 figs. , 10 refs. DLC--A short term experiment has
157

been carried out in central Ontario to examine 490 Mc transmission over a 640 mi

path. Results indicate that the periods of relatively stable transmission and

higher loss were concurrent with a low tropopause, and periods of relatively un- stable transmission and lower loss occurred when the troposphere was high.

--E.K.

Hay, D. R. (Dept. Physics, Univ. Western Ontario) and Poaps, G. E. , Frontal

perturbation of a troposphere scatter path. Canadian Journal of Physics, Ottawa,

37(11): 1272-1282, Nov. 1959. 5 figs. , table, 22 refs. DWB, DLC--A 2 yr study

of 500 Mc/s radio transmissions over an 85 mi path near Ottawa has shown that

the signal fading rate rises well above the diurnal maximum when the transmission path is perturbed by a weather front. The fading rate reaches a maximum

when the upper boundary of the frontal zone is 3000 ft above the center of the

radio path, and the fading rate remains high as long as any part of the frontal zone is between the surface and 3000 ft. A similar relationship between frontal

position and signal fading rate is found for Arctic, Maritime, or Polar fronts in

the Ottawa area, but the Arctic fronts provide the clearest definition. There is some indication that high fading rate also may be associated with horizontal

layers of contrasting humidity at low levels in the troposphere. (Met. Abs.

12. 9-103)--Authors' abstract.

Herbstreit, J. W. and Rice, P.L., Survey of Central Radio Propagation Laboratory

research in tropospheric propagation. NBS Technical Note, No. 26, PB 151385,

Sept. 1959. DBS--This report summarizes and abstracts publications concerned

with the National Bureau of Standards tropospheric propagation research program

dating back to the formation of the Central Radio Propagation Laboratory. Some

technical papers are reproduced here as supplements to this report and excerpts

from some of the longer technical reports are also included. (Met. Abs. 10. 2-174)

--Authors' abstract.

Hirao, Kunio; Akita, Kin-Ichiro and Shiro, Isao, Vertical distribution of the

scattering parameter for radiowave . Japan. Radio Research Laboratories, Journal,

6(27): 595-601, July 1959. 6 figs. , table, 4 refs. Japanese version in its Review,

5(21):260-263, Oct. 1959. DBS--By means of both kytoon and refractive index var- iometer, the scattering parameter for radio wave in the layer below 1000 m above

the ground was measured at the Tateno Aerological Observatory during Sept. 1957

and Nov. 1958. The observational results show that the vertical distribution of

the scattering parameter is proportional to -2/3 power of the height and that it has seasonal variation. --Authors' abstract.

Hogg, D.C., Effective antenna temperature due to oxygen and water vapor in the

atmosphere. Journal of Applied Physics, 30(9): 1417-1419, Nov. 1959. 5 figs. , 7 refs. DLC --Calculations of the effective noise temperature at the terminals of a high gain antenna due to oxygen and water vapor in the atmosphere are given

for the frequency range 0. 5 to 40 kmc. In the 1 to 10 kmc band, the effective

temperature increases from about 3° to 100°K at the zenith angle is increased

from 0° to 90°. Calculated values of the total attenuation through the atmosphere

are given. --Author's abstract.
158

E-641 Jehn, K.H. , Use of potential refractive index in synoptic scale radio meteorology. Journal of Meteorology, Boston, 17(3): 264-269, June 1960. 8 figs. , 3 refs. , 6

eqs. DWB, DLC. Also issued as: Texas. Univ. Electrical Engineering Research

Lab. , Contract AF 19(604)-2249, Report No. 6-29, Sept. 15, 1959. 10 p. 8 figs. , 3 refs. , 6 eqs. DWB (M94. 7 T355r)--The concept of potential refractive index is

examined in the light of earlier work and of the present emphasis on synoptic scale

radio meteorology. A new potential refractive index is defined and illustrated. It is concluded that the new parameter has operational utility in long range microwave

radio and radar transmission, as well as in refractive index mapping. An example

is worked out and illustrated with synoptic charts, refractive index charts, cross

sections and radiosonde refractive index diagrams for the cold wave of Feb. 19,

1952 in Northern and Central Plains of the U.S. (Met. Abs. 12. 2-92)--Author's

abstract and M. R.

E-642 Kalinin, A. I. , The coherence theory of long distance tropospheric propagation of

ultra short waves . Telecommunications, N. Y. , No. 6:621-634, 1959. 4 figs. , 6 refs. , 35 eqs. Transl. of Russian article in Elektrosviaz', Moscow, No. 6:41-49,

1959. DLC --This article gives the results of a theory of long distance tropospheric

propagation of ultra short v/aves based on the hypothesis of coherent reflection of

waves from stratified inhomogeneities in the troposphere and on the exponential

dependence of the dielectric constant of air on height above the earth's surface.

A comparison of the theoretical and experimental results is also made. --Author's

abstract.

E-643 Kaner, E. A. , K teorii rasprostraneniia voln v srede so sluchaimymi neodnorodnostiami. (Theory of the propagation of waves in a medium with random inhomogeneities. ) U. S. S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh

Uchebnykh Zavedmii, Radiofizika, 2(5):827-829, 1959. Table, 4 refs. , 14 eqs.

DLC --The author analyzes the effect of fading and changes in phase velocity in

the average field due to scattering by random irregularities. The method of small

perturbations in a form proposed by Lifshits, Kaganov, and Tsukernik is used. It is shown that fading of the average field due to scattering by small irregularities

obeys the Rayleigh law, while in the case of large scale irregularities fading is

determined not only by amplitude fluctuations, but also by fluctuations in the

phase of the radiated field. --R. M.

E-644 Kaner, E. A. and Bass, F. G. , K statisticheskoi' teorii rasprostraneniia radiovoln

nad ideal 'no provodiashchei ploskost'iu . (Statistical theory of radio wave propagation over an ideally conducting plane.) Akademiia Nauk SSSR, Doklady, 127(4):

792-795, 1959. 6 refs. , 14 eqs. DWB, DLC -The authors calculate the statistical characteristics of an electromagnetic field propagated in a medium with small

random fluctuations <5f in permittivity €- (^ ) + <$£ over an ideally conducting

half space. The interface is assumed to be plane, and the medium over the sur- face to be statistically regular. The radiation source (a dipole with moment d) is

situated at a height z Q above the interface. The origin of the coordinates coincides with the projection of the dipole on the interface plane, the axis Oz runs along a straight projection connecting the dipole with the point of observation r (L.O, z). The treatment is limited to large scale fluctuations, when the characteristic correlation radius / is large in comparison with wavelength X . --R. M.
159

Kaner, E. A. and Bass, F. G. , Rasprostranenie elektromaqnitnykh voln v srede so sluchainymi neodnorodnostiami nad ideal'no provodiashchei ploskost'iu . (Propagation of electromagnetic waves in a medium with random inhomogeneities

over an ideally conducting surface. ) U.S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenu, Radiofizika, 2(4): 553-564, 1959.

7 refs. , 48 eqs. DLC --Elaboration of a theory of the propagation of electromagnetic waves in a statistically homogeneous medium over an ideally conducting sur- face. The authors calculate the basic statistic characteristics (mean field, meansquare fluctuations of amplitude and phase) and their dependence on radio wave

frequency and polarization, distance, and height of the receiving and transmitting

antennas. The effect of a sharp increase in fluctuations near interference minimums of the mean field and on the edge of the first lobe is also investigated.

(See E-603)--Transl. of authors' abstract.- R. M.

Keary, T. J. , International conference on radio wave propagation. Institute of

Radio Engineers, N. Y. , Proceedings, 47(6): 1147-1148, June 1959. DLC -A brief

summary of the conference which was held on Oct. 6-11, 1958 at Liege, Belgium.

A total of 55 papers was presented. Major discussions concentrated on the fol- lowing subjects: 1) distant (beyond the horizon) propagation of ultra short radio

waves and the application to radio communications; 2) ionospheric investigations,

particularly those using back scatter sounding techniques; 3) forward scattering

of radio waves from the ionized trails of meteors; 4) propagation of low frequency

radio waves. Some of the papers which were considered as significant by the

author are summarized. --E. K.

Kummer, W. H. , Sweep frequency studies in beyond-the-horizon propagation. IRE Transactions on Antennas and Propagation, 7(4):428-433, Oct. 1959. 9 figs. , table, 6 refs. , eq. DLC --This paper considers the bandwidth characteristics of

the propagating medium in tropospheric beyond-the-horizon propagation. To study

this problem, a frequency sweep experiment was performed over a 171 mi experimental circuit. A 4. 11 kmc transmitter was frequency modulated at 1000 cps rate over a 20 Mc band. The receiver was swept nonsynchronously over the same band

at a 30 cps rate. The resultant pulses were displayed on an oscillograph and

photographed at the rate of one frame every 2 sec. The experiment used a 28 ft transmitting antenna and 8-, 28- and 60 ft receiving antennas. Sequences of

selected sweep frequency pictures are shown for various antenna combinations

and transmission conditions. The bandwidths from the experiment are compared

with a calculation based on the common volume geometry. Photographs of signals

received simultaneously from a twin feed horizontal diversity system are also

shown and discussed. --Author's abstract.

LaGrone, A.H. , Report of the TASO Committee 5.4 on Forecasting Television

Service Fields, IRE National Convention Record, N. Y. , 7:159-164, 1959. 9 refs.

DLC --The propagation of VHF and UHF television signals over a spherical, irregular surface such as the- Earth, is examined theoretically and experimentally and

the principal factors evaluated. Among the more important factors found are meteorology, frequency, terrain, and the absorbing effect of vegetation. These are

all included in a new method suggested for forecasting the service fields of television stations. The new method is compared with field measured cases with

good results. --Author's abstract.
160

E-649 Lu, Pao-wei, Theory of forward scatter propagation of ultrashort radio waves.

Scientia Sinica, Peking, 8(7):761-780, 1959. Fig., 5 refs. , 91 eqs. DLC--The

author considers present theories of tropospheric and ionospheric propagation of

UHF waves beyond the horizon imperfect, namely, that in tropospheric propagation, scattering by inhomogeneities due to turbulence is the chief mechanism,

and that insufficient attention has been given to the gradient of the dielectric constant with altitude. Scattering in the ionosphere is examined only as affected by

turbulence inhomogeneities and the effect of meteor trails is neglected. Results

obtained by applying the statistical theory of turbulence are given separately for

the troposphere and for the ionosphere. --R. M.

E-650 McDonald, D.J. and Frost, C.E. , Quebec -Labrador tropospheric scatter radio

system. Engineering Journal, Montreal, 42(4):43-57, April 1959. 9 figs. , ref. DLC --Report on the engineering and construction of a scatter radio system to provide telephone and miscellaneous communication services to Schefferville

and Goose Bay and to other locations in Northern Quebec and Labrador. Particular

emphasis is on the broad planning of the system and on the construction aspects.

Pt. I deals with the engineering aspects of the system; Pt. II deals with the design and construction of buildings, towers, roads, etc. --Authors' abstract.

E-651 McGavin, Raymond E. and Maloney, Leo J. , Study at 1046 megacycles per sec- ond of the reflection coefficient of irregular terrain at grazing angles . U.S. National Bureau of Standards, Journal of Research, Sec. D, 63(2):235-248, Sept./

Oct. 1959. 13 figs. , 2 tables, 25 refs. , 3 eqs. DWB, DLC--An experimental

determination of the reflection coefficient over rough terrain is reported. The re- flected signal received over rough terrain is considered to be made up of two components, one that is a specular component and the other a Rayleigh distributed

component. Where one terminal is low, the Rayleigh component is considered

to be small with respect to the specular component but increases in relative magnitude as the height of the lower terminal increases. A terminal height is reached

where the specular component is no longer significant, and the reflected energy is

essentially Rayleigh distributed. A terminal height is quickly reached above

which the mean value of the reflected energy is relatively constant, of a low val- ue, and independent of the grazing angle. (Met. Abs. 14. 4-113)--Authors* abstract.

E-652 Men', A.V. , K voprosu o korreliatsii fliuktuatsii'SVCh radiovoln pri rasprostranenii v neodnorodnoi srede. (Problem of the correlation of fluctuations of shf

radio waves propagated in an inhomogeneous medium.) U.S.S. R. Ministerstvo

Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika,

2(3):395-399, 1959. 3 figs. , 7 refs. , 14 eqs. DLC--The longitudinal correlation

of fluctuations in the line of sight is determined. Expressions are derived for cor- relation functions of phase and amplitude fluctuations at distributed points oriented arbitrarily with respect to the source. --Transl. of author's abstract-R. M.

E-653 Men', A.V. ; Braude, S. la. and Gorbach, V.I. , Eksperimental'noe issledovanie

fazovykh fliuktuatsiY santimetrovykh radiovoln nad morsko'i poverkhnost'iu. (Experimental investigation of phase fluctuations of centimeter waves propagated over

the sea surface. ) U.S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 2(6):848-857, 1959. 11 figs. , 14 refs.,

5 eqs. DLC --Report on results of experimental measurement of the fluctuation of

phase fronts during the propagation of vertically polarized radio waves over the sea surface. The frequency employed was 3000 Mc/s and the experiments were
161

carried out under various meteorological conditions during July - Sept. and Oct. - Dec. , over a fixed sea route having a length of 33 km. The differential method of

measurement was employed, in which the fluctuations of the phase differences of

the signals received by spaced antennas were employed to determine the intensity

and the decorrelation of the phase fluctuations at various points of the wave front. Fixed transmitting and receiving antennas were used. In order to reduce the effect

of the shore refraction, the receiving systems were situated at 15 to 20 meters

from the shore with distances of 2, 5, 10, 30 and 100 meters separating them from

the first (reference) antenna. The error in the measurement of the phase difference

fluctuations was less than + 1°, even when the amplitude of the received signals

varied as much as 60 db. Results of measurements are shown in 11 figures.

--R.M.

E-654 Men', A. V. ; Gorbach, V.I. and Braude, S.Ia. , Vliianie poverkhnosti razdela na fliuktuatsii radiovoln. rasprostraniaiushchikhsia v neodnorodnoY srede.

(Effect of an interface on the fluctuations of radio waves propagated in an inhomogeneous medium.) U. S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh ZavedeniY, Radiofizika, 2(3):388-394, 1959. 4 figs. , 10 refs. , 16 eqs. DLC--The authors obtain approximate expressions for determining amplitude and phase fluctuations in the line of sight and beyond the horizon in connection with propagation in an inhomogeneous medium over a plane interface. It is shown that there is substantially no dependence of the intensity of fluctuations on distance, wave length, and altitude in comparison with the free space case. Computed values are compared with experimental data. --Transl. of authors' abstract. -R.M.

E-655 Millington, G. , Study Group IV. around wave propagation. V. tropospheric propagation. Point to Point Telecommunications, Chelmsford, England, 4(l):49-55,

Oct. 1959. DLC--This is a brief report on functions and activities of the study

groups IV and V of the International Radio Consultative Committee (C.C.I. R.),

and includes some aspects and problems of current interest. Study Groups IV

and V are now united into the single group No. V. (IV will be the study group for space communication). --W. N.

E-656 Nishikori, Kiyoshi; Takahira, Akira and Irie, Hiromi, Microwave propagation

over the sea beyond the line of sight . Japan. Radio Research Laboratories,

Journal, 6(23):57-70, Jan. 1959. 15 figs. , 2 tables, 5 refs. DBS--The experiments were conducted at a frequency of 9375 Mc/s along the Sea of Kashima in

1955-57, the waves being transmitted by Inubo Radio Wave Observatory. This

paper contains an analysis of the propagation mechanism and associated meteorological phenomena. Quantitative values are obtained for attenuation and fading

in the duct propagation by the use of the ray tracing method and Fresnel's theoretical formulas of reflection and penetration. M curve models are determined for

all seasons. Problems of forecasting duct propagation conditions are also discussed. --G.T.

E-657 Norton, K. A. , Recent experimental evidence favoring the ykj_ (p) correlation

function for describing the turbulence of refractivity in the troposphere and stra- tosphere. Journal of Atmospheric and Terrestrial Physics, London, 15(3/4):206-

227, Oct. 1959. 7 figs. , 4 tables, 21 refs. , 15 eqs. DLC--The purpose of this

paper is to show that although atmospheric turbulence is extremely variable, the

log normally modified p'K-i (p") correlation function may be used to describe the
162

characteristics of refractivity variations as exemplified in three independent kinds

of measurement: 1) direct measurements of the variations of n with time at a fixed

location made with a refractometer, 2) measurements of variations with time of the

phase of a radio wave received over a line of sight path, and 3) measurements of

the received power of radio waves scattered in the forward direction to a receiving

point beyond the radio horizon of the transmitter. --E. K.

E-658 Norton, Kenneth A. , System loss in radio wave propagation. U.S. National

Bureau of Standards, Journal of Research, Sec. D, 63(l):53-73, July/Aug. 1959.

14 figs. , 6 tables, 33 refs. , 79 eqs. DLC, DWB--A summary is presented of the

ways in which the concept of system loss and the closely related concepts of

transmission loss, basic transmission loss, propagation loss, and path antenna

gain may be used for precise, yet simple, descriptions of some of the characteristics of radio wave propagation which are important in the design of radio systems. Definitions of various terms associated with the concept of system loss

are given which introduce a greater flexibility into its use without any loss in precision. It is shown that the use of these added terms and concepts makes feasible

the extension of the use of this method of description to any portion of the radio

spectrum. A more general formula for the system loss is given which may be used

for antennas with an arbitrarily small separation. Using this formula, it is shown

that the system loss between small electric or magnetic dipoles separated by a distance d <T< \. can be made arbitrarily small even though the individual anten- nas have large circuit losses. Formulas are developed for the percentage of time

that a desired signal is free of interference, and these are used to demonstrate

methods for the efficient use of the spectrum. In particular, contrary to general

belief, it is shown that efficiency is promoted by the use of high power and high

antennas and, in the case of a broadcast service, sufficiently small separations so that there is appreciable mutual interference. An analysis is made of the var- iance of the path antenna gain in ionospheric scatter propagation. Methods are given for the calculation of the transmission loss for the ground wave and tropospheric scatter modes of propagation through a turbulent model atmosphere with an

exponential gradient. Examples of such calculations are given which cover a wide

range of frequencies and antenna heights. Finally, examples are given of the ex- pected range of various tropospheric point-to-point scatter systems such as an FM

multichannel teletype system, a television relay or an FM broadcast relay.

--Author's abstract.

E-659 Norton, Kenneth A. , Transmission loss in radio propagation. Pt. 2 . U.S. National

Bureau of Standards, Technical Note, No. 12, June 1959. 118+ p. 51+ figs.,

tables, 73+ refs., eqs. Appendix I-III following p. 118. DLC, DBS --In an earlier

report with this title, the concept of transmission loss was defined and its advantages explained. In this report a survey will be made of the transmission losses

expected for a wide range of conditions, i. e. , for distances from 10 to 10, 000

statute miles; for radio frequencies from 10 kc to 100,000 Mc; for vertical or horizontal polarization; for ground waves, ionospheric waves, and tropospheric

waves; over sea water or over land which may be either rough or smooth; and for

various geographical and climatological regions. --Author's abstract.

E-660 Obukhov, A. M. (Inst, of the Physics of the Atmosphere, Acad, of Sciences, Moscow), Scattering of waves and microstructure of turbulence in the atmosphere . Journal of Geophysical Research, Wash. ,D.C, 64(12) -.2180-2187, Dec. 1959.

7 figs. , 20 refs. , 4 eqs. DLC--The paper deals with a brief survey of the theory

of scattering of waves by turbulent inhomogeneities. Experiments on the study of
163

scattering phenomena of sound by turbulence in the surface layer of the atmosphere

are discussed. These experiments were carried out to obtain some information on

the turbulent spectrum; their results are compared with the data of meteorological

measurements in the surface layer. Applying the method of scattered radio waves

to the study of turbulence in the ionosphere is discussed. (Met. Abs. 11F-101)

--Author's abstract.

E-661 Plank, V. G. , Convection and refractive index inhomoqeneities. Journal of Atmospheric and Terrestrial Physics, N. Y. , 15(3/4): 228-247, Oct. 1959. 10 figs. , 2

tables, refs. DLC --Certain observations and theories in the field of cumulus con- vection are reviewed and an attempt has been made to integrate them into a more

or less comprehensive picture. The picture was then interpreted in terms of refractive index structure. --Author's abstract.

E-662 Ponomarenko, L.M., Opredelenie napriazhennosti elektromaqnitnogo polia v diapazone ukv v oblasti qluhokofteni za schet koqerentnoqo rasseianiia v atmosfere.

(Determination of USW electromagnetic field intensity due to coherent atmospheric

scattering in the deep shadow region. ) Radiotekhnika i Elektronika, Moscow,

4(6):930-935, June 1959. Fig. , 4 refs. , 17 eqs. Transl. into English in Radio

Engineering and Electronics, N. Y. , 4(6):29-37, 1959. DLC-The process of long

distance USW propagation due to coherent scattering in the troposphere is analyzed

theoretically using the parabolic equation method of Leontovich and Fok instead of

the more complicated normal wave method proposed by Carroll and Ring. A characteristic equation of the eigenvalues of the dependence of the refractive index on

height for a bilinear profile of the refractive index is presented. Numerical values

are derived for the field strength in a region of deep shadow for a wavelength of

6 m, a transmitter and receiver height of 300 m, an antenna directivity coefficient

of 1, and a transmitted power of 1 kw. The results obtained agree fairly well with

those of Carroll and Ring, the height of the transition layer obtained being 8.45

km as against 9. 3 km obtained by Carroll and Ring. --R. M.

E-663 Prosin, A. V. , K raschetu perekrestnykh iskazhenii pri mnoqoluchevom rasprostranenii radiovoln. (Contribution to the calculation of intermodulation crosstalk

in multipath transmission of radio waves. ) U. S. S. R. Ministerstvo Vysshego

Obrazovaniia, Nauchnye Doklady Vysshei Shkoly; Radiotekhnika i Elektronika,

No. 1:53-61, 1959. 4 refs. , 19 eqs. --On the basis of the correlation theory of

stationary random processes, the author works out a method of calculating the

power of intermodulation crosstalk due to multipath propagation or mismatch and

irregularities in multichannel FM radio relay links with frequency division. The

formulas derived are correct for (1) two-path propagation with different amplitude

relationships between the direct and the reflected wave, and (2) multipath propagation when the intensity of the reflected signals is low in comparison with the

main signal. The calculation formulas also make it possible to determine intermodulation due to reflections in the feeder. —Transl. of author's abstract. -R. M.

E-664 Prosin, A.V. , O vliianii statisticheskikh kharakteristik turbulentnoi troposfery na rasseiannoe rasprostranenie ul'trakorotkikh voln. (Influence of statistical

characteristics of the turbulent troposphere on the scatter propagation of ultrashort

waves.) U.S.S. R. Ministervstvo Vysshego Obrazovaniia, Nauchnye Doklady Vysshei Shkoly, Radiotekhnika i Elektronika, No. 1:43-52, 1959. 4 figs. , 12 refs. , 24 eqs. --The author presents a generalized expression for the class of correlation

functions of the irregularities of the dielectric constant of air which is correct for

the anisotropic and the isotropic turbulence of the troposphere. The correlation
function is written as follows:

164

2(1 P) (Ssv v

,_P «/•)( At)- ^f^- (y-)P KP (—)

o Where B~ ( Z9

) is the correlation function of the dielectric constant; ( A. £ ) is

the intensity of fluctuation of the dielectric constant of air; is the extent of

turbulent irregularities; K

p

is the modified Bessel function (MacDonald function);

P is the gamma function; and P is the distance between two points in a turbulent flow in which fluctuations of the dielectric constant are considered. The

author analyzes the dependence of the effective cross section of scattering (scattering coefficient) on the form of correlation function and energy spectrum of tur- bulent irregularities of the troposphere on the extent of irregularities and on a number of other parameters. Results of different scattering theories are compared

on the basis of the aforementioned correlation function. --R. M.

E-665 Prosin, A.V.and Gubskii, V.F. , K teorii raznesennoqo priema pri dal'nem troposfernom rasprostranenii UKV. (Contribution to the Theory of diversity reception in

extended range tropospheric propagation of ultrashort waves. ) Radiotekhnika,

Moscow, 14(5):23-33, May 1959. 4 figs. , 6 refs. , 47 eqs. Transl. into English

in Radio Engineering, N. Y. , 14(5):31-44, 1959. -On the basis of the theory of the

scattering of radio waves by turbulent irregularities of the troposphere, the authors

consider the effect of the parameters of tropospheric scatter links and parameters

of the scattering medium on the correlation of received signals with space and fre- quency diversity. The formulas and curves obtained for correlation functions make

it possible to calculate the necessary separation of receiving points in planning

transhorizon communication systems. Transl. of authors' abstract. -R. M.

E-666 Prosin, A.V.; Levshin, LP. and Slobodeniuk, G. I. , Eksperimental'noe issledovanie dal'neqo tr^posfernogo rasprostraneniia ukv pri sdvoennom prieme. (Experimental investigation of long distance tropospheric propagation of USW using space

diversity reception. ) Radiotekhnika, Moscow, 14(10):3-14, Oct. 1959. 17 figs. , table, ref. , 6 eqs. Transl. into English in Radio Engineering, N. Y. , 14(10):1-18,

1959. DLC--The results of experimental studies of the statistical characteristics

of signals transmitted at 3000 Mc over a 275 km path are discussed and compared

with theory. The signals were received on a two element antenna, (high-gain and

a low gain), positioned normal to the path, and recorded simultaneously on a loop

oscillograph and a double track electronic oscilloscope. The mean field strength

at the receivers, losses in antenna gain, the unidimensional and dual dimensional

distribution of instantaneous signal values for short periods of time, the correlation coefficient describing the degree of association between rapid signal fading

at both elements of the antenna, the correlation coefficient when the signals were spaced in time, the velocity of rapid fluctuations of the field level beyond the

horizon, and the distribution of pulse durations are examined individually. The

results obtained may be used to set up radiocommunication links using long range

tropospheric propagation of USW, being valid for a 10 cm wave length and a 275

km path. Good agreement between theoretical and experimental values, however,

permits extrapolation of the results for other frequencies and distances within cer- tain limits. --R. M.
165

Rice, P.L. ; Longley, A. G. and Norton, K. A. , Prediction of the cumulative distribution of ground wave and tropospheric wave transmission loss . U. S. National

Bureau of Standards, Technical Note, No. 15, July 1959. 81 p. 44 figs. , 7 tables,

refs. , eqs. DLC, DBS--A method for predicting the cumulative distribution with

time of transmission loss at frequencies above 10 megacycles per second over path

of arbitrary length, is described. The method makes use of available information

about terrain profiles and surface meteorological data, and is based on the CRPL

radio standard atmospheres, in which the radio refractive index decreases linearly

with height for the first kilometer above ground, and the decreases exponentially

with height. Discussion of the theoretical basis for this formula and a demonstration of its accuracy by comparison with experimental data are reserved for later

parts of this report. --Authors' abstract.

Rodak, M.I. and Frantsesson, A. V., On the use of turbulence theory to investigate the scattering of radio waves from wandering inhomoqeneities . Radio Engineering and Electronics, N. Y. , 4(3):66-74, 1959. 6 refs. , 16 eqs. Transl. from

Russian in Radiotekhnika i Elektronika, Moscow, 4(3):398-403, March 1959.

DLC --Scattering of radio waves from particles, the motion of which can be described in terms of Kolmogorov and Obukhov's turbulence theory, is investigated.

The conditions are clarified, which make it permissible to evaluate the correlation

function (the spectrum) of the scattered field (of the components of its amplitude)

and the correlation function (the spectrum) of its intensity, while assuming the

velocity of the scattering centers to be constant. --Authors' abstract.

Semenov, A. A. and Karpeev, G.A. Investigation of rapid fading of radio signals at medium distances along the Earth's surface. Radio Engineering and Electronics, N. Y. , 4(2):43-54, 1959. 5 figs. , 12 refs. , 6 eqs. Transl. from Russian

in Radiotekhnika i Elektronika, Moscow, 4(2):187-194, Feb. 1959. DLC-The

results of investigations on the fading of 3 cm band signals reflected from standard reflectors with surface propagation in the zone of direct visibility are given.

A result of the investigation is a preliminary estimate of the effect of the surface on the formation of reflected radio signal amplitude fluctuations. The result of

the work may be useful for passive retranslation, as well as in radiolocation of

ground level targets. --Authors' abstract.

Semenov, A. A. and Karpeev, G. A. , O sviazi chastoty zamiranil amplitudy polia

UKV so skorost'iu drefta neodnorodnostei v troposfere i chastotoi nesushche'l'. (Relationship between the fading frequency of the ultrashortwave field amplitude

and the drift velocity of tropospheric inhomogeneities and the carrier frequency.

Moscow. Universitet, Vestnik, Seriia Matematiki, Mekhaniki, Astronomii,

Fiziki, Khimii, No. 6:131-136, 1959. 5 figs. , 7 refs. (Unchecked) -In their

evaluation of the effect of regular drift of the medium and chaotic movement of

irregularities, the authors investigate the space-time correlation function of the

complex field amplitude in two points. A moving coordinate system is introduced

and an equation is derived for the field amplitude. It is found that field fluctuations are determined by characteristics of receiving and transmitting equipment as

well as by permittivity fluctuations and velocity of the drift of irregularities.

Some experimental data are compared with theoretical data. The fading rate in- creases with an increase in carrier frequency but the authors find it impossible

to confirm a linear dependence. --R. M.
166

E-671 Siforov, V.I. , Aleksandr Stepanovich Popov i razvitie radioelektroniki. (Aleksandr Stepanovich Popov and the development of radioelectronics. ) Radiotekhnika,

Moscow, 14(3):3-8, March 1959. Transl. into English in Radio Engineering, N. Y. , 14(3): 1-12, 1959. DLC--Brief historical account of Popov's contributions to radio

and electronics followed by a series of short statements about each of the various

electronic fields ranging from propagation theory, electronic computers, and in- strumentations to scattering and antennas. Points out achievements, trends,

plans for future development and the author's views pertaining to current deficiencies in several fields. --R.M.

E-672 Staras, H. and Wheelon, A. D. , Theoretical research on tropospheric scatter propagation in the United States. 1954-1957. IRE Transactions on Antennas and Propagation, N. Y. , 7(l):80-87, Jan. 1959. 2 figs. , table, 38 refs. , 25 eqs. DLC--

Recent progress in the theory of tropospheric scatter propagation in the U.S. is

outlined. In the past 3 yrs, the emphasis of theoretical research has shifted from

the analysis of the average signal level to the analysis of the signal statistics and

to the underlying hydrodynamics of atmospheric turbulence. As might be expected

in such a new and complete field, there is far from unanimity of opinion as to the

best model to explain the myriad experimental results. --Authors' abstract.

E-673 Stiles, K.P. , Tropospheric scatter path loss tests Florida - Bahamas. IRE Transactions on Communications Systems, N. Y. , 7(3):205-208, Sept. 1959. 8 figs.

DLC (TK5101. 122) -Telephone service between the U.S. and the Bahama Islands

is now provided by means of high frequency radio systems working in the 2-7 Mc

range. To handle properly the large volume of traffic during the peak winter sea- son requires that more than present nine circuits be provided. The lack of available frequencies in the 2-7 Mc range, together with the comparatively poorer grade

of facility obtained from these radio systems, makes it desirable to investigate

other methods of providing telephone facilities. The fact that the present MiamiHavana tropospheric scatter system is performing so well, and that the distance

from Miami to Nassau is the same as that to the Cuban terminal, made this type

of system very attractive. At the time the Cuban system was being developed,

klystron tubes capable of high outputs above 1000 Mc, were not available. For

this reason, the Cuban system was designed to operate in the 700-900 Mc range.

Since that time tubes capable of high output levels at frequencies above 2000 Mc

have been developed, and it was considered desirable to operate at these higher

frequencies rather than in the lower part of the UHF spectrum. Path loss tests were made over a 9 week period on the Florida-Nassau path using a frequency of

1970 Mc. These tests are discussed and some comparisons are drawn between

them and the path loss tests made to Cuba at 800 Mc two years earlier. The

Nassau tests indicated that a satisfactory 60 channel radio system could be provided through use of 10 kw transmitters and 30 ft parabolic antennas. --Author's

abstract.

E-674 Svien, Arlon S. and Domingue, Jules C. , Tropospheric scatter propagation characteristics. IRE National Convention Record, Pt. 1:3-9, 1959. 8 figs. , table,

3 refs. DBS --Two parameters of tropospheric propagation, the effects of elevated

horizons and antenna height, are discussed on the basis of 2& yrs of detailed

measurements conducted at the U.S. Army Electronic Proving Ground in Arizona

and New Mexico, over paths varying between 50 and 385 mi, at frequencies of

810, 380 and 950 Mc. Agreement between experimental values and those obtained from literature is found to be excellent. --G. T.
167

Tao, Kazuhiko and Sawaji, Kazuaki, On the graphical method of calculation of

field strength for effective Earth radii other than 4/3 times the actual radius and

for any antenna heights and freguencies . Japan. Radio Research Laboratories,

Tokyo, Journal, 6(25):311-329, April 1959. 3 tables, eqs. DBS. Japanese ver- sion with English summary in its Review, 5(19):93-144, April 1959. 7 figs. , 4

tables, 3 refs. , eqs. DLC--In resolution No. 21, the VIII Plenary Assembly of

the C. C. I. R. requested the Director of the C.C.I. R. to prepare a supplement to the C.C.I. R.Atlas (1955) by using a suitable mathematical transformation for the

calculation of field strength for the effective Earth radii other than 4/3 times the

actual radii and for other values of earth's conductivity. Resolution No. 22 also

provided to find a method of interpolation for antenna heights and frequencies

different from those contained in the Atlas. Concerning the above mentioned

corrections, the method of calculating field strength in the diffraction region has

been proposed by the C. C. I. R. Secretariat. Though the method of the C.C.I. R.

is very useful, yet the calculation is fairly complicated and needs much time for complete processing. A much simpler graphical method has been obtained which

enables to measure the required field strength in a few minutes. Moreover,

another method to find out the position of interference patterns in an optical

region is given. (Met. Abs. 14. 5-144) --Authors' abstract.

Tatarskii, Valerian Il'ich, Teoriia fluktuatsionnykh iavlenii pri rasprostranenii

voln v turbulentnoY atmosfere . (Theory of fluctuation phenomena associated with

the propagation of waves in a turbulent atmosphere.) Moscow, Akademiia Nauk

SSSR, 1959. 230 p. 45 figs. , 99 refs. , numerous eqs. DLC (QC931. T3)--A

unique and useful textbook or monograph presenting the basic theory of statistical

turbulence and its application to the solution of problems concerning propagation

of radio, light and sound waves in a turbulent atmosphere. Methods of observing

or recording turbulent fluctuations of temperature, wind, and of computing the

data, the nature or microstructure of turbulent flow, the scattering of electromagnetic waves in a turbulent atmosphere and of sound waves in local isotropic tur- bulence, solution of amplitude and phase fluctuation problems for monochromatic

waves on the basis of geometric optics and on the basis of wave equation and of

spherical waves and finally, experimental data for the lower troposphere for radio

and light waves and scintillation data for stars and telescopes. (Met. Abs.

11.11-13)-M.R.

Thompson, M.C.Jr. and Janes, H.B. , Measurements of phase stability over a low level tropospheric path. U.S. National Bureau of Standards, Journal of Research, Sec. D, 63(1):45-51, July/Aug. 1959. 9 figs. , 5 eqs. DLC, DWB--

A knowledge of the statistics of atmosphere induced variations in the phase of

the received signal (i. e. , variations in electrical path length) is essential in

evaluating the reliability of any system using radio waves for measuring distance

and/or velocity. This paper describes an analysis of phase variations measured

at 9400 megacycles per second over a 9. 4 mi path near Boulder, Colo. , during a 40 hr period in Sept. 1958. This power spectral density of these variations is

shown to be approximately proportional to f~2. 8 OVer a wide range of frequencies

throughout the period of recording. The long term phase variations are closely

correlated with atmospheric refractivity measurements made at the path terminals.

(Met. Abs. 12. 3-98) -Authors' abstract.
168

E-678 Tomlinson, H.T. (Chance-Vought Aircraft Corp. , Arlington, Tex. ) and Straiton,

A. W. (Univ. of Texas, Austin), Analysis of 3 cm radio height gain curves taken

over rough terrain. IRE Transactions on Antennas and Propagation, 7(4):405-413,

Oct. 1959. 27 figs. (incl. photos), table, 3 refs. , 4 eqs. DLC --This report describes the effect of terrain and meteorological conditions on the height gain pat- tern of 3. 2 cm radio waves over various short transmission paths. Equivalent re- flection coefficients are obtained and potential reflection areas are investigated.

A study of time variations in the height of nulls in the signal strength pattern is

made and the relationship between movement of the nulls and the corresponding

refractive index distribution is considered. (Met. Abs. 12. 8-392) --Authors'

abstract.

E-679 Venkateswarlu, P. and Satyanarayana, R. (both, Physics Dept. S.V.Univ. , Tirupati) , Propagation of around waves across a land/sea boundary. Current

Science, Bangalore, 28(6):239, June 1959. Table, 3 refs. DWB, DLC-Observations on the field strength of ground waves of 447. 9 m wave length from A.I. R.

Calcutta station suggest that a recovery of field strength as expected from MILLINGTON's analysis (1949) is possible even at these wave lengths. Relative

intensities determined theoretically and experimentally at widely separated sta- tions in India are tabulated. The details regarding the extent of recovery and the

field strength expected at Tirupati on the basis of NUKKUBGTIB's theory are being

worked out. (Met. Abs. 12. 10-137) --E. Z. S.

E-680 Vogelman, J. H. ; Ryerson, J. L. and Bickelhaupt, M.H. , Tropospheric scatter

system using angle diversity. Institute of Radio Engineers, N. Y. , Proceedings,

47(5):688-696, May 1959. 18 figs. , 7 refs. DLC--This paper proposes an extension of the angle diversity technique as a means toward solution of several problems restricting use of over the horizon microwave communications. The paper

suggests application of a microwave multibeam system as an attack on the problems of transmitter tube limitations, "medium to aperture" coupling loss, and

VHF band interference. A simple experiment is described and results evaluated.

The experiment provides a measure of verification of previous theoretical work on which the proposed technique is based. Results of numerous path calculations

are included to provide the reader with an estimate of improvement to be gained

by the use of this expansion of the angle diversity technique over a continental

system. —Authors' abstract.

E-681 Weisbrod, S. and Anderson, L. J. , Simple methods for computing tropospheric

and ionospheric refraction effects on radio waves . Institute of Radio Engineers,

N. Y. , Proceedings, 47(10): 1770-1777, Oct. 1959. 7 figs. , 7 refs. , 51 eqs.

DLC—The paper describes a simple and accurate method for computing ionospheric

and tropospheric bending. The only assumptions made are that the refractive

gradient is radial and that the refractive index profile can be approximated by a

finite number of linear segments whose thickness is small compared with the

earth's radius. These assumptions are readily justifiable in all practical cases. Since there are no limitations on the angle of elevation and the shape of the re- fractive index profile, the method has a wide application and it is extended to cover other refractive effects such as retardation, Doppler error and Faraday

Rotation. --Authors' abstract.
169

E-682 Wheelon, A. D. , Radio scattering by tropospheric irregularities. Journal of Atmospheric and Terrestrial Physics, N. Y. , 15(3/4): 185-205, Oct. 1959. 5 figs. , table, bibliog. p. 203-204, numerous eqs. DLC--The existence of time varying

irregularities in the tropospheric index of refraction has been firmly established

by numerous measurements with microwave refractometers. The physical reality

of these apparently random fluctuations poses an important problem for turbulence

theory in itself. The effects of such irregularities in scattering radio waves both

within and beyond the horizon has raised a much broader and more vital class of

questions. The combination of turbulence theory and electromagnetic propagation

theory has been used to explain the propagation of microwaves beyond the horizon.

The important role of refractive fluctuations is suggested by the fading and band

width limitations of scatter signals. Scintillation of the amplitude and phase of

electromagnetic waves propagated through a region of refractive irregularities is

discussed with the same techniques. --Author's abstract.

E-683 Zhevankin, S.A.and Troitskii, V.N. , Absorption of centimeter waves in the at- mosphere . Radio Engineering and Electronics, N. Y. , 4(1):30-41, 1959. Fig.,

2 tables, 6 refs. , 36 eqs. Transl. from Russian in Radiotekhnika i Electronika,

Moscow, 4(l):21-27, Jan. 1959. DLC--In this article general expressions are derived for the absorption of a wave propagated in the atmosphere. A "moist"

atmosphere is taken as representative of the atmosphere with certain parameters

which vary exponentially with the altitude. --Authors' abstract.

1960

E-684 Abbott, Richard L. , Bibliography of tropospheric radio wave scattering. U.S.

National Bureau of Standards, Technical Note No. 80, Nov. 1960. 79 p. 681

titles. DWB (M(055) U585te) -Except for 65 references to literature prior to 1950,

the 681 unannotated entries cover the period 1950-1960. The bibliography is ar- ranged alphabetically by author, in chronological order. It is provided with an

author index, and a subject index with brief subdivisions under the classifications

1) theoretical, and 2) experimental. (Met. Abs. 14. 6-9D--W. N.

E-685 Akima, Hiroshi, Experimental test of reciprocal radio wave propagation over a VHF circuit . Japan. Radio Research Laboratories, Journal, 7(30): 125-128, March

1960. 2 figs. , 3 refs. DBS—From an experimental test of reciprocal radio wave

propagation over a circuit of the frequency 152. 05 Mc/s and a path about 125 km

long,- no phenomena could be found that would deny the reciprocity of propagation.

--Author's abstract.

E-686 Akima, Hiroshi et al. , Experiment in the intermittent communication of the VHF

teletype channel. Japan. Radio Research Laboratories, Journal, 7(34): 637-641,

Nov. 1960. Fig. , 3 tables. DBS--A simple experimental investigation of the in- termittent communication is made on a VHF radio teletype channel. Frequency

shift (FS) modulated teletype signals are intermitted by the control signal from

the receiving station. This control signal is of on-off carrier, which is modulated

by the signal (plus noise) level of the receiving station which is higher or lower

than the limited level. The results of the test show that the character error rate

of the intermittent communication is 0. 0073% and that of the continuous method

is 0. 14%. These errors occur in case of interference of various kinds, but considering the errors due to signal fade-out alone, the character error rate is

0. 0021% for the intermittent communication and it is 0. 11% for the continuous

communication. The mean transmission loss of the intermittent communication

is about 7%. --Authors' abstract.
170

E-687 Ames, L.A. ; Martin, E. J. and Rogers, T. F. (all, AF Cambridge Res. Center,

Bedford, Mass.), Airborne measurement of 1. 36 m fields to ranges in excess of

900 miles and at altitudes from the surface to 40, 000 ft. (In: Desirant, M. and

Michiels, J.L. (eds.), Electromagnetic wave propagation. London, Academic

Press, 1960. p. 215-226. 14 figs. ) CU-S (QC661. D458) --The decay of tropospheric fields well beyond the radio horizon at 1. 36 m is a monotonically decreasing function of distance out to about 800 statute miles. The "effective" distance

concept was shown to be accurate and useful for calculating path losses over a smooth Earth in the distance region of 100-600 mi. Large height gains were predicted in the tropospheric scatter field which decrease with increasing distance.

It was found that scatter fields exist above the tropopause and their magnitude

and characteristics did not differ to any great extent from predictions. The ionosphere persistently manifests its influence at a wavelength much shorter than has

heretofore been demonstrated to exhibit characteristics of continuous ionospheric

propagation. --Authors' abstract and E. Z. S.

E-688 Anderson, W.L.; Beyers, N. J. and Rainey, R.J. , Comparison of experimental

with computed tropospheric refraction. IRE Transactions on Antennas and Propagation, N. Y. , 8(5):456-461, Sept. 1960. 4 figs. , 3 tables, 4 refs. DLC--Limits

of applicability of ray tracing in computing tropospheric refraction at White Sands

Missile Range have been further explored. 286 comparisons were made, all for a path from radar to fixed beacon of about 45 mi and an elevation angle of 17. 99

milliradians. A horizontally stratified atmosphere was assumed. Refractive

index profiles were prepared from a variety of weather data, and classified A,B,

or R, in descending order of reliability prior to ray tracing calculations. Angle

observations were made with an FPS-16 C-band radar having a quoted instrumental

accuracy of 0. 14 milliradian rms. Angle readings varied from 18. 36 to 20. 54 milliradians, with mean of 19. 01 milliradians and standard deviation of 0.41 milliradians. The rms deviation of computed from experimental angles ranges from 0. 28

to 0. 41 milliradian for different classes of data. The ratio of this deviation to the

deviation from over all mean varies from 0. 68 for Class A to 1. 00 for Class R.

Thus the improvement over a standard atmosphere varies from 32% to 0, and cor- relates directly with quality of weather information. For this experiment it is con- cluded that most of the rms elevation angle error is contributed by atmospheric

conditions. Although ray tracing methods provide a significant correction when

sufficiently good weather information is available, there still remains a large un- certainty not accounted for by equipment. --Authors' abstract.

E-689 Andrieux, G. ; Cayzac, J. and Ducot, C. , Equipment hertzien telephonigue pour

propagation par diffusion tropospherigue . (Tropospheric diffusion radio link equipment. ) L'Onde Electrique, Paris, 40(394): 74-81, Jan. 1960. 10 figs. DLC-The

authors describe an experimental 30 channel equipment using tropospheric diffusion transmission. The transmitter operates at 900 Mc/s and radiates a power of

1.5 kW. It incorporates a 3 cavity klystron amplifier which has been developed

by the Laboratoires d'Electronique et de Physique. The gain of this amplifier is

35 db for a bandwidth of 2 Mc/s. The carrier wave is frequency modulated in a 3 tripler stage phase corrected modulator. The receivers use the EC 56/57 tube as UHF pre-amplifier; the noise factor so obtained is less than 8 db. Double space

diversity with a low frequency weighting is employed. The experimental results

obtained on the Paris-Caen (204 km distance diffusion angle 1. 5°) are given. With

an aerial of 5 m diameter, the median fluctuation noise in the most unfavorable

channel, in a pure frequency modulation system was —46 db as measured on a psophotometer. Inter-modulation noise with normal loading of the system was in

the region of — 53 db. It is possible to deduce the performance of the equipment

with larger aerials, with pre-emphasis, etc. (Met. Abs. 15. 1-99) --Authors' abstract.
171

E-690 Asai, Jun-ichi; Fujikawa, Masatoshi; Tsuchiya, Kiyoma; Ishii, Takahiroo and

Kajikawa, Makoto, Statistical results of VHF propagation over the sea on the

path beyond the horizon. Japan. Radio Research Laboratories, Tokyo, Review,

6(26):261-267, Sept. 1960. 12 figs. , 5 tables, 4 refs. In Japanese; English

summary p. 261. DLC--This paper gives some statistical results of VHF propagation tests which were made on the path beyond the horizon, about 77 km, over

the Kashima Nada. During the tests simultaneous transmissions on 60 Mc/s and

150 Mc/s were measured for the whole year from Dec. 1957 to Nov. 1958. Three

statistics were used such as, the relative field intensity, fading range, and fading rate for an hour, in order to describe the character of propagation. There was

a marked seasonal variation of the field intensity. On 60 Mc/s the monthly mean

values of hourly medians registered the maximum value 15. 5 db in Dec. and the

minimum 8. 4 db in July. On 150 Mc/s, the maximum value was 18 db in Sept.

and the minimum 10. 1 db in March. There was generally little diurnal variation.

For a seasonal variation of the fading range for an hour, there was a marked similarity on 60 Mcs and 150 Mc/s. The maximum value of monthly mean values was

6. 6 db in July and the minimum was 1. 7 db in Feb. on 60 Mc/s, and the maximum

was 7. 2 db in Sept. and the minimum 1. 3 db in Feb. on 150 Mc/s. There was a similar seasonal variation of the fading rate for an hour on both frequencies. The

maximum value of monthly mean values was 46 fades/hr in March and the minimum 12 fades/hr in June on 60 Mc/s, and the maximum was 47 fades/hr in Oct.

and the minimum 11 fades/hr in June. The diurnal variation of the fading rate was in general greater in the daytime and less at night. (Met. Abs. 14.4-121)

--Authors' abstract.

E-691 Bass, F. G. , Granichnye usloviia dlia elektromagnitnogo polia na poverkhnosti

s proizvol'nym znacheniem dielektrichesko¥ pronitsaemosti. (Boundary conditions

for the electromagnetic field at a surface with arbitrary dielectric constant.

)

Radiotekhnika i Elektronika, Moscow, 5(3):389-392, March 1960. 2 refs. , 11

eqs. Transl. into English in Radio Engineering and Electronics, N. Y. , 5(3):49-53,

1960. --Boundary conditions are derived for the electromagnetic field at a surface

with arbitrary dielectric constant. In the general case these conditions are nonlocal. Cases where passage to local boundary conditions is possible are considered. --Author's abstract.

E-692 Bayot, R. and Forest, A., Un equipment pour faisceaux hertziens transhorizon

dans la bande des 170 MHz. (A transhorizon radio link system in the 170 Mc/s

band.) Onde Electrique, Paris, 40(394) :65-73, Jan. 1960. 15 figs. DLC»The

design and performance characteristics of a tropospheric scatter system for a maximum of 36 telephone channels are described, and block diagrams of its components are given. The system uses a phase modulator with de-emphasis, has a transmitting power of 1 kw, obtained by a single output tube, and two receivers

with double diversity resulting from combining carrier frequencies. ---R.M.

E-693 Bean, Bradford R. (NBS, Boulder, Colo.), Atmospheric bending of radio waves.

(In: Desirant, M. and Michiels, J. L. (eds.), Electromagnetic wave propagation.

London, Academic Press, 1960. p. 163-181. 10 figs. , 3 tables, 12 refs. , 10 eqs.

CU-S (QC661. D458) --Presents several models of the height distribution of atmospheric refractive index that should be of use in radio propagation problems. Considering the average refractive index structure of the atmosphere and results of

recent statistical studies of radio ray bending, it was found that these models may

be expressed in terms of the value of the refractive index at the Earth's surface.

--E.Z.S.
172

E-694 Bean, B. R. ; Cahoon, B. A. and Thayer, G. D. , Tables for the statistical prediction of radio ray bending and elevation angle error using surface values of the re- fractive index. U.S. National Bureau of Standards, Technical Note, No. 44, March

16, 1960. p. 3+ , Fig., 3 tables, 3 refs. DLC --Radio ray bending, r . and elevation angle error, £ , have been calculated for a wide range of meteorological

conditions at 13 climatically diverse U.S. radiosonde stations. The parameters in

the observed linear regression equations of T and t upon the surface value of the

refractive index are given for heights of 0. 1 to 70 km and initial elevation angles

of the ray from to 900 milliradians. --Authors' abstract.

E-695 Bean, B. R.and Dutton, E. J. , On the calculation of the departures of radio wave

bending from normal. U.S. National Bureau of Standards Journal of Research, Sec.

D, 64(3): 259-263, May/June 1960. 3 figs. , 3 tables, 22 refs. , 14 eqs. DWB,

DLC --The calculation of non-normal tropospheric bending of radio waves is treated

in terms of a reduced-to-sea level value of the refractive index. This method emphasizes departures of bending from the average bending for the U.S. and consists

of visualizing ray bending as consisting of two parts; an "average" component

and a "departure from average" component. The "average" component comprises

most of the bending and is obtained accurately from refraction tabulations while

the component due to departures is easily obtained by graphical means. (Met.

Abs. 14. 4-127) -Authors' abstract.

E-696 Bean, B. R. ; Horn, J. D. and Ozanich, A. M.,Jr. , Climatic charts and data of

the radio refractive index for the U.S. and the World. U.S. National Bureau of

Standards, Monograph No. 22, 1960. 178 p. 117 figs. , 11 tables, 18 refs. DLC

(QC100. U556)--The radio refractive index of air, n = 1 + N10'6 , is a function of

atmospheric pressure, temperature, and humidity and varies in a systematic fashion with climate. Included in this paper is a compilation of refractive index data.

Data listings made up of observations from 45 U.S. surface weather stations for 2 hr intervals over an 8 yr period are given. Mean values, maxima, minima and

standard deviations of the refractive index have been calculated and tabulated for

these observations. Additionally, mean vertical profiles of the refractive index

have been prepared for 43 U. S. upper air sounding stations from long term means

of pressure, temperature, and humidity. Earlier studies of refractive index climate are assimilated and put into perspective. One such study is an extensive

analysis and mapping of the refractive index climate of the U.S. A worldwide

radio refractive index climatology is developed, based upon monthly mean observations of pressure, temperature, and humidity. An important finding of these

climatological investigations is the strong correlation of N with height. A re- duced-to-sea-level value of the index, termed N , is used to eliminate this sys- tematic height dependence. The surface value of N, Ns , may be estimated 4-5

times more accurately from charts of N than from similar sized charts of Ns it- self. From climatic charts of N , Ns may be estimated at any given location in

the U.S. throughout the day during every season. In addition, detailed annual

and diurnal cycles, as well as 8 yr cumulative probability distributions, are given for 12 representative U.S. stations. On a worldwide basis, charts of mean

No are presented for both summer and winter seasons. (Met. Abs. 14. 6-21)

--Authors' abstract.

E-697 Bean, B. R. ; Horn, J. D. and Riggs, L.P. (all, Nat'l. Bur. of Standards, Boulder,

Colo.), Refraction of radio waves at low angles within various air masses.

Journal of Geophysical Research, Wash. , D.C. , 65(4): 1183-1187, April 1960.

5 figs. , table, 23 refs. , 5 eqs. DLC --The refractive index structure and bending of radio ways within air masses of nonexponential refractive index height
173

structure is treated in terms of the value expected in an average atmosphere of

exponential form. It is demonstrated that refraction differences within air masses

arise from departures of refractive index structure from the normal exponential de- crease with height. The effect upon radio ray refraction of these departures from

the normal exponential refractive index structure is most pronounced for small

initial elevation angles of the radio ray. (Met. Abs. 12. 10— 131) --Authors' abstract.

E-698 Bean, B. R. ; Thayer, G. D. and Cahoon, B. A. , Methods of predicting the atmospheric bending of radio rays. U.S. National Bureau of Standards, Journal of Research, Sec. D, 64(5):487-492, Sept. /Oct. 1960. 5 figs. , 14 refs. , 11 eqs.

DWB, DLC--Three methods for predicting the bending of radio rays when the refractive index profile above the surface layer is unknown have been developed recently by the authors. These methods are a statistical technique for refraction at high

initial elevation angles, estimation of bending from an exponential model of atmospheric refractive index, and a modification of the exponential model to account for the heavily weighted effects of anomalous initial refractive index gradients at small initial elevation angles. Each model is dependent upon the value of the re- fractive index at ground level, or in the case of superrefraction, the additional

knowledge of the refractive index gradient next to the earth's surface. Each

method works best in a particular range of initial elevation angles or meteorological conditions. The height and angular ranges of application of each method are checked by comparison with values obtained from 77 diverse refractive index profiles representative of wide climatic variation. It is found that the use of the

best of the three methods will always result in a prediction of the total atmospheric bending within 10% for initial elevation angles from zero to 10 milliradians

and to within 4% for initial elevation angles greater than 17 milliradians ( 1 def).

(Met. Abs. 12. 10-132) -Authors' abstract.

E-699 Beckmann, Petr (Czechoslovakia Academy of Sciences, Prague), Generalized

Rayleigh distribution and its application to tropospheric propagation. (In: Desirant, M. and Michiels, J. L.(eds.), Electromagnetic wave propagation. London,

Academic Press, 1960. p. 445-449. Fig., table, 6 refs. , 8 eqs. ) CU-S (QC661.

D458) --Derives the probability distribution of the amplitude of the vector sum of n random unit vectors with given (not necessarily uniform) phase distribution,

which includes the Rayleigh distribution as a special case, and compares the re- sult with experimentally measured distribution of the rapid fading in transhorizon

tropospheric propagation. --E. Z. S.

E-700 Beckmann, P. , Die Einrichtung einer 1. 3 GHz Strecke zwischen Prag und Kolberg

bei Berlin. (Installation of a 1. 3 kMc link between Prague and Kolberg bei Berlin.)

Radio und Fernsehen, 9(3):71-73, Feb. 1960. 3 figs. , ref. DLC -The authors first consider the basic principles and problems of long distance propagation of radio waves. Two explanations of field intensity are set out: on the one hand, the scatter concept, particularly current in the U.S. , and on the other hand, that of partial

reflections in the area of deviating refraction characteristics. Both explanations

are based on tropospheric irregularities. The median value of the signal far beyond the optical horizon is relatively constant. Seasonal and weather conditions as well as very short amplitude fluctuations due to movement in the troposphere

modify the signal. Antenna-to-medium coupling loss is explained. Space and

frequency diversity are found to increase link stability and to considerably reduce

short period signal fluctuations. Measurements and practical operations of scatter links are described. There are three 1. 1 - 1. 2 kMc links in East Germany:

Dresden - Kolberg (125 km); Fichtelberg - Kolberg (208 km); and Inselberg -
174

Kolberg (280 km); and a 1. 3 kMc link between Prague and Kolberg operated jointly

by the Institute of Radio Engineering and Electronics in Prague and the Industrial

Laboratory of Radio and Television in Kolberg. The equipment, measurements and

operational factors on the latter link are described and field strength records are given. A profile map of the link is also shown. The link is expected to continue

daily operations for two years.

E-701 Bellman, Richard and Kalaba, Robert (both, Rand Corp. .Santa Monica, Calif. ), Invariant imbedding and wave propagation in stochastic media. (In: Desirant, M.

and Michiels, J.L. (eds.), Electromagnetic wave propagation. London, Academic

Press, 1960. p. 243-252. 4 figs. , 27 refs. , 30eqs.) CU-S (QC661. D458)--

Describes an application of the theory of invariant imbedding to the propagation

of electromagnetic waves through an inhomogeneous medium, especially where the

inhomogeneity is stochastic in origin. Problems of this sort arise in a variety of

fields including radio wave propagation and acoustics. --Authors' abstract and

E. Z.S.

o E-702 Blomquist, Ake (Res. Inst, of Nat'l. Defence Stockholm), Local ground wave field

strength variations in the frequency range 30-1000 MHz. (In: Desirant, M. and

Michiels, J.L. (eds.), Electromagnetic wave propagation. London, Academic

Press, 1960. p. 127-142. 12 figs. , ref. , 8 eqs. ) CU-S (QC661. D458) -Results

from a number of field strength recordings of the ground wave are presented. Measurements were made over different types of terrain in middle Sweden and at different seasons both at vertical and horizontal polarization. Local field strength var- iations due to vegetation and ground moisture conditions with low antennas are discussed and field strength distribution curves are given. --Author's abstract and

E.Z.S.

E-703 Boithias, L. and du Castel, F. , Etude d'un faisceau hertzien transhorizon en

Afrique Qccidentale. (Study of an over the horizon radio beam in West Africa.

)

L'Onde Electrique, Paris, 40(394): 39-45, Jan. 1960. 15 figs. , 9 refs. French

and English summaries. DLC --Propagation tests at 100 and 430 Mc/s have been

carried out by the Centre National d'Etudes des Telecommunications between

Dakar and Conakry from Nov. 1957 to April 1958. The systems studied were 270,

280 and 170 km in length. The results obtained were examined from the point of

view of the variation in the mean loss. An important diurnal effect was noted.

A correlation between the monthly variations in propagation loss and a parameter

and the climatic conditions of the region concerned, is attempted. The study included the variations of 3 parameters, the refractive index at ground, the mean

gradient index defined by the values of the index at the surface and at the alti- tude of 1000 m, the stability of the lower atmospheric layers and the vapor ten- sion at the surface. The annual variations of radio meteorological parameters

are very different and therefore it is difficult to select the most favorable season

for propagation. It seems that in tropical regions the radio meteorological parameters comply with more complex laws than in temperate climates. The index

gradient is probably the most suitable parameter. Therefore, it is concluded

that from Dec. to Feb. would be the worst period. The variations of signal

strength are then examined. The analysis of the amplitude yields information on

the characteristic laws, while the analysis of duration provides other interesting information. The results are used to design an over the horizon project between

Dakar and Conakry. Some general inferences are drawn on the influence of a tropi- cal region of UHF over the horizon propagation. (Met. Abs. 12. 1-99) -A V

and Authors' abstract.
175

E-704 Bolgiano, Ralph, Jr. (Cornell Univ. ), A theory of wavelength dependence in ultrahigh frequency transhorizon propagation based on meteorological considerations.

U.S. National Bureau of Standards, Journal of Research, Sec. D, 64(3): 231-237,

May/June 1960. 6 figs. , table, 24 refs. , 13 eqs. DWB, DLC--Recent radio data

indicate that the wave length dependence of ultrahigh frequency transhorizon propagation varies widely in time. This is in contradiction with theoretical explanations

previously set forth. Each attempt to account for the underlying effects of ever- present atmospheric motions has, in the past, pointed toward a unique form of the

dependence. Extensive discussions have resulted as to the validity and relative

merits of the various forms, but at no time has a variable wavelength dependence

been proposed. Since scatter propagation theory has predicted so satisfactorily

the broad aspects of the radio signals, it is retained as the basis for further analysis. A new model is developed for the structure of refractive index fluctuations

induced by turbulence. Grounded on a theory of homogeneous turbulence in a stably stratified atmosphere, which has been developed concurrently by the author,

this new model provides an explanation for the observed distribution of wavelength

dependence. It suggests that at times when the dynamic stability of the air within

the scattering volume is neutral, the received power should be nearly independent

of radio wavelength. On the other hand, when the atmosphere is dynamically

stable the signal strength should be proportional to the square, or higher power, of

the wavelength. These predictions have been tested by comparing the results of a scaled frequency experiment with simultaneous meteorological data gathered along

the path. Richardson's number for the 1 to 3 kilometer layer, within which the

principal scattering volume lies, has been employed as an index of dynamic stability, though it falls short of ideal in some respects. The 0. 8 value of correlation

found between Richardson's number and the wavelength dependence is highly suggestive that a relation of the nature predicted does, in fact, exist. (Met. Abs.

12. 10-133) -Author's abstract.

E-705 Bremmer, H. , On the theory of wave propagation through a concentrically stratified troposphere with a smooth profile. Pt. 1. Discussion of the extended W. K. B. approximation. U. S. National Bureau of Standards, Journal of Research, Sec. D,

64(5): 467-482, Sept. /Oct. 1960. Fig., 13 refs. , 64 eqs. DLC, DBS--The W.K.R

approximation for the solution of the height gain differential equation for a curved

stratified troposphere is discussed in detail. (For Pt. 2, see E-892). The approximation depends mainly on a variable u ^ (r) which can be interpreted as the height

dependent contribution of the phase for a field solution obtained by separation of

variables. An expansion of u ^ (r) with the aid of partial integrations leads to further approximations which facilitate the determination of the eigenvalues, and

of the amplitudes of the modes connected with the propagation problem. The in- fluence of the refractive index profile, if assumed as smooth, then appears to be

restricted to a dependence on the surface values of .this index and of its gradient

insofar as propagation over ground is concerned. Further, all height effects of

elevated antennas can be expressed in terms of the distance to the corresponding

radio horizon. This results in simple relations between the fields connected with

two different refractive index profiles, provided both profiles coincide near the

earth's surface. (Met. Abs. 14. 7-110) --Author's abstract.

E-706 Broussaud, G. and Malnar, L. , Prototype de transmission multiplex par diffusion

tropospherique. (A prototype of multiple tropospheric scatter propagation.

)

L'Onde Electrique, Paris, 40(394): 83-95, Jan. 1960. 24 figs. , foot-refs. , eqs.

DLC -The development of a prototype 2000 Mc/s over the horizon radio link equipment is described. The principal characteristics of the equipment are: power 10

kW, 12 m diameter parabolic reflectors, frequency diversity, 36 telephone channels, frequency modulation. After considering the general criteria which determined the choice of characteristics, the most important features of the develop-
176

ment are examined and in particular certain interesting wave guide sections are described. (Met. Abs. 12. 1-98) --Authors' abstract.

E-707 Bugnolo, Dimitri S. (Dept. of Elec. Engr. , Columbia Univ. ), On the question of

multiple scattering in the troposphere. Journal of Geophysical Research, Wash. , D.C., 65(3): 379-884, March 1960. 2 figs. , 17 refs. , 3 eqs. DLC -A criterion

is developed to serve as a measure of multiple scattering in the troposphere as a

result of dielectric noise. The question to be answered is: What is the probability that any ray of the incident field will be scattered at least twice in a distance

R? This useful criterion can serve as a measure of reliability for the usual single

scatter approximations. It is developed in detail for an arbitrary dielectric noise

and is applied to a number of special cases. The results indicate that multiple

scattering effects should be of importance in the microwave spectrum. (Met. Abs.

12. 3-99) --Author's abstract.

E-708 Bull, Gunther and Lange, Heinz, Fernausbreitunq der Ultrakurzwellen. (Long distance propagation of ultrashort waves.) Radio und Fernsehen, 9(3):67-70, Feb.

1960. 5 figs. , 3 refs. DLC--The authors examine possible mechanisms for the

propagation of ultrashort waves. These are: refraction in an inhomogeneous at- mosphere; bending on the curved surface of the earth or other obstacles; partial

reflection from layers and irregularities of the atmosphere; scattering in tropopause and propagation through the ionosphere due to scattering by inhomogeneities and meteor trails. Exceptional propagation conditions are also considered,

and are found to be due to the following: ground or elevated duct formation (rare

in temperate zones); partial reflection from tropospheric layers (predominant for

distances of 700-300 kilometers); occasional regular reflections from ionospheric

layers in the case of the longer meter waves; and scattering by meteor trails. --R.M.

E-709 Cabessa, R. , Les liaisons transhorizon. Conditions d'utilisation et performances

realisahles. (Operating conditions and performance of over the horizon links.)

L'Onde Electrique, Paris, 40(394) -.24-31, Jan. 1960. 12 figs. DLC--The UHF of over the horizon propagation through "tropospheric diffusion" is applied to actual

systems. For the radioelectric waves transmitted by the troposphere, conditions

of the free space propagation exist to a distance corresponding to the visible

horizon of the transmitting aerial. The diffraction zone begins beyond this distance wherein the attenuation depends on frequency and diffraction. The experimental results make it possible to compute the propagation loss. The daily, sea- sonal and sudden variations in propagation weakening are given. This technique

offers new possibilities of constructing telephone systems in insecure or inaccessible areas. The transmission characteristics of circuits are already meeting the

national requirements in spite of the difficulties of enormous attenuation between

transmitter and receiver. The relation of such performance has led to the development of special methods for the overall projects, i. e. , the choice of sites, the

conduct of propagation tests and the installation of telephone systems over hori- zon. Cost data and examples of the completed projects enable the future of these

links to be forecast. (Met. Abs. 15. 1-100) --A. V. and author's abstract.

E-710 Chernov, Lev Aleksandrovich (USSR, Acad, of Sciences), Wave propagation in a random medium. Transl. from the Russian by R.A.Silverman. N. Y. , McGraw-Hill,

1960. 168 p. 13 figs. , 61 refs. , 455 eqs. Price $7. 50. Review by Philip M.

Morse in Physics Today, 13(10):50, Dec. 1960. Transl. of Rasprostranenie Voln V

srede so sluchainymi neodnorodnostiam. (Propagation of waves in a medium with

random inhomogeneities. ) Moscow. Izd. vo Akademii Nauk, 1958. 158 p. --
177

This monograph contains a systematic treatment of the theory of wave propagation

in a medium with random inhomogeneities. In Pt. 1, the problem of wave propagation is studied using the ray approximation; Pt. 2, deals with the diffraction theory

of wave propagation; Pt. 3, discusses the question of how fluctuations in the incident wave affect the diffraction image formed by a focusing system. Some theoretical deductions are compared with experimental data. --E. K.

Clinger, A.H. and Straiton, A. W. (both, Univ. Texas), Adaptation of the radiosonde for direct measurement of radio refractive index. American Meteorological

Society, Bulletin, 41(5):250-252, May 1960. 2 figs. , 6 refs. . 2 eqs. DWB-This

paper describes a technique for converting a radiosonde for direct measurement of radio refractive index of air using standard meteorological sensors. Although

limited by the response time of the sensors, this device would provide for con- tinuous and direct measurement of refractive index to an accuracy satisfactory for

many radio applications. (Met. Abs. 12. 2-11) --Authors' abstract.

Denman, Eugene D. (Midwest Res. Inst. .Kansas City, Mo. ), A note on scatter

propagation. Institute of Radio Engineers, Proceedings, 48(1):112-113, Jan. 1960.

2 figs. , ref. , 14 eqs. DLC --Recent work in the field of scattering of electromagnetic energy from a periodic dielectric perturbation in the atmosphere shows an

interesting correlation to cover the horizon scattering from random turbulence.

This note describes and graphically illustrates the theoretical predictions for the

magnitude of the scattered electromagnetic energy from the periodic perturbation.

(Met. Abs. 13. 11-94) -I. S.

Dockes, J. and Koreicho, W. , Liaisons hertziennes transhorizon dans la qamme

4400 - 5000 MHz. (Over the horizon radio link systems in the 4400 - 5000 Mc/s

band.) L'Onde Electrique, Paris, 40(394): 100-105, Jan. 1960. 8 figs. , 5 refs.

French and English summaries. DLC --The article reviews the general information

available on tropospheric propagation in the neighborhood of 4500 Mc/s and establishes the basis for calculating the principal transmission characteristics of a given system. A general description is then given of equipment operating in the

4400 - 4500 Mc/s ranges. (Met. Abs. 12. 1-102) --Authors' abstract.

du Castel, Francois, Les faisceaux hertziens transhorizon. situation actuelle et avenir. (Over the horizon radio links, present and future position.) L'Onde

Electrique, Paris, 40(394) :9-18, Jan. 1960. 16 figs. , 14 refs. French and English summaries. DLC --The author first reviews the principal knowledge on over

the horizon transmission with ultrashort waves; the propagation loss observed

in a number of practical cases, the characteristics of fluctuations, theoretical

interpretation of the propagation phenomenon, and then he shows practical means

of approximately evaluating the loss of a given system. The considered cases

relate to transmissions over various distances from 300 up to 500 km. Figures

reproduce the linking characteristics and the damping distribution. The experimental results are likely to confirm the interpretation that the propagation is a phenomenon of partial reflection on the more or less stratified irregularities of

the atmosphere. The reflection of the incident radiation may have different val- ues owing to the variation of the reflective index with the nature of the atmospheric irregularities. The influences of climate and relief appear to play an important part in the propagation losses. The author then considers the basic fac- tors controlling the design of such an over the horizon radio link, and the method

of determining the quality for telephone and telegraphic transmission. Finally,

he discusses the performance which is obtained and is likely to be obtained with
178

present and future links for multiplex over the horizon systems. Satellites seem

to be the coming solution for transmission over very great distances as the reflected beams may prolong the over the horizon links. (Met. Abs. 12. 1-101) --A.V.

and author's abstract.

E-715 du Castel, F. , Reflexions partielles dans l'atmosphere et propagation a qrande

distance, VII. Note sur les phenomenes de propagation tropospherique. (Partial

reflections in the atmosphere and far reaching propagation, Pt. 7, Note on tropospheric propagation phenomena. ) Annales des Telecommunications, Paris, 15

(5/6): 137-142, May/June 1960. 9 figs. DLC--The author studies the reflection

phenomenon by introducing the reflective elements of the irregular surface of a tropospheric tilt. He gives evidence of the specular and diffused reflection pro- cesses as mentioned by A. SPIZZICHINO and J.VOGE and emphasizes the differ- ence of treatment of the problem by these two authors. Applying these results as well as the turbulent diffusion process to the phenomenon of tropospheric

propagation, he points out the various elements composing this complex phenomenon and establishes a comparison between them. (See refs. E-542, 328, 785,

786, and 772 for the other parts. ) (Met. Abs. 13. 4-10U--A. V.

E-716 du Castel, F. , Resultat experimentaux en propagation tropospherique transhori- zon . (Experimental results in transhorizon tropospheric propagation. ) Annales

des Telecommunications, Paris, 15(11/12) :225-259, Nov. /Dec. 1960. 6 figs. , 2 tables, 3 refs. DLC--Some results are given of the experimental studies made

in France on tropospheric propagation beyond the horizon, between 1957 and

1960. In the first part of this paper, a study and comparison are made of the

results obtained in various climatic regions, using frequencies of the order of

500 MHz, on paths of 150 to 400 km. These regions are located in Western

Europe, Western Mediterranean, the Sahara, West and Equatorial Africa. In the second part, an account is given of the characteristics of various propagation mechanisms based on the results obtained on some experimental links in

France. This study is concerned with the microscopic and macroscopic characteristics of the propagation and those of the troposphere, and brings out clearly

three fundamental mechanisms of propagation. The third part describes the re- sults obtained in an original experiment of the analysis of the rapid field variations in propagation beyond the horizon. (Met. Abs. 13. 4- 102) --Author's abstract.

E-717 Ducot, C. ; Andrieux, G. and Cayzac, J., Telecommunications utilisant la propagation tropospherique. (Telecommunications by means of tropospheric propagation. ) Acta Electronica, Paris, 4(1):97-114, Jan. 1960. 12 figs. , 13 refs.

DLC--With the comparatively recent discovery that wave propagation beyond the

horizon may result in fields much higher than the conventional diffraction theory

indicated, it has become possible to extend appreciably the range of UHF telecommunications, which were formerly restricted to line-of-sight paths. Important

studies have been devoted to the phenomena responsible for beyond-the-horizon

propagation by the troposphere. Data obtained from these studies are briefly

recalled. The requirements determining the development of the suitable equipment can be deduced from those data. The model of a 900 MHz equipment is

described. Intended for the transmission of a 30 telephon channel multiplex signal, it was set to operate in Nov. 1959 between Paris and Caen. The main re- sults of tests are given. Ways of improving the performances of tropospheric

transmission are considered, with particular emphasis on increasing range.

-R.M.
179

Felsen, L. B. and Siegel, K.M., Diffraction and scattering. U. S. National Bureau

of Standards, Journal of Research, Ser. D, 64(6): 707-714, 750, Nov. /Dec. 1960.

Foot-refs. , bibliog. p. 713-714, 750. DLC--This report is concerned with high fre- quency diffraction (involving obstacles with dimensions large compared to the

wavelength), Rayleigh scattering (obstacle dimensions small compared to the

wavelength) and scattering in the resonance region (obstacle dimensions comparable to the wavelength). Primary emphasis is placed on recent theoretical

developments, and selected pertinent experimental results are mentioned only

in conjunction with verification of certain theoretical predictions discussed in

the text. --From authors' abstract.

Fenton, Lawrence F. , The sum of log-normal probability distributions in scatter

transmission systems. IRE Transactions on Communications Systems, N. Y. , 8(l):57-67, March 1960. 16 figs. , 4 tables, 3 refs. , 39 eqs. DLC -The long

term fluctuation of transmission loss in scatter propagation systems has been

found to have a logarithmic normal distribution. In many important communication systems (e.g. , FM), the noise power of a radio jump, or hop, has lognormal statistical distribution. In a multihop system, the noise power of each

hop contributes to the total noise. The resulting noise of the system is therefore

the statistical sum of the individual noise distributions. In multihop scatter systems and others, such as multichannel speech transmission systems, the sum of

several log-normal distributions is needed. No exact solution to this problem is

known. The discussion presents an approximate solution which is satisfactory

in most practical cases. --Author's abstract.

Florman, E.F. and Plush, R. W. , Measured statistical characteristics and narrow band teletype message errors on a single sideband 600 mile long ultrahigh fre- quency tropospheric radio link. U.S. National Bureau of Standards, Journal of Research, Ser. D, 64(2): 125-133, March/April 1960. 10 figs. , table, 7 refs. DLC--

Measurements of a 417 megacycles per second unmodulated radio carrier over a 600 mi tropospheric path indicated that the variations of the received carrier enve- lope amplitude with time over 30 min periods roughly approximated a Rayleigh distribution in the majority of tests. Cumulative time distributions of the carrier fade

durations were obtained over a range of carrier envelope power levels and were

found to resemble corresponding distributions for narrow band thermal noise. The

fade rate of the carrier envelope, at the median power level, was less than 0. 2

cycle per sec; this comparatively low fade rate is thought to be due mainly to the narrow (1°) antenna beam width that were used and the consequent low order of

multipath propagation of the radio waves. The half hour median power levels of

the received carrier varied over a range of approximately + 8 db. The effective

low path bandwidth of the carrier spectrum was found to vary from 0. 06 to 0. 17

cycle/sec. The measured median transmission loss was approximately 183 db

which is within 3. 5 db of the calculated value for the summer afternoon hours

covered by the tests. With antennas spaced (normal to path) at each end by 150

wavelengths it was found that parallel path, divergent path, or convergent path

types of transmission gave cross correlation coefficients of the carrier envelopes

which ranged from 0. 08 to 0. 20. For the same antenna spacing but using crossed

path type transmission, the cross correlation coefficient was 0. 57. Diversity

measurements of single path crossed polarization type of transmission indicated

that the cross correlation coefficient of the carrier envelopes was very close to unity. Nondiversity narrow band FSK error measurements, indicated that an 18

db signal to noise power ratio over an effective bandwidth of 290 cycles/sec (at

the limiter-discriminator input) for a fading signal resulted in 0. 8% binary errors and 4. 0% teletype character errors. Extrapolation of these results indicates that

a signal to noise ratio of 27 db is required to reduce the teletype character error rate to 0. 1% in the same effective bandwidth. --Authors' abstract.
180

E-721 Fostoff, B. and litis, J., Faisceauz herziens transhorizon THC 953. (TheT.H.C.

953 transhorizon radio links.) Onde Electrique, Paris, 40(394) :46-57, Jan. 1960.

17 figs. DLC--A new French transhorizon radio link system is described. The

system operates at 450-600 Mc/s and provides 60 telephone channels over distances of several hundred kilometers. Parabolic reflectors 10 meters in diameter

are used. The power amplifiers are ceramic tetrodes with an output of 1 kw. , and

the receivers have a very low noise factor. Double or quadruple diversity is used

to reduce variations in propagation. Air conditioning permits operation of the

equipment under the most severe tropical or desert conditions. --R.M.

E-722 Geiger, G. V. ; La Frenais, N. D. and Lucas, W. J. , Propagation measurements at 3480 and 9640 Mc/s beyond the radio horizon. Institution of Electrical Engineers,

London, Proceedings, Pt. B, 107(36): 531 -546, Nov. 1960. 26 figs. , 7 tables, 7

refs. DLC--The paper gives an account of scatter propagation measurements made

at S and X band during the period May 1957 to May 1959. The work at S band continued throughout the whole of this time, while the X band measurements were made during the period of a year from June 1958 to May 1959. The S band transmitter, using a 3.480 Gc/s c. w. magnetron with a power output of 500 watts, was

established at Start Point in Devon. Receiving terminals were set up at Wembley,

Middlesex, and Witnesham, Suffolk, at distances of 173 and 247 statute miles,

respectively, from the transmitter, the former being maintained in operation

throughout the whole of experimental period and the latter for a period of 9 months

from Sept. 1957 to June 1958. Diurnal and seasonal variations in the median level

of the received signal are discussed and a comparison is made of measurements

taken simultaneously at Wembley and Witnesham. The distribution of S band fading rate as a function of level is studied and a limited amount of work concerned

with the distribution of the duration of fades below a given level and the power

spectrum of the detected signal is described. The transmission path for the X band

system, which used a pulsed magnetron at a frequency of 9. 640 Gc/s, also lies

between Start Point and Wembley; the pulse length was 2 microsec and the pulse

repetition frequency 500 c/s, the peak power in the pulses being 180 kW. The X

and S band links were operated together whenever possible, and a comparison is

made of the median level and fading rate of the signals received simultaneously

at the two frequencies over the same propagation path. In addition, a series of

measurements to investigate the aerial coupling loss of the X band system are described. (Met. Abs. 13. 4-103) --Authors' abstract.

E-723 Gossard, E. E. , Power spectra of temperature humidity and refractive index from

aircraft and tethered balloon measurements. IRE Transactions on Antennas and

Propagation, N. Y. , 8(2):186-201, March 1960. 17 figs. , 4 tables, 24 refs.

16 eqs. DLC--Fifty seven spectra of temperature, vapor pressure and refractive

index were computed from captive balloon data taken at elevations up to 3000 ft MSL. Eight spectra of refractive index were obtained using an aircraft equipped

with a microwave refractometer. It was found that atmospheric stability apparently has a pronounced effect on the variation of turbulent intensity with height. Although the spectra of all three parameters generally approach a -5/3 power law at high wave numbers, stability seems to have a controlling influence on spectral

form at the low frequency end of the wave number range studied. It is therefore

concluded that methods of computing microwave scattered fields from the mean

square dielectric perturbations and scale size obtained from the auto covariance

are unreliable. The forms of the experimental auto covariances appear to be best

represented by an exponential function or perhaps by a Modified Bessel Function

of the second kind and 1/3 order. The temperature humidity cospectrum may influence the shape of the refractive index spectrum, especially under unstable conditions. The equivalence of Eulerian space and time spectra is verified for refractive index in a series of aircraft balloon fly-bys. --Author's abstract.
181

Gough, M. W. (Marconi's Wireless Telegraph Co. Ltd. .Essex), Diurnal influences

in tropospheric propagation. (In: Desirant, M. and Michiels, J. L. (eds.), Electromagnetic wave propagation. London, Academic Press, 1960. p. 557-573. 8 figs.,

14 refs. ) CU-S (QC661. D458) --Attention is given to marked diurnal variations in

signal strength attributable to the nightly occurrence of tropospheric inversion lay- ers promoted by the cooling by radiation of heated ground when the night sky is

clear. After a brief review of observations by various workers, the author appraises 80 Mc/s signal strength recordings maintained continuously for 6 mo over

a 137 km nonoptical path in the Persian Gulf, where the effect persistently occurr- ed to a noteworthy degree. The test path lay mostly over land, between Bahrain

Islands and Doha on the Qatar Peninsula. Modified refractive index profiles, derived from selected meteorological soundings at Bahrain, show the association between (a) very weak signals and an approximately standard atmosphere, and (b)

very strong signals and pronounced elevated or ground based inversions. Theoretical and measured signal strengths are compared. Observations made under ex- ceptional climatic conditions, provide evidence of recurrent nocturnal trapping on

a wavelength which is perhaps longer than has been considered possible. --Author's

abstract and E. Z.S.

Grisdale, G.L.and Paynter, D.A. , A tropospheric scatter link over a 200 mi path. Point to Point Telecommunications, 5(l):34-59, Oct. 1960. 13 figs. , 5 refs. DLC--

This article reviews the performance of an operational link carrying various types

of traffic over a period of one year. The measured signal strengths obtained with

this experimental link agree in the main, with the predicted values. The median

signal strength variation was as high as 80 db. --E.K.

Grudinskaia, Galina Petrovna, Rasprostranenie ul'trakorotkikh radiovoln. (Propagation of ultrashort radio waves. ) 2nd rev. ed. Moscow, Gosenergoizdat, 1960.

103 p. 62 figs. , 6 refs. , 29 eqs. DLC--This book is intended for radio amateurs

and its purpose is to explain the physical aspects of ultrashort wave propagation.

Methods for calculating field intensity in simple cases are described and unsolved

problems in ultrashort wave propagation are indicated. Chapter 4 deals with propagation in the troposphere. Diffraction, refraction and the occurrence of atmospheric ducts, reflection from laminar irregularities in the troposphere and scatter- ing of radio waves from tropospheric irregularities are discussed. Ch. 5 is devoted

to ionospheric propagation of ultrashort waves due to reflection from layers of the

ionosphere and meteor trails, as well as to the scattering of waves by inhomogeneity of the ionosphere. --R. M.

Head, Howard T. , The influence of trees on television field strengths at ultrahigh frequencies. Institute of Radio Engineers, N. Y. , Proceedings, 48(6):1016-

1020, June 1960. 8 figs. , 9 refs. DLC- -Field studies of UHF wave propagation

between television transmitting and receiving antennas indicate that typical woods

are essentially opaque at these frequencies. The signal in the presence of woods

near the receiving antenna appears to be principally that diffracted over the trees,

with a small residual leakage field observable where the diffracted fields are very

weak. The results of measurements are compared with diffraction theory, and the

attenuation below free space fields due to the woods is found to be in good agreement with that predicted for a spherical obstacle having a four-thirds earth's radius.

The conclusions are applied to the estimation of average losses in large areas. --Author's abstract.
182

E-728 Herbstreit, Jack W. , The Ninth Plenary Assembly of the CCIR. Institute of Radio

Engineers, N. Y. , Proceedings, 48(l):45-53, Jan. 1960. 2 refs. DLC --The Inter- national Radio Consultative Committee held its Ninth Plenary Assembly in Los

Angeles, Calif. , April 2 - 29, 1959. The CCIR studies the technical factors af- fecting international radio telecommunications and makes recommendations to administrations which are of importance in the international allocation and usage of

the radio spectrum. These studies are made by 14 Study Groups, each dealing

with certain aspects of international telecommunication. Group V studied the

propagation of radio waves over the surface of the Earth, taking into account

changes in the electrical constants of the Earth and irregularities of terrain, and

including the effects of the troposphere. A new set of radio propagation curves,

giving tropospheric field strength for distances beyond the horizon for frequencies

of 30 to 300 Mo was prepared by an international working party. (Met. Abs.

12. 3-103) -Author's abstract and E. K.

E-729 Hickin, E. M. (Research Laboratories, Gen. Elec. Co. , Ltd. , Wembley, England),

Radio wave propagation and attenuation in the troposphere . Research, London,

13(12): 503-506, Dec. 1960. 5 figs. , 7 refs. DLC, DWB--The study of the atten- uation of radio waves in the troposphere becomes more important as pressure on spectrum space increases. New applications have been discovered for frequencies just above 10 kMc/s and 11,000 Mc/s. Experiments in the U.S. at 10,000

Mc/s have shown that the attenuation by rain at these frequencies is a function

of the diameter of the raindrops, the wavelength and the number of drops per unit

volume of air in the path. Using average rainfall figures for Europe, the author

has constructed a map showing the contours of constant path length for a fixed

time out of service for 11,000 Mc/s radio links in Europe. A figure is also given

showing the attenuation of microwaves by oxygen and water vapor. (Met. Abs.

13. 4-106) -R.B.

E-730 Hirai, Masaichi; Fukushima, Makocla, and Kurihara, Yoshitaka, Correlation

between amplitudes of radio waves of different frequencies in VHF beyond the

horizon propagation . Japan. Radio Research Laboratories, Journal, 7(33):509-

529, Sept. 1960. 7 figs. , 4 tables, 4 refs. , 40 eqs. DBS-Selective fading in

VHF beyond the horizon propagation is caused by the interference between multipath waves. Based on this phenomenon, a correlation coefficient between amplitudes of radio waves of different frequencies is derived theoretically. Relations

of this coefficient with amplitude ratio distribution of multipath wave distribution

are also derived. These relations are examined by use of the experimental data

in 600 and 2120 Mc bands on circuits of 220 km from Kokubunji to Nihonmatsu

and of 345 km from Kokunbunji to Furakawa, and thus the applicability of the

theoretical formulas is illustrated. --Authors' abstract.

E-731 Hirai, Masaichi et al. , Studies in VHF overland propagation beyond the horizon . Japan. Radio Research Laboratories, Journal, 7(31): 137-176, May 1960. 32+ figs.,

8 tables, 14 refs. , numerous eqs. DBS--A series of experiments in beyond the

horizon propagation were conducted over two overland paths (226 and 345 km), using

mainly 159.49, 599 and 2120 Mc, for the period from winter through summer in

1959. The following aspects were investigated: the temporal variation of trans- mission loss, the variation in received power with antenna beam rotated, the

height gain pattern at receiving site, the characteristics of space diversity and

frequency diversity, and the quality of television signal transmission. The principal aim was the study of the mechanism of propagation and the bandwidth capability of the medium. Comparisons of the experimental data with the theoretical

values suggest favorable applicability of the theoretical formulas in estimating

the propagation characteristics. --Authors' abstract.
183

E-732 Hirai, Masaichi; Inoue, Ryosuke and Kido, Yoshihisa, Variation in received

3ignal power with narrow beam antennas rotated horizontally in UHF beyond the

horizon propagation. Japan. Radio Research Laboratories, Tokyo, Journal, 7(33):

487-507, Sept. 1960. 14 figs. , table, 9 refs. , 32 eqs. DLC. Also Japanese

version in their Review, 6(26):251-260, Sept. 1960. DBS --In UHF beyond the

horizon propagation, the variation in received signal power with narrow beam an- tennas rotated does net only depend on the patterns of antenna directivities, but

also on the mode of propagation, the geometrical feature of propagation path and

the method of antenna rotation. Theoretical formula on the above variation in re- ceived signal power is derived under the assumption of tropospheric scatter propagation, and its comparison with experimental data indicates fairly good coincidence. (Met. Abs. 14. 4-123) -Authors' abstract.

E-733 Hiser, H. W. and Ray, P. R. , Weather radar receiving system. Miami. Univ. (at

Coral Gables). Marine Lab. , Contract NOas 59-6217-C, Final Report, June 17,

1959 to June 17, 1960, pub. July 1960. 50 p. 16 figs. , 4 tables, 21 refs. , 21

eqs. DWB- -Calibration procedures and tests of a Range Attenuation Corrector and

a video inversion type Isoecho Contour device developed under previous contracts

are described and sources of error are discussed. Some theoretical aspects of

range attenuation correction are presented which include a discussion of the use

of logarithmic receivers and the problems of beam filling, earth shadow, and re- flections. A brief description of a new developmental weather radar receiver system, which is being procured under the FY-1960 contract, is given. Statistical

results of a precipitation echo height study based upon data from an MPS -4 height

finder radar are presented and the application of this echo height information to the range attenuation correction problem is discussed. A general discussion of

laboratory activities and performance is also included. (Met. Abs. 14B-74)

--Authors' abstract.

E-734 Hoffman, J. D. , A thin route beyond the horizon VHF system in the Middle East. IRE Transactions on Communications Systems, N. Y. , 8(4):263-271, Dec. 1960.

16 figs. , 3 tables, 9 refs. DLC--The application of thin route technique in an economical integrated small scale VHF system in the 156 - 174 Mc band is described. The system provides point to point multi channel voice, teletype and

mobile communications between the main office of the Trans-Arabian Pipe Line

Co. in Beirut, Lebanon, and pumping stations and mobile units along the route

of the pipe line through Lebanon, Syria, Jordan and Saudi Arabia. In addition,

supervisory control and telemetering of 5000 HP combustion gas turbine pumping

installations over portions of the system, including a 120 mi long link, is described. The terminals of this link and others, 90 to 105 mi long, are well beyond the horizon. --From author's abstract.

E-735 Ikegami, F. , A preliminary study of radiometeoroloqical effects on beyond hori- zon propagation. U.S. National Bureau of Standards, Journal of Research, Sec.D,

64(3): 239-246, May/June 1960. 11 figs. , 13 refs. , 3 eqs. DLC, DWB--A study

was made of American and Japanese radiometeorological data in order to suggest

the dominant factors in propagation beyond the horizon. The diurnal variability

of radio field strength seems to be sensitive to the crossover height of rays tan- gent to the radio horizon and disappears for crossover heights greater than about

500 m. High hourly median field strength were observed in Japan corresponding

to the existence of a marked refractive index discontinuity layer in a common

volume of two antenna beams. The results of these experiments suggest that

laminar structures of the atmosphere play an important role in beyond horizon

radio propagation. (Met. Abs. 11. 10-49) —Author's abstract.
134

E-736 Janes, H.B. ; Stroud, J. C. and Decker, M.T. , An analysis of propagation measurements made at 413 megacycles per second well beyond the radio horizon

(a digest). U.S. National Bureau of Standards, Journal of Research, Sec. D,

64(3):255-257, May/June 1960. 2 figs. , 3 refs. DLC, DWB- -During an 18 mo

period in 1952 and 1953, transmission loss measurements at 418 megacycles

were made over a 134 mi path between Cedar Rapids, Iowa, and Quincy, III. Continuous recordings made simultaneously at several receiving antenna heights

from 30 to 865 ft yielded information on diurnal and seasonal variations in both

the hourly median basic transmission loss and in height gain. These data are compared to predictions made using the method developed by Rice, Longley, and

Norton and are found to be in good agreement, particularly at the lower antenna

heights. An analysis of the correlation of short term signal level variations observed at horizontally and vertically spaced antennas is described. (Met. Abs.

11. 10-48) -Authors' abstract.

E-737 Johler, J. R. ; Walters, L.C.and Lilley, CM., Amplitude and phase of the low

and very low radio frequency ground wave. U.S. National Bureau of Standards,

Technical Note, No. 60, June 1, 1960. 40 p. 8 figs. , 26 tables, 4 refs. DLC--

Graphs and tables of the low and very low radio frequency ground wave are presented as a function of frequency, 100 c/s to 1000 kc. --Authors' abstract.

E-738 Kalinin, A. I. , Dal'nee troposfernoe rasprostranenie ul'trakorotkikh voln. (Long

distance tropospheric propagation of ultra short waves.) Elektrosviaz', Moscow,

14(6):39-49, June 1960. 13 figs. , 3 refs. , 7 eqs. Transl. into English in Radiocommunications, N. Y. , No. 6, 1960. DLC --A review of experimental findings on

tropospheric propagation of ultrashort waves based on English language papers.

Emphasis is placed on signal characteristics including slow and fast fades, dependence of signal level on distance, wavelength, antenna orientation and height,

wave polarization, dielectric constant of the air, and meteorological conditions.

Loss in antenna gain, an operating frequency band, and signal distortion are also

considered. --R. M.

E-739 Kalinin, A.I. , Dal'nee troposfernoe rasprostranenie UKV; teoreticheskie ob"iasneniia eksperimental'nykh rezul'tatov. (Long distance tropospheric propagation

of USW; theoretical explanations of experimental results.) Elektrosviaz', Moscow,

14(7):38-46, July 1960. 8 figs. , 10 eqs. Transl. into English in Radiocommunications, N. Y. , No. 7, 1960. DLC --This paper is a follow up on one by the same

author containing experimental data on extended range propagation of ultrashort waves. Here, the author presents theoretical explanations of experimental data.

Theories of the phenomenon of tropospheric scatter propagation are briefly re- viewed and signal amplitude as a function of various parameters is discussed.

The widening of antenna directivity patterns and the phenomenon of losses in

antenna gain are briefly explained. The importance of tropospheric radio relay

links is mentioned. --R. M.

E-740 Kalinin, Iu. K. , Nekotorye voorosy rasprostraneniia radiovoln nad neodnorodnoi

sfericheskot poverkhnosti'iu Zemli . (Some problems of radio wave propagation

over the heterogeneous spherical surface of the Earth. ) Akademiia Nauk SSSR.

Institut Zemnogo Magnetizma, Ionosfery i Rasprostraneniia Radiovoln, Trudy,

No. 17(27): 50-129, 1960. 38 figs. , table, 45 refs. , eqs. DLC -Propagation of

radiowaves around the Earth is analyzed with special emphasis on heterogeneous

properties and boundary conditions of the terrestrial surface. Radiowave propagation along coastal lines is given special attention. A comparison of theoretical
185

and experimental data, available from literature gives satisfactory results. The

analysis may be particularly useful for correcting errors introduced by electric

heterogeneities into the operation of radio navigational systems working on ground waves and for providing some useful directions to radio bearing stations.

--S.N.

Katzin, M. ; Pezzner, H. ; Koo, B. Y.C.etal., The trade wind inversion as a transoceanic duct. U.S. National Bureau of Standards, Journal of Research,

Sec. D, 64(3): 247-253, May/June 1960. 6 figs. , 4 tables, 6 refs. , eq. DWB,

DLC--Radiosonde data for stations in the South Atlantic trade wind belt are analyzed to determine the potentialities of the trade wind inversion as an elevated duct for transoceanic radio transmission. These were supplemented by

refractometer soundings made by an aircraft during the latter part of 1958. These

records indicate that a duct is present in the majority of the cases. Since it is

known that the radiosonde underestimates ducting because of its slow response,

it is concluded that a duct is present practically all the time. On the basis of

the data analyzed, an experiment with two aircraft is suggested to test the pro- pagation potentialities of this mechanism. A frequency of around 200 megacycles per second appears to be a good choice for an initial experiment. (Met.

Abs. 12. 3-349) --Authors' abstract.

Kinber, B. E. , O medlennykh zamiranii siqnala pri troposfernom rasseianii . (On

slow fading of signals in tropospheric scattering. ) Radiotekhnika i Elektronika,

Moscow, 5(3):521-522, March 1960. Fig., 8 refs. , 3 eqs. Transl. into English

in Radio Engineering and Electronics, N. Y. , 5(3):237-239, 1960. DLC--It has

been shown that the mean hourly signal level in tropospheric scattering obeys

log normal distribution. The author demonstrates that this distribution may be

obtained on the basis of the hypothesis that slow fades o( the signal are linked

with changes in refraction (gradient of permittivity of the air;. Mean square deviations of slow fades are represented graphically as a 'unction of path length.

-R.M.

Knudtzon, N. H. and Gudmandsen, P. E. , Results from a three hop tropospheric

scatter link in Norway with parallel operations on 900 Mc and 2200 Mc . IRE

Transactions on Communications Systems, N. Y. , 8(l):20-26, March 1960. 10

figs. , ref. DLC--From measurements on a 360 km hop in the period Oct. 1957 to June 1958, it is concluded that: 1) the monthly amplitude distributions are approximately Gaussian, and the 1 min amplitude distributions are of the Rayleigh

type, 2) the signals are generally considerably stronger in summer than in winter,

3) the monthly median strength of the 900 Mc signals is generally stronger than

that of the 2200 Mc signals, 4) the foreground conditions may be critical, 5) the

1 min fade duration distributions are approximately log normal, 6) the normalized

1 min fade duration distributions are about equal for 900 Mc and 2200 Mc, 7) con- siderable reductions in telegraph error rate are affected by increasing orders of

diversity reception, 8) the telegraph error rates are equal for 900 Mc and 2200

Mc signals of equal medium strength, 9) frequency modulated telegraph multiplex equipment is slightly superior to two tone telegraph multiplex equipment,

when adjusted to equal loadings, 10) antenna radiation diagrams depend criti- cally on local surroundings, such as woods. --Authors' abstract.
136

E-744 Koch, G.F. , Die verschiedenen Ansatze des Kirchhoffschen Prinzips und ihre

Anwendunq auf die Beugunqsdiaqramme bei elektromaqnetischen Wellen. (Differ- ent methods based on Kirchhoff's principle and their applications to the refraction

diagram in the case of electromagnetic waves. ) Archiv der Elektrischen Ubertragung, Stuttgart, 14(2):77-98, Feb. 1960 and 14(3): 132-153, March 1960. 39 figs. , 53 refs. , 221 eqs. German and English summaries. DLC --Following a brief review

(Sec. I) of the possibilities of accounting analytically for the diffraction problems

encountered at microwave frequencies, a short outline (Sec. II) is given of the

methods using the statement of Kirchhoff, which have most practical importance,

and the methods are applied for diffraction at a diaphragm and at a disk (reflector).

The results are stated for the far field of the diffraction wave in the illuminated and

nonilluminated spaces of diaphragm and reflector with the scalar methods of Kirchhoff, the tvvo scalar methods of Sommerfield, the vectorial method of Franz, and the

two vectorial methods of Luneberg. The features of these methods, of v/hich under

certain conditions the vectorial methods yield the same results as the corresponding scalar methods, are pointed out and their differences studied in detail (Sec. III). On the basis of experimental results the capabilities of the various methods are checked, above all with oblique incidence, for in this case the differences between

the various methods are far greater than with vertical incidence, and the influence

of the polarization makes itself felt far more strongly, whereas with vertical incidence it is but slight. The so-called revolving mirror test allows a simple presentation of the diffraction diagrams with vertical incidence, and permits conclusions

to be drawn with respect to the diffraction diagrams with oblique incidence in the

plane of incidence. A direct measurement of the diffraction diagrams with oblique

incidence confirms these conclusions: furthermore the value of the results of the

methods is studied with reflectors of the order of several wave lengths, as well as

the influence of the polarization of the incident wave. The investigations showed

as a rule a superiority of the scalar statement of Kirchhoff and the vectorial state- ment of Franz, in particular with cases of oblique incidence, which are critical

with respect to polarization. The experimental investigations, which were only

made for the plane incidence, also allow conclusions to be drawn with respect to the capabilities of the methods outside the plane of incidence, however (Sec. IV).

From the results of the experiments Sec. V draws some conclusions for the handling

of Kirchhoff's approximation methods. In Sec. VI consideration is given to the re- flection at reflectors of the order of a few wavelengths, investigations and calculations are stated concerning the surface utilization and conclusions are drawn from

the capabilities of the approximation methods as to the calculation of the reflecting cross sections of plane reflectors. (Met. Abs. 12. 5-67) --Author's abstract.

E-745 LaGrone, Alsfred H. , Forecasting television service fields. Institute of Radio

Engineers, N. Y. , Proceedings, 48(6): 1009-1015, June 1960. 10 figs. , 3 tables,

foot-refs. DLC --The propagation of VHF and UHF television signals over a spherical, irregular surface such as the earth, is examined theoretically and experimentally and the principal factors evaluated. The principal factors are found to be

frequency, meteorology, terrain and vegetation. It is shown that meteorology, ter- rain and vegetation vary a significant amount geographically and the local values

should be used in forecasting local service fields. The principal factors are in- cluded in a new empirical method suggested for forecasting the service fields of

television stations. The signal forecast by the new method is compared with field

measured signals with good results. --Author's abstract.
137

Laurens, A.; Koenig, J. D. and Carzan, C. , Essais de transmission au-dela de

l'horizon d'images de television a 4000 MHz. (Over the horizon transmission of

television signals at 4000 MHz.) Onde Electrique, Paris, 40(394): 106-111, Jan. 1960. 11 figs. , table, 3 refs. French and English summaries. DLC--The authors

first compare 800 and 4000 Mc/s frequencies for over the horizon transmission of

television signals, particularly from the point of view of signal to noise and bandwidth obtained. They then describe an experimental system operating at 4000 Mc/s

over a distance of 220 km. Finally, they discuss the results obtained and analyze

the recordings made. (Met. Abs. 12. 1-103) --Authors' abstract.

Lemoine, P. , Un combineur de diversite pour liaisons transhorizon . (Diversity

mixer for beyond-the -horizon links. ) Onde Electrique, 40(394): 112-115, Jan. 1960.

Fig. , 2 refs. DLC --After a review of the general principles of diversity systems,

various existing systems are compared, and the system adopted by the Compagnie

Generale d'Electricite is described. The C. G.E. system is based on the principle

of the combination into a basic band of a group of 2 channels, and uses a standard cathode mixer. The signal-noise ratio of the combined channel differs by less

than 0. 5 db from the optimum signal-noise ratio. The system operates correctly

at noise levels from +25 db to —40 db in relation to the threshold noise level. The

total harmonic is less than —70 db for signal levels differing by 1 db in the channels to be combined. The time of response of the system is less than 5 ms/c.

--R.M.

Lotova, N. (Acad. Scien. , U.S. S. R. ), On estimating the angle of scattering of

radio waves. Soviet Astronomy AJ, New York, 3(5):881-383, March/April 1960.

3 refs. , 3 eqs. Transl. of her K otsenke ugla rasseianiia radiovoln in Astronomicheskii Zhurnal, Moscow, 36(5):907-909, Sept. /Oct. 1959. DLC -An expression

is derived for the dispersion of the angle of scattering of a plane electromagnetic

wave in a statistically nonuniform medium. A discussion is given of the case where the dispersion of the refractive index is a slow function compared with the

dimensions of statistical irregularities. (Met. Abs. 12. 6-162)--Author's abstract.

Mackey, C.L. (Rome Air Devel. Center, Griffiss AF Base, Rome, N.Y.), Tropospheric scatter developments. (In: Desirant, M. and Michiels, J.L. (eds.), Electromagnetic wave propagation. London, Academic Press, 1960. p. 685-697. 16

figs.) CU-S (QC651. D458) --Developments in the field of tropospheric scatter

equipment are reviewed and advances in the state of the art in power klystrons,

diversity, solid state devices, antennas, modulators, and miniaturization techniques for mobile application are discussed and areas of future investigation are indicated. --Author's abstract and E. Z.S.

McLeish, C. W. , Measurements of coastal deviation of high frequency radio waves. U.S. National Bureau of Standards, Journal of Research, Sec. D, 64(1):

57-59, Jan. /Feb. 1960. 3 figs. , 2 tables, 8 refs. , eqs. DWB, DLC -The angular

deviation of the phase front of a wave propagated across a fresh water shoreline

has been measured over the frequency range from 3 to 20 Mc. The deviation is

found to be roughly half that which theoretically would be obtained if the same

sites were adjacent to infinitely conducting surfaces. (Met. Abs. 14.4-114)

--Author's abstract.
188

E-751 Martin, S.J. (Hughes Aircraft Co. , Fullerton, Calif.), Note on scatter propagation . Institute of Radio Engineers, N. Y. , Proceedings, 48(11):1915-1916, Nov. 1960.

Fig. DWB--Discusses experimental results of tropospheric forward scatter trans- mission as conducted at 400 and 800 Mc/s over the 156 mi over sea path, Key

Marathon, Fla. and Jaruco, Cuba, aimed at determining (1) the variation in fading

rates as a function of antenna elevation, (2) the variation in frequency selective

fading as a function of frequency separation of two side bands, and (3) the effects

of antenna beam width on path mult. path. (Met. Abs. 13. 4-107)--W. N.

E-752 Misme, P. (Centre Nat'l. d'Etudes de Telecommun. , Paris), (Comment on) B.R.Bean

and C. D.Thayer: Models of the atmospheric refractive index (and reply by) Bean

and Thayer. Institute of Radio Engineers, N. Y. , Proceedings, 48(8): 1498-1499,

Aug. 1960. Figs. , tables, 16 refs. , eqs. (For abstract on original article, see

E- 614). DLC -MISME questions BEAN and THAYER's expression N(h) = No exp ah,

which he attempts to show is restricted to certain regions only. In a set of critical

tests of Misme 's hypothesis that s < lOg/kg is a prerequisite for a good correlation

between Ns and beyond the horizon radio fields, BEAN and THAYER's results indicate that their exponential model is reasonably applicable since the N structure is

generally representative for the first km wherever applied under a variety of geographical (hence climatological) conditions. (Met. Abs. 13. 6-100) --W. N.

E-753 Misme, P. , Influences radioclimatigues sur les liaisons transhorizon. (Influence

of radio climatic conditions on over the horizon links.) L'Onde Electrique, Paris,

40(394): 116-123, Jan. 1960. 13 figs. , 3 tables, 13 refs. French and English summaries. DLC --The author begins with the radioclimatic effects on over the horizon

propagation, and on the interference that a transmitter may produce on an existing

system. He then develops the idea of the useful gradient of the refractive index

and shows that this parameter is more representative of the atmosphere than the

difference between the indices at levels of zero and 1000 m. The forms which are taken by the refractive index as a function of height are considered theoretically

and experimentally, and it is shown that this is not an exponential function. The

form is quasi-exponential within following regions: 1°) the polar caps, extended

to the zones, where, for a great percentage of days in each month, the soil temperature is lower than 14°C; 2°) the temperate zones during winter; 3° the deserts, hot during daytime; 4°) the altitudes higher than the surface s = 10 g/kg

(s = specific humidity); 5°) certain temperate zones during the whole year. One

can consequently determine a priori, when in more than half of the globe the index

gradient at a place is a function of the refractive index at the same spot. From

this it is deduced that a good correlation between the refractive index and its gradient is not likely to exist in the lower atmosphere layers. This article also calls

attention to other important radioclimatic parameters which are still little studied,

for example, the stability of the atmosphere. (Met. Abs. 12. 1-104) --A. V. and

author's abstract.

E-754 Misme, P. , Le gradient equivalent, mesure directe et calcul theorique. (Equivalent gradient, direct measurement and theoretical calculation. ) Annales des Telecommunication, 15(3/4) :92-99, March-April 1960. 8 figs. , tables, 5 refs. -First

the concept of equivalent gradient is determined. The application of this definition yields an easy method to measure its quantity by means of radio. The theoretical calculation of equivalent gradient is then presented and the method used is

adapted to the climate of Niamey (Nigeria). The order of magnitudes then found

prove that values of equivalent gradient vary according to the type of propagation

(scattering, diffuse reflection, or specular reflection), and according to the length

of path of a link. --Transl. of author's abstract.
189

Moler, William F. and Holden, D.B. , Tropospheric scatter propagation and atmospheric circulations. U.S. National Bureau of Standards, Journal of Research, Sec.

D, 64(l):81-93, Jan. /Feb. 1960. 16 figs. , table, 15 refs. , eqs. DWB, DLC--

Transhorizon VHF and UHF fields exhibit deep fades or large signal enhancements

of several hours' duration, as the propagation mechanism alternates between partial

reflection and scattering caused by turbulent dielectric fluctuations in the atmosphere. Such alternations occur when strong refractive layers develop below 3000

ft. Surface wind streamline analyses show that mesoscale centers of convergence

or divergence cause local redistribution of refractive layering, tending to produce

the change from one mechanism to the other. Current scattering theory and the empirical findings of others are examined to determine the gross meteorological fac- tors that influence changes in scattered fields. The two variables in the turbulent

scattering coefficients, the scattering angle and the intensity of dielectric fluctuations at high wave numbers, are found to be dependent upon the refractive layering

and the thermal stability of the air mass. It has been shown elsewhere that refractivity and stability are principally functions of the vertical velocity in the atmosphere. It is shown here that the direction and relative magnitude of the vertical

velocity can be inferred from the upper tropospheric wind velocity divergence. Received scattered signals are found to be well correlated with computed velocity

divergence. It is suggested that the variations of scattered signal level or range can be predicted in a routine manner by regular meteorological personnel using

ordinarily available meteorological data. (Met. Abs. 13. 9-113) --Authors' abstract.

National Research Council, Wash. , D.C. , U.S. National Committee on the International Scientific Radio Union, Report of U. S. Commission 2 on Tropospheric Radio

Propagation, to the 13th General Assembly of the ISRU. London. Sept. 5-15. 1960. U.S. National Bureau of Standards, Journal of Research, Sec. D, 64(6):607-627,

Nov. /Dec. 1960. Bibliog. of papers published since the 12th General Assembly,

p. 622-627. DWB, DLC--This report contains a brief summary of the work of the

U.S. National Committee of Commission II on Tropospheric Radio Propagation ar- ranged in accordance with the topics to be discussed at the XIII General Assembly

in London 1960. The bibliography includes principally the papers published since

the XII General Assembly. The topics include the physical characteristics of the

troposphere, theories on the tropospheric propagation, experimental results from

investigation of tropospheric propagation and radio meteorology. (Met. Abs.

12. 8-11D--E.Z.S.

Nemirovskii, A.S., O prieme so slozheniem signalov raznesennykh po uglu prikhoda lucha. pri dal'nem troposfernom rasprostranenii ukv. (Reception involving

the combining of signals with diversity based on the beam angle of arrival under

conditions of long range UHF tropospheric propagation.) Elektrosviaz', Moscow,

14(8): 19-25, Aug. 1960. 11 figs. , 8 refs. , 16 eqs. Transl. into English in Radiocommunications, N. Y. , No. 8, 1960. DLC--The author presents a new method of

diversity reception for long range UHF tropospheric links based on diversity with

respect to the beam angle of arrival in the horizontal and vertical planes. Angular

diversity is effective only for high directivity antennas and yields higher values

of improvement in the horizontal plane than in the vertical plane. Graphs show

the improvement as a function of the half power width of the antenna directivity

pattern and the reliability of ordinary reception. --Transl. of author's abstract

-R.M.
190

E-758 Norton, Kenneth A. (Boulder Labs. , Boulder, Colo.), Carrier frequency depend- ence of the basic transmission loss in tropospheric forward scatter propagation . Journal of Geophysical Research, Wash. ,D.C. , 65(7): 2029-2045, July 1960. 3

figs. , 3 tables, 19 refs. , eqs. DLC--A further interpretation is given of certain

Lincoln Laboratory data obtained in an experiment using scaled antennas as published by BOLGIANO (1959). This paper has three objectives: 1) to consider the

significance of these data as regards the theory of radio propagation through a turbulent atmosphere; 2) to describe a suitable method for the measurement of

the meteorological parameters entering the theory; 3) to apply a further statistical analysis to these data. On the basis of this analysis of the Lincoln Laboratory data, it is concluded 1) that the

h/r

(£)J

(/V2) AK ^{p)

correlation model provides a description of tropospheric turbulence adequate for the description of these data with /u. assigned the fixed value 1, and 2) that the

variation of the carrier frequency dependence of the basic transmission loss from

hour to hour arises simply from a lack of correlation in the hourly median losses

on widely separated carrier frequencies rather than from changes of pn. in this cor- relation model. (Met. Abs. 12. 9-109)--Author's abstract.

E-759 Olivier, M. and Pellerin, J. , Le faisceau hertzien Medea-Laqhouat-Ouarqla.

(The Medea-Laghouat-Quargla radio link.) Onde Electrique, 40(394): 32-38, Jan. 1960. 12 figs. DLC --Description of a 450 Mc/s radio link in Algeria. The system, 604 kilometers in length, includes a number of repeater stations using over- the-horizon propagation. Criteria used in the selection of equipment and the measures taken to ensure reliability of operation are discussed. The system is basically the TH 949 system, modified to fit local conditions. The modifications include the addition of a UHF preamplifier to reduce the noise factor, the design of

buildings and towers, and special equipment to ensure continuous operation of

the system. --R. M.

E-760 Parry, C.A. , Criteria for the ultimate capability of the optimized tropospheric

scatter system. IRE Transactions and Communications Systems, N. Y. , 8(3):187-

192, Sept. 1960. 12 figs. , table, 8 refs. , 8 eqs. DLC-Behavior of the tropospheric scatter mechanism is now sufficiently well understood to permit a determination of optimum transmission criteria. The requirements for optimazation are established from the channel signal to noise ratio equation. It is shown that the

optimum is related, not only to the basic RF transmission loss, but also to the

effective noise figure, antenna gain and medium aperture loss. --From author's

abstract.

E-761 Petrovskii, A. D. and Feinberg, E.L., O priblizhennom qranichnom uslovii v

teorii rasprostraneniia radiovoln vdol' Zemli. (On the approximate boundary condition in the theory of radiowave propagation along the Earth. ) Radiotekhnika i Elektronika, Moscow, 5(3):385-388, March 1960. Fig., 6 refs. , 9 eqs. Transl.

into English in Radio Engineering and Electronics, N. Y. , 5(3):43-48, 1960. DLC--

Homogeneous boundary conditions are formulated for the field in the problem of

radiowave propagation along the Earth at large distances from the source and from

disturbances of homogeneity of the surface, remaining valid for the case of complex dielectric constant close to unity. --Authors' abstract.
191

Pluchard, A. G. , Le programme d'equipment en faisceaux hertziens transhorizon

de l'Alqerie et du Sahara. (Program for the establishment of over-the-horizon radio

links in Algeria and the Sahara.) Onde electrique, Paris, 40(394): 19-23, Jan. 1960. 2 figs. DLC--The need for over-the horizon radio links in Algeria and the

Sahara is discussed. Local problems, such as climatic conditions, power supply,

and maintenance, are reviewed. Criteria used in the selection of the station sites,

requirements for equipment (including towers and antennas), and stations are described. The need for propagation tests is stressed. --R.M.

Priimak, G.I. , Korreliatsionnaia funktsiia siqnala. proshedsheqo sredu s khao- ticheski dvizhushchimisia neodnorodnostiami. (Correlation function of a signal

passing through a medium with randomly moving inhomogeneities. ) U.S.S. R.

Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii,

Radiofizika, 3(5): 778-788, 1960. 3 refs. , 44 eqs. DLC--The problem of correlation function of a signal passing through a medium with randomly moving inhomogeneities is analyzed theoretically. Although the analysis is primarily concerned

with acoustical signals, it equally applies to radio wave propagation. --Transl. of

author's abstract. -G. T.

Prosin, A.V., K teorii perekrestnykh iskazhenii pri dal'nem troposfernom rasprostranenii ukv. (On the theory of cross distortion with long distance tropospheric

UHF propagation. ) Radiotekhnika i Elektronika, Moscow, 5(7): 1052-1964, July

1960. 6 figs. , 10 refs. , 56 eqs. Transl. into English in Radio Engineering and

Electronics, N. Y. , 5(7):27-45, 1960. DLC -The author considers a method for

calculating cross noise occurring in multichannel long distance systems with fre- quency modulation and frequency division multiplex due to the interaction of the

constant and scattered fields at the point of reception. --Transl. of author's abstract. -R.M.

Prosin, A.V., O zavisimosti moshchnosti rasseianiia ot napravlennosti antenn. (Dependence of scattered power on antenna directivity. ) Radiotekhnika i Elektronika, Moscow, 5(2):330-333, Feb. 1960. 2 figs. , 7 refs. , 7 eqs. Transl.

into English in Radio Engineering and Electronics, N. Y. , 5(1):215-219, 1960.

DLC--Evdokimov has found that for tropospheric propagation it is more efficient to use antennas with greater horizontal directivity than vertical directivity. (See

ref. E-574). On the basis of his earlier work, the author of this note demonstrates that the opposite is true, i. e. , an antenna with greater vertical directivity

is the more efficient even though in a limited area antenna directivity in the horizontal plane has a greater effect on antenna gain losses. --R. M.

Prosin, A.V., O zavisimosti moshchnosti rasseianiia ot statisticheskikh kharakteristik turbulentnoi* troposfery. (Dependence of the amount of scattering on sta- tistical characteristics of tropospheric turbulence.) Elektrosviaz', Moscow,

14(12):3-10, Dec. 1960. 3 figs. , table, 5 refs. , 14 eqs. Transl. into English in

Telecommunications, N. Y. , No. 12, 1960. DLC--On the basis of a correlation

function and assuming an arbitrary gradient of dielectric transmissivity fluctuation, a generalized method of calculating the amount of scattering and the reduc - tion of antenna gain for both directional and nondirectional antennas is developed.

The formula obtained are found to make it possible to investigate, in general terms,

the dependence of the amount of scattering and the reduction of antenna gain on

statistical characteristics of atmospheric turbulence, and also to compare results

of various theories of scattering. --Transl. of author's abstract.
192

E-767 Prosin, A.V. , Perekrestnye iskazheniia v mnoqokanal'nykh sistemakh sviazi s ChM, voznikaiushchie pri rasseiannom rasprostranenii UKV. (Intermodulation

distortion in multichannel links with FM in USW scatter propagation. ) Radiotekhnika, Moscow, 15(8):3-12, Aug. 1960. 8 figs. , 13 refs. , 53 eqs. Transl. into

English in Radio Engineering, N. Y. , 15(8):1-17, 1960. DLC --The author develops

a method for computing the cross distortion due to multibeam scatter propagation

of ultrashort waves in multichannel FM systems with frequency division multiplex.

Formulas are derived for determining the cross noise power. The relationship between cross distortion and the path length, the width of the antenna directivity

patterns, and a number of other characteristics is established. --Transl. of author's

abstract. --R.M.

E-768 Remizov, L.T. ; Golubtsov, M.G.and Tiufiakin, L.S., Priemnoe ustroYstvo dlia

izmereniia statisticheskikh kharakteristik siqnalov pri troposfernom rasprostranenii

radiovoln . (Receiving equipment for the measurement of statistical signal characteristics with tropospheric propagation of radio waves. ) Radiotekhnika i Elektronika, Moscow, 5(7): 1065-1071, July 1960. 9 figs. , 3 refs. Transl. into English in

Radio Engineering and Electronics, N. Y. , 5(7):46-56, 1960. DLC -The paper contains a brief description of a receiver designed for simultaneous recording of the

variations in the level of sinusoidal signals at three frequencies with a discretely

varying interval between them. Considerations in selecting the basic parameters

of the receiver and some results of tests are set out. A block diagram of the unit

is included. --R. M.

E-769 Rubinshtein, la. M. , Rasprostranenie radiovoln i antenno-fidernye ustroYstva.

(Radiowave propagation and antenna feeder equipment. ) Leningrad. Izd-vo Morskoi

Transport, 387 p., 1960. Figs., tables, 55 refs. , eqs. DLC -This book deals with

problems relating to the theory and design of antenna feeder systems of both coastal

and naval radio stations. Emphasis is on medium and short wave equipment. In connection with possible long distance and worldwide communications systems,

ionospheric conditions and the absorption, reflection, and refraction of radio

waves in the ionosphere are discussed. One of the 14 chapters is devoted entirely to ultrashort wave propagation and antennas for this purpose. In it, field

strength in the far zone, fading of signals, tropospheric scatter, and other problems are considered. Space diversity reception is also explained. --R.M.

E-770 Salomonovich, A. E. and Ataev, O. M. , Teplovoe izluchenie i poqloshchenie v zemnoi atmosfere radiovoln 8 mm diapazona . (Thermal radiation and atmospheric

absorption of 8 mm radio waves.) U.S.S. R. Ministerstvo Vysshego Obrazovaniia,

Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 3(4):606-613, 1960. 7 figs.,

12 refs. , 11 eqs. DLC --Values of molecular absorption of 8 mm radio waves were

obtained from data of proper thermal radiation of the Earth's atmosphere. In obtaining these values a spherically symmetrical model of a moist atmosphere was as- sumed, neglecting absorption and scattering by condensation products. For clear

days, which are in good agreement with this model, the following values of absorption coefficient are obtained for oxygen 0. 0046 neper/km (0. 04 db/km); for water

vapor 0. 00046 neper/km (or 0. 004 db/km), for each g/m^. With the help of these

values the total absorption of 8 mm radio waves may be obtained from data on absolute humidity and path length. --Transl. of authors' abstract. -G. T.
193

E-771 Saxton, J. A. (Radio Res. Station, Ditton Park, Slough, England), Quelques reflexions sur la propagation des ondes radioelectriques a travers la troposphere. (Some

reflections on the radio wave propagation through the troposphere.) Onde Electrique, Paris, 40(400/401): 505-514, July/Aug. 1960. 3 figs. , 58 refs. DLC--After

an historical sketch of developments in the study of long distance tropospheric

propagation and a summary of the propagation characteristics for frequencies above

30 Mc/s, the writer analyzes present day knowledge about tropospheric diffusion.

Recent investigations are described and arguments advanced for a theory which considers propagation beyond the horizon as being based on a troposphere layer rather

than solely or even principally upon atmospheric turbulence. (Met. Abs. 13. 3-98)

--Author's abstract.

E-772 Spizzichino, A. , Reflexions partielles dans l'atmosphere et propagation a qrande

distance. VI. Les differentes composantes du champ au dela de l'horizon . (Partial

reflections in the atmosphere and long distance propagation, Pt. 6, The various

components of the field beyond the horizon.) Annales des Telecommunications,

Paris, 15(5/6): 122-136, May/June 1960. 13 figs. , 15 refs. DLC- -The author first reviews the results given in the previous articles dealing with reflections by ir- regular surfaces and shows how they may be applied to tropospheric reflections.

He takes as a basis these results and those of the classical diffusion theory to compare the reflection and diffusion phenomena. The characteristics of the fluctuations of the reflected field and of the diffused field are very different, so that

they can be easily recognized. Experience shows that the field received beyond

the horizon sometimes has the characteristics of a reflected field and sometimes

those of a diffused field. All the practical consequences of the coexistence of

these two phenomena are finally derived- (See refs. E-542, 528, 785, 786, 715)

(Met. Abs. 13. 1-12D-A. V.

E-773 Springer, P. and Rawhauser, R. (both, Wright Patterson AF Base, Dayton, Ohio),

Instantaeous electronic ray tracing computer for the solution of electromagnetic

propagation problems. (In: Desirant, M. and Michiels, J.L.(eds.), Electromagnetic wave propagation. London, Academic Press, 1960. p. 227-242. 20 figs.

CU-S (QC661. D458) --Describes a new analog computer capable of providing in- stantaneous ray tracing solutions to the Wave Propagation Equation developed for the Wright Air Development Center. With this computer and current refractive index

profiles it is possible to determine tropospheric propagation conditions while they

exist. Excellent correlation between ray tracing predictions and measured propagation data was obtained. --Authors' abstract and E. Z. S.

E-774 Stanley, Glenn M. , Layered earth propagation in the vicinity of Point Barrow.

Alaska . U.S. National Bureau of Standards, Journal of Research, Sec.D, 64(1):

95-97, Jan. /Feb. 1960. 4 figs. , 4 refs. , 10 eqs. DWB, DLC -The relative field

strength of a vertically polarized low frequency radio signal was measured as a function of distance over several radial paths in the vicinity of Point Barrow, Alaska.

The attenuation of the recorded signal was very much less than predicted by the

theory of propagation of a ground wave signal over a plane, homogeneous, infinitely

conducting earth. The analysis of these data in terms of a plane, layered, finitely

conducting earth appears to resolve the anomaly. (Met. Abs. 14. 4-115)--Author's

abstract.
194

E-775 Straiton, A. W. and Tolbert, C. W. , Anomalies in the absorption of radio waves by

atmospheric gases . Institute of Radio Engineers, N. Y. , Proceedings, 48(5):898-

903, May 1960. 5 figs. , table, 22 refs. Correction . Ibid., 49(1):220, Jan. 1961.

Table. DLC--This paper summarizes recent measurements of the attenuation of

radio waves by atmospheric gases and compares the measured losses with those

predicted by Van Vleck. Reasonably good agreement had been noted between the

predicted and measured losses for oxygen, but the measured loss for water vapor

is considerably in excess of that predicted. Various factors which may influence

this discrepancy are discussed. --Authors' abstract.

E-776 Takahira, Akira and Irie, Hiromi, Characteristics of maritime advective duct and

their effect on the micro wave propagation beyond the line of sight . Japan. Radio

Research Laboratories, Tokyo, Review, 6(22):3-ll, Jan. 1960. 12 figs. , table,

6 refs. In Japanese; English summary p. 3. DLC. Also in Japan. Radio Research

Laboratories, Journal, 7(33): 531-544, Sept. 1960. 12 figs. , 8 refs. , 8 eqs. DBS--

In order to study the microwave propagation over the sea beyond the line of sight,

a comprehensive survey of the maritime meteorology has been carried out on the

Sea of Kashima by means of a helicopter. The experimental results of the vertical

distribution of atmospheric refractive indexes over the Sea of Kashima are summarized. The development of space distribution of maritime advective ducts is discussed in detail introducing the eddy diffusion equation. A general procedure to "predict" the map and profile of M curve over the sea up to 20 km from the coastline is described too. It is shown that the "predicted" map agrees well with the

observational results. (Met. Abs. 13. 12-56) --Authors' abstract.

E-777 Takahira, Akira; Irie, Hiromi and Nakamura, Takuma, Observational results of

VHF, UHF and SHF propagation beyond the radio horizon. Japan. Radio Research

Laboratories, Tokyo, Journal, 17(31): 197-211, May 1960. 13 figs. , 3 tables, 9

refs. , 6 eqs. DLC. Also Japanese version in their Review, 6(24): 146-154, May

1960. --Overland radio propagation tests were conducted at the distance of 125 km

beyond the radio horizon in the Kanto plain in Nov. and Dec. 1957, and July, Aug. , and Sept. 1958. The frequency bands were VHF 150 Mc/s, UHF 600 Mc/s, and

SHF 3 Gc/s and 10 Gc/s. From the observational results the following conclusions were obtained: In the daytime the reflected waves from the elevated layer were

superposed on the diffracted waves in VHF band, but in UHF band the reflected

waves from the elevated layer were predominant, and in SHF band the scattered

waves predominated, while at night the reflected waves from the elevated layer were predominant in all bands. (Met. Abs. 14. 4-120) --Authors' abstract.

E-778 Tao^Kazuhiko and Hirao, Kunio, Vertical distribution of radio refractive index in

the medium height of atmosphere . Japan. Radio Research Laboratories, Journal,

7(30):85-93, March 1960. 5 figs. , 3 tables, 2 refs. DBS--The mean vertical distribution of the refractive index is studied by the use of various kinds of data.

Though the distribution in the lower part of the atmosphere agrees well with the

form of an exponential curve, the upper part is not to be expressed by the extra- polation of this formula. Further, a new method available for the check of stability of the mean distribution curve is introduced with some examples of application

to data obtained in Japan. --Authors' abstract.
195

E-779 Tatarskii, V.I. , Radiofizicheskie metody izucheniia atmosfemoi turbulentnosti.

(Radiophysical methods of the study of atmospheric turbulence.) U.S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii', Radiofizika, 3(4):551-583, 1960. 22 figs. , 48 refs. , 57 eqs. DLC--This is an analytical

review (based on Russian and foreign literature) of results achieved so far in the

study of atmospheric turbulence by means of radio propagation experiments, and in

comparison of results of such studies with direct measurements of turbulence. The

problems considered in particular are: 1) characteristics of atmospheric turbulence,

2) scattering of radio waves in a turbulent atmosphere; phase and amplitude fluctuation, 3) experiments in the atmospheric layer near the ground, 4) tropospheric re- fractive index fluctuations and 5) turbulence in the ionospheric E layer. The last

two points are treated in considerable detail. --G.T.

E-780 Thompson, Moody C. , Jr. ; Janes, H. B. and Kirkpatrick, A. W. (all, Nat'l.Bur. of

Standards, Boulder, Colo.), An analysis of time variations in tropospheric refractive index and apparent radio path length. Journal of Geophysical Research, Wash.,

D.C., 65(1): 193-201, Jan. 1960. 15 figs. , 8 refs. DWB, DLC -The National Bu- reau of Standards has been conducting a series of measurements for a study of the

characteristics of the turbulent lower atmosphere and its effect on the accuracy of

radio direction finding, guidance, and geodetic measurement systems. The results

of three experiments are presented, one consisting of recordings of refractive index

and apparent path length variations at 9400 Mc/s over a 15. 5 mi path on Maui,

Hawaii and the other two consisting of similar measurements made over a 9. 5 mi

path near Boulder, Colo. The correlation of refractive index and apparent path

length fluctuations is discussed as well as the power (variance) density spectra

of both variables. (Met. Abs. 12. 3-97) -Authors' abstract.

E-781 Thompson, Owen (General Electric Co.), Microwave propagation . Wire and Radio

Communications, Ridgewood, N. J. , 78(4):13-15, 48-49, April 1960. 2 figs. , table,

eqs. DWB--The basic elements of radio wave propagation and the effect of many

vagaries of atmospheric change on the system's reliability are discussed. The discussion includes path clearance, atmospheric refractive index, space and frequency

diversity, parabolic antennas, and passive reflectors. (Met. Abs. 13. 5-129) --O. T.

E-782 Toman, Kurt (GRD, AF. Camb. Res. Center), Focusing, defocusinq and refraction

in a circularly stratified atmosphere. U.S. National Bureau of Standards, Journal

of Research, Sec. D, 64(3): 287-288, May/June 1960. 2 figs. , 3 refs. DWB.DLCFocusing, defocusing, astronomical refraction and path length of rays as a function

of the departure angle <£* of the ray at the source is described for cases with the source outside, inside, or on the boundary of a circular stratification. Relative to zero elevation angle symmetrical and centrosymmetrical distributions are found.

(Met. Abs. 14. 2-124) -Author's abstract.

E-783 Troitskix, V. N. , Rasprostranenie santimetrovvkh voln na qornykh trassakh bol'sho?

protiazhennosti. (The propagation of centimeter wave over long distance mountain

paths.) Radiotekhnika i Elektronika, Moscow, 5(12): 1919-1924, Dec. 1960. 9

figs. , ref. Tfansl. into English in Radio Engineering and Electronics, N. Y. , 5(12):

61-69, 1960. DLC —This article is concerned with the fading of cm and dcm waves

on long distance mountain routes. Experimental data on the fading on three mountain routes in Central Asia are given. Conclusions are made concerning the nature

of the fading on mountain routes using the long distance tropospheric propagation

of ultrashort waves. --Author's abstract.
196

E-784 U.S. Navy Weather Research Facility, Meteorological aspects of radio-radar propa - gation. U.S. Office of Naval Operations, NAVWEPS 50-IP-550, June 1960. 173 p. Figs. , tables, 26 refs. --This publication is intended as a comprehensive reference

in radio-radar meteorology for Naval Weather Service personnel. The material is

presented in 4 parts. Pt. 1 deals with electromagnetic propagation and radio-radar

propagation. Pt. 2 is devoted to the atmospheric refractive index, to the standard

atmosphere, and to the actual atmosphere. Pt. 3 speaks of the computation of at- mospheric refractive effects on radio-radar performance, and Pt. 4 is devoted to the

meteorological studies of the atmospheric refractive index. (Met. Abs. 14B-126)

-M.B. G.

E-785 Voge, J. , Reflexions partielles dans 1' atmosphere et propagation a grande distance, IV, 'Reflexion speculaire et reflexion diffuse sur des feuillets atmospheriques. (Partial reflections in the atmosphere and long range propagation, Pt. 4,

Specular reflection and scattered reflection from atmospheric layers. ) Annales

des Telecommunications, Paris, 15(1/2) :33-47, Jan. /Feb. 1960. 7 figs. , 20 refs.,

eqs. DLC --After discussing the principles of existing theories (diffusion and partial reflections) on the propagation of ultrashort waves at great distance, the

author emphasizes the necessity to distinguish between the "space" and "time"

variables and to consider the instantaeous characteristics of the received signal.

They also discuss the data concerning the splitting up of the atmosphere and es- tablish formulas permitting to compute the power reflected on a layer with a regular surface, and with an irregular surface. The author hypothesizes that the irregularities of the surface of the layer may be due to atmospheric turbulence, showing

a connection between the phenomena of reflection and turbulence. The formulas

will be employed in a future paper to calculate the characteristics of the signal

strength. The author then gives an account of the results which lead him to distinguish between three types of propagation (specular reflection, diffused reflection, diffusion in an important volume of the atmosphere) with a possibility of

progressive transition from the one to the other when frequency increases. The 3

mechanisms may theoretically intervene simultaneously according to frequency,

with a progressive transition from the first to the latter when the wavelength is

lowered. (See refs. E-542, 628, 783, 772, 715. ) (Met. Abs. 12. 1-100)-A. V.

E-786 Voge, J. , Reflexions partielles dans 1 'atmosphere et propagation a grande distance. V. Reflexion et diffusion tropospherigue des ondes radioelectrigues.

(Partial reflections in the atmosphere and long distance propagation, Pt. 5, Tropospheric reflection and scattering of radioelectric waves.) Annales des Telecommunications, Paris, 15(5/6):107-121, May/June 1960. 9 figs. , 22 refs. DLC--

After pointing out in the introduction some of the most important results which he

proposes to discuss, the author determines, on the basis of formulas included in

the preceding article (Pt.4), the power received at the end of propagation paths

through specular and diffuse reflection on atmospheric tilts or on stretched layers

formed by a group of tilts. He next reviews the principal conclusions of the theoreticians of turbulent diffusion. This leads to a systematic comparison of the 3

mechanisms of long distance propagation of ultrashort waves. The author tries to specify the conditions and more especially the frequency bands for which one or another of the phenomena has a preponderant influence in the signal received; he

shows that, in most cases, the diffuse reflection is locally far more important

than the turbulent diffusion, while, on the other hand, the last concerns a larger

volume of the atmosphere. The various propagation mechanisms are also compared

from the point of view of the variations of fields in function of distance and fre- quency, and as regards the fine characteristics of the signal received: diversity

distances, width of transmission band, rapid fluctuations. The article ends with

a study of the "instantaneous" characteristics of the field received which, according to the author's opinion, very frequently gives evidence of the influence of discrete reflections on tilts, rather than turbulent diffusion phenomena. (See refs.

E-542, 328, 785, 772, 715. ) (Met. Abs. 13. 1-120)-A. V.
197

E-787 Voge, J. , Theories de la propagation troposph^rigue au-dela de l'horizon . (Theories on tropospheric transhorizon propagation.) Annales des Telecommunications, Paris,

15(ll/12):260-265, Nov. /Dec. 1960. 38 refs. DLC --The author limits his investigations to the so-called "transhorizon" or "through tropospheric diffusion" normal

propagation, excluding the superrefraction phenomena. In addition, a special in- vestigation is made of the works carried out since the latest ISRU General Assembly (Boulder 1957). This survey and restatement do not claim completeness, their

principal purpose is to emphasize a certain number of results and to present the

discussions they raised. The three main types of theories set forth to explain the

characteristics of the "transhorizon" propagation are successively examined: tur- bulent diffusion in the troposphere, partial reflections upon atmospheric discontinuity layers and model theories. (Met. Abs. 13. 5-130) --A.V.

E-788 Wade, H. D. and Fannin; B. M. , Wave propagation through a turbulent tropospheric

layer. Texas. Univ. Electrical Engineering Research Laboratory, Contract AF 19

(604)-5504, Report No. 6-34, May 30, 1960. 61 p. 5 figs. , 27 refs. , 132 eqs.

DWB--The analysis of wave propagation phenomena induced by homogeneous tropospheric layers is adequately accomplished through the use of conventional wave

theory (microwave optics). Propagation through homogeneous tropospheric turbulence can be handled theoretically by the use of a first Born approximation (single

scattering) approach in many cases. The choice of the proper theory to apply to the case of propagation through a tropospheric layer of anisotropic turbulence is

not clearly established. This report presents a preliminary analysis of wave propagation through such a layer. A comparison is made of single scattering and wave

theory analyses of wave propagation through a homogeneous non-turbulent tropospheric layer in order to gain insight into the' validity of single scatter theory for a limiting case. The single scattering approach is then applied to an assumed

mathematical model of an anisotropically turbulent tropospheric layer, and integral expressions are derived for the cross correlation functions of the amplitude

and phase, respectively, of a wave which has passed through the layer. A preliminary investigation of the possibility of using a thin, random, phase changing

screen as an approximation of the turbulent layer is reported. Conclusions drawn

from this research and recommendations for future research are given. (Met. Abs.

13. 8-140) -Authors' abstract.

E-789 Williamson, V.L.etal. , A summary of VHF and UHF tropospheric transmission on

loss data and their long term variability . U.S. National Bureau of Standards, Technical Note, No. 43, March 1960. 37+ p., 137 figs. , 4 tables, 2 refs. DLC--

Cumulative distributions of hourly median basic transmission loss are presented

for 135 beyond line-of-sight radio path in the U.S. In order to allow for seasonal

trends of transmission loss, the year is divided into a summer period, May through

Oct. , and a winter period, Nov. through April. The long term variability of observed hourly medians is compared with predicted variability based on empirical curves by Rice, Longley and Norton. --Author's abstract.

E-790 Willson, F. E. and Runge, W. A. , Data transmission tests on tropospheric beyond

the horizon radio systems. IRE Transactions on Communications Systems, N. Y. , 8(l):40-43, March 1960. 7 figs. , 3 refs. DLC -Results of data transmission tests

made on both single link and multi link tropospheric beyond the horizon systems

are presented. Tests were made at 750 or 1300 bits per sec, employing both double

sideband AM and FM methods of data modulation. In the single link tests the data

performance was determined for various transmission parameters such as median

channel noise, peak channel noise, radio received carrier level, and order of diversity. Data were satisfactorily transmitted on a 2400 mi circuit consisting of nine

different beyond the horizon paths and 6 line of sight paths. The FM data modulation was notably superior to the AM type. --Authors' abstract.
198

E-791 Zlotykamin, C. , Realisations de klystrons de puissance a large bande . (Development of wide band power klystrons. ) Acta Electronica, Paris, 4(l):47-57, Jan. 1960. 8 figs. , 16 eqs. DLC--Many telecommunication units intended for tropospheric scatter propagation require the use of klystrons operating with a high gain

and a wide frequency band. The conditions which must be met if such features

are to be obtained are examined. The author then considers the influence of electrical and geometrical parameters on both gain and bandwidth. Some features leading to a reduction of the losses encountered in the transmission of the electron

beam are indicated. An electron gun is described. Finally, some examples of

klystrons actually developed are given to illustrate the principles set forth.

-R.M.

E-792 Zverev, V.A. , Rasseianie modulirovannykh voln na sluchamykh neodnorodnostiiakh. (Scattering of modulated waves by random inhomogeneities. ) U.S.S. R.

Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii,

Radiofizika, 3(5):903-904, 1960. Ref. , 12 eqs. DLC -It is shown that an analysis of the propagation of modulated waves makes it possible to determine the degree of correlation of fluctuations of waves at different frequencies and provides

information on the magnitude of the scattering volume and its form, data that are important in the experimental solution of the problem of the occurrence of a scattered field. --R.M.

1961

E-793 Abraham, L. G. , Jr. and Bradshaw, J. A. , Weather and reception level on a troposphere link: annual and short term correlations. U. S. Nat'l. Bureau of Standards,

Journal of Research, Sec. D, 65(2): 155-156, March/April 1961. 2 figs. , 13 refs.

DWB, DLC--The weather parameters suggested by the Booker-Gordon theory are correlated with data from a troposphere link not previously reported. While the

correlations over the whole year's weather cycle are high, the short term correlations practically vanish. The former without the latter lend little support to this

theory. (Met. Abs. 13. 4-99) -Authors' abstract.

E-794 Aksenov, V.I. , Utilization of Kirchhoff's approximation in the problem of the

scattering of radio waves by periodically rough surfaces with finite conductivity. Radio Engineering and Electronic Physics, N. Y. , No. 3:307-314, 1961. 2 figs.,

2 tables, 4 refs. , 20 eqs. Transl. of original Russian in Radiotekhnika i Elektronika, Moscow, 6(3):347-354, March 1961. DLC--On the basis of the HuygensKirchhoff principle and of approximations from geometrical optics, solutions to the problem of the scattering of radio waves by a limited region of double sinusoidal (undulation in two dimensions), and sawtooth surfaces with finite conductivity

are obtained. These solutions can be used in the analysis of the scattered field

in the far zone. The solution for a sawtooth surface is obtained in a finite form;

for a double sinusoidal surface, it is the form of a rapidly converging series.

Examples of the analysis of the scattering of waves by the indicated surface are examined. --Author's abstract.

E-795 Armand, N. A. and Vvedenskii, B.A. , Allowance for antenna directivity pattern

in the calculation of radio wave diffraction around the Earth. Radio Engineering

and Electronic Physics, N. Y. , No. 8:1083-1090, 1961. Table, 13 refs. , 38 eqs.

Transl. of original Russian in Radiotekhnika i Elektronika, Moscow, 6(8):1219-

1227, Aug. 1961. DLC —The diffraction field of a directional antenna with its

plane normal to the Earth's surface is investigated. It is shown that the directional
199

properties of a low lying antenna can be accounted for in the calculation of the

diffraction field by multiplying the dipole field equations by the antenna directive

gain. In the case of a high lying antenna the diffraction field is determined by the

part of the energy flux radiated from the antenna in the horizontal direction.

--Authors' abstract.

Armand, N. A. ; Vvedenskii, B. A. ; Kalinin, A. Let al. , Long range tropospheric

propagation of ultrashort waves (survey) . Radio Engineering and Electronic Physics,

N. Y. , No. 6:775-791, 1961. 9 figs. , 119 refs. , 2 eqs. Transl. of original Russian in Radiotekhnika i Elektronika, Moscow, 6(6):867-885, June 1961. DLC--An

analysis of experimental and theoretical work on long range tropospheric propagation of ultrashort waves is given. The field intensity is examined as a function of

distance, wavelength and time. The gain losses of antennas, the distortion of the

signal, and the band of transmitted frequencies are all analyzed. Various theories

describing the mechanism of long range tropospheric propagation of radio waves are considered. On the basis of the comparison with experimental data, it is shown

that none of the existing theories can completely explain all the available experimental results. --Authors' abstract.

Barghausen, A. F. and Peterson, C.F. , Path loss measurements vs prediction for long distance tropospheric scatter circuits . IRE Transactions on Communications

Systems, N. Y. , 9(4): 439-445, Dec. 1961. 9 figs. , table, 9 refs. , 7 eqs. DLC--

Before any communications circuit can be established between two points, whether

it be by wire lines, or by tropospheric or ionospheric radio propagation, a thorough

knowledge of the intended path should be obtained so that an efficient and economical installation can be made. Each system should have as high a reliability as is required for its intended use. Tropospheric forward scatter circuits have established their place in the worldwide communication network of the military and it is

the intent of this paper to illustrate by a specific example how the performance of a circuit of this type may be predicted with adequate accuracy without making

costly transmission loss measurements over the intended path. --Authors' abstract.

Barsis, A. P. and Johnson, Mary Ellen, Prolonged space wave fadeouts in tropospheric propagation . U.S. National Bureau of Standards, Technical Note, No. 88,

Feb. 8, 1961. 40 p. 30 figs. , 14 tables, 10 refs. , 2 eqs. DWB (M(055) U585te)

--This paper contains the results of studies performed during the last several years on the short term variability of tropospheric signals received over within-the-hori- zon paths. Signal variations of this type have been termed "prolonged space-wave

fadeouts", as they are mainly characterized by reductions in signal level to many

decibels below presumably constant values determined from geometrical optics

methods. The data described here were obtained from measurements over propagation paths in the Pacific Coast region of Southern California, and the continental

region of Eastern Colorado. Fadeouts are analyzed as a function of carrier fre- quency, path characteristics, and meteorological parameters. The study also includes an evaluation of fadeouts observed over a path using a mountain peak as a diffracting knife edge like obstacle between transmitter and receiver. (Met. Abs.

13. 1-341) -Authors' abstract.

Barsis, A. P. and Kirby, R.S. (both, Central Radio Propagation Lab. , Nat'l.Bur.

of Stds. , Boulder, Colo.), VHF and UHF signal characteristics observed on a long

knife edge diffraction path. U.S. National Bureau of Standards, Journal of Research,

Sec. D, 65(5) -.437-448, Sept. /Oct. 1961. 16 figs. , 9 tables, 16 refs. Also in

IRE International Convention Record, N. Y. , Pt. 1:17-34, 1961. DWB, DLC--
200

During 1959 and 1960, long term transmission loss measurements were performed

over a 223 km path in eastern Colorado using frequencies of 100 and 751 Mc/s.

This path intersects Pikes Peak which forms a knife edge type obstacle visible

from both terminals. The transmission loss measurements have been analyzed in

terms of diurnal and seasonal variations in hourly medians and in instantaneous

levels. As expected, results show that the long term fading range is substantially less than expected for tropospheric scatter paths of comparable length.

Transmission loss levels were in general agreement with predicted knife edge diffraction propagation when allowance is made for rounding of the knife edge. A

technique for estimating long term fading ranges is presented and the results are

in good agreement with observations. Short term variations in some cases re- semble the space wave fadeouts commonly observed on within-the-horizon paths,

although other phenomena may contribute to the fading. Since the foreground

terrain was rough, there was no evidence of direct and ground reflected lobe

structure. In most cases comparatively high correlation exists between signals

received simultaneously on two antennas with 8. 3 and 14 m vertical separation.

These separations were chosen as being representative for practical space diversity systems designed for eliminating the effects of fading arising from direct and

ground reflected phase interference phenomena. The comparatively high correlation observed suggests that space diversity will be relatively less successful in

mountain obstacle paths with rough terrain near the terminals than on tropospheric

scatter paths or on line-of-sight paths over smooth terrain. The enhancement of

field strength associated with propagation over mountain ridges may cause con- cern in applications where mountains are being counted on to shield unwanted

radio waves. Some radio astronomy installations have been located in mountain

valleys for this reason, and it is possible that obstacle gain effects may aggravate rather than alleviate interference. (Met. Abs. 13. 6-92) --Authors' abstract.

E-800 Barsis, A. P.; Norton, K.A. ; Rice, P.L.and Elder, P.H. , Performance predictions for single tropospheric communication links and for several links in tandem.

U.S. National Bureau of Standards, Technical Note, No. 102, Aug. 1961. 154 p. 22+ figs., bibliog. p. 151-154, eqs. throughout. DLC- -Performance of long distance tropospheric communication circuits, either singly or in tandem, is predicted in terms of the probability of obtaining a specified grade of service or better for various percentages of time. The grade of service is determined by the

minimum acceptable ration of hourly median predetection RMS signal to RMS noise

for the type of intelligence to be transmitted. The standard deviation of prediction

errors depends upon the percentage of hours the specified grade of service is re- quired and on parameters characterizing the propagation path. The possibility of

reducing this standard deviation by making path loss measurements is discussed.

It is shown that no improvement is possible unless the test path is very nearly

the same as the proposed operational path; in particular, unless the test path

and operational path have terminals less than one mile apart it is shown to be

doubtful in most cases whether the observations will be useful in improving the

reliability of the predicted performance of the proposed system. Assuming that

the test path and proposed operational paths are identical, estimates are given

of the number of days of observations required to halve the prediction uncertainty

or, alternatively, to reduce it to 3 db; in some cases several years of observations are required. A tutorial discussion is given in Appendix III of the concepts

of the effective noise figure and the effective input noise temperature of a receiving system. --Authors' abstract.
201

Bass, F. G. , Rasprostranenie radiovoln nad statisticheski neodnorodnc>y poverkhnost'iu . (Radio wave propagation over a statistically inhomogeneous surface.)

U. S.S. R. Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia

Vysshikh Uchebnykh Zavedenii, Radiofizika, 4(3):476-483, 1961. 5 refs. , 32 eqs.

English summary p. 483. DLC--By means of boundary conditions obtained in a previous paper (see E- , an examination is made of radio wave propagation over a random irregular surface. Reflection coefficients and attenuation function are obtained for the average field propagated over such a surface. --Author's abstract.

Bauer, Louis H. , Correlation of wind shear with tropospheric scatter signals . IRE Transactions on Antennas and Propagation, N. Y. , 9(5):466-470, Sept. 1961.

6 figs. , 11 refs. , eqs. DLC --Discusses the result of experimental data obtained

by AF Cambridge Research Center over East-West 400 mi path from Bedford to Wilson, N. Y. Correlation of the 10 - 90% fading range of the 915 Mc scatter re- cords with wind shear gave coefficients of 0. 76 to 0. 8 at a point 70 mi from the

common volume. Fading range increased by 1.4 db/m/sec/km. --W. N.

Bean, B. R. , Comparison of observed tropospheric refraction with values computed

from the surface refractivity. IRE Transactions on Antennas and Propagation, N. Y.,

9(4):415-416, July 1961. Fig. , 7 refs. , 3 eqs. DLC -Radar elevation angle observed in the Tularosa Basin of New Mexico are compared with values predicted

from the surface value of the radio refractive index. Although this method of prediction is not particularly efficacious under the conditions of this experiment en- couraging agreement nevertheless was obtained between predicted and observed:

a) mean value of elevation angle error, b) variation of elevation angle error with

Ns, and c) the degree of reduction in the uncertainty of prediction gained over the use of a single standard atmosphere. --Author's abstract.

Bean, B. R. (CRPL, Nat'l. Bur. of Stds. .Boulder, Colo.), Concerning the bi-exponential nature of the tropospheric radio refractive index. BeitrSge zur Physik der

Atmosphere, Frankfurt a. M. , 34(1/2):81-91, 1961. 9 figs. , 2 tables, 16 refs. , 9 eqs. German, English and French summaries p. 81-82. DWB, DLC--This paper

is concerned with examining the model N = (n-1) 10° = D exp -z/Hj + WQ exp

-z/Hw for the height, z, variation of the radio refractive index, n, within the

troposphere. The first term, D, is the component of the refractive index due to oxygen and the second term, W, is the water vapor component. The scale heights,

Hdand Hw > are sensitive indicators of climatic differences and maps of each are given for the U.S. for both summer and winter. The bi-exponential model yields more accurate estimates of N structure in the troposphere than the earlier single

exponential model and consequently gives more reliable estimates of refraction

for initial elevation angles in excess of 3 degrees but only a negligible improvement for the near zero angles of departure commonly used in tropospheric propagation. (Met. Abs. 13. 6-495) -Author's abstract.

Bean, B. R. and Cahoon, B.A. , Correlation of monthly median transmission loss

and refractive index profile characteristics. U.S. National Bureau of Standards,

Journal of Research, Sec. D, Wash. ,D.C. , 65(l):67-74, Jan. /Feb. 1961. 5 figs.,

5 tables, 20 refs. , 17 eqs. DWB, DLC --The difference in the monthly mean values

of the refractive index at ground level and at one kilometer above the ground level

is often used for the purpose of predicting the annual cycle of radio transmission

loss. The present study investigates the possibility of utilizing differences to heights other than one kilometer. A comparison of 100 megacycles per second

transmission loss recorded over 21 paths with various refractivity differences from

the surface to 3 km reveals that the surface value of the refractive index yields as
202

good a correlation as any of the refractive index differences due to the high correlation between the surface values and these differences; therefore, the more accessible surface value can be effectively substituted for the differences. Specifying

the refractive index profile at two or three additive points and using multiple correlation techniques does not significantly increase the correlation. The use of radio

data over the same path does not significantly improve the correlation over that obtained from only meteorological data, indicating the very practical result that inexpensive meteorological data may be used to predict the seasonal trend of VHF radio

field strengths with as much accuracy as expensive radio path measurements.

(Met. Abs. 13. 5-123) -Authors' abstract.

E-806 Bean, B. R. and Dutton, E. J. , Concerning radiosondes, lag constants, and radio

refractive index profiles . Journal of Geophysical Research, Wash. ,D.C. , 66(11):

3717-3722, Nov. 1961. 2 figs. , table, 11 refs. , 15 eqs. DWB, DLC -Temperature

and relative humidity reported by the radiosonde have long been converted to radio

refractive index without regard to sensor time lag. Past studies of radio ducting

incidence have shown that under restricted conditions only corrections for humidity sensor lag need be made. It is here shown that lag constants currently in the lit- erature are inadequate under conditions of superrefraction of radio waves. Use of

currently available lag constants indicates that, should any correction be made,

both temperature and humidity sensor lags must be considered for any climatological comparison of ducting incidence. By ignoring sensor time lag, one tends to underestimate ducting incidence; by correcting only for humidity sensor lag, one

tends to overestimate ducting incidence. (Met. Abs. 13. 8-143) --Authors' abstract.

E-807 Bean, B. R.and Horn, J. D. , Concerning the potential refractive index and the

molecular refractivity. Journal of Meteorology, Boston, 18(3): 427-429, June 1961.

10 refs. , 6 eqs. Comment by K.H. Jehn, p. 428-429. DWB, DLC--The authors consider K.H. JEHN's suggestion that the concept of the potential refractive index and

its application to synoptic scale weather analysis is more fundamental, and that

the approach of BEAN and HORN is essentially empirical. This note purports to clarify the differences between the two approaches. The advantages of the use of

molecular refractivity are explained, which has the advantage of allowing the recovery of the refractive index at a point solely from a knowledge of the altitude of the

point while, on the other hand, one cannot recover the refractive index at a point

from the potential refractive index without further information about the actual values

of temperature and vapor pressure. The A unit (referred to in the authors' previous

paper) has advantages for radio meteorological analysis over (Katz's potential re- fractive modula) (or K the potential refractive index), since it introduces the meteorological effects of heights upon the refractive index in a much simpler way, gives a

direct quantitative measure of radio refraction anomalies without further calculation

and, in addition, may be easily utilized as a synoptic tool. K.H. JEHN elaborates on his previous comments. (Met. Abs. 14. 7-108) --E. Z.S.

E-808 Bean, B. R.and Horn, J. D. , On the average atmospheric radio refractive index

structure over North America. Beitrage zur Physik der Atmosphare, Frankfurt a. M. , 34(1/2) :92-104, 1961. 20 figs. , table, 15 refs. , 3 eqs. German, English and

French summaries p. 92. DWB, DLC--The variation of the radio refractive index in

the first 3 km over North America is found to delineate the gross climatic features

of both surface and upper air conditions, particularly with respect to humidity content. Maritime climates are characterized by low mean values as well as small

seasonal and diurnal variations, while continental climates have larger mean values

as well as larger seasonal and diurnal ranges. Extensive charts illustrate these conclusions. Further, continental cross sections of vertical refractive index structure

are presented for the first time. (Met. Abs. 13. 6-93) --Authors' abstract.
203

E-809 Benoliel, Land Potts, J.B. , Interdependence between hourly median transmission

loss and surface refractivity index observed at 900 Mc on a 232 mile far beyond the

horizon path. IRE Transactions on Communications Systems, N. Y. , 9(4):445-450,

Dec. 1961. 5 figs. , 5 tables, 12 refs. DLC--A detailed analysis is made of propagation data obtained from the North Atlantic Scatter System installed in Iceland. In particular, the correlation of the transmission loss and meteorological observations on a long path is analyzed in detail. By separating the data into various time periods, it is shown that for periods of time during which the received field is lowest,

the correlation between transmission loss and surface refractivity is very high. The

ability to establish a strong correlation between transmission loss and surface re- fractivity for this period allows the system designer to make more accurate predictions of the lower expected received fields and thus is able to calculate the minimum required transmitter with greater accuracy. --Authors' abstract.

E-S10 Bowhill, S.A. (Penn. State Univ. ), The scattering of radio waves by an extended

randomly refracting medium. Journal of Atmospheric and Terrestrial Physics, London,

20(1):9-18, Feb. 1961. 2 figs. , 11 refs. , 19 eqs. DLC--A continuous medium containing 3 dimensional random inhomogeneities of refractive index scatters an electromagnetic wave which is incident upon it. This paper derives the form of the

emerging angular power spectrum of the wave, for the case where the scales of the

inhomogeneities are different in the 3 spaced directions. It is shown that the me- dium cannot be analyzed as a series of superposed thin phase screens, spaced in

the propagation direction, and with independent phase profiles. When a limiting

process is carried out, allowing for an arbitrary spatial correlation function for the

inhomogeneities in the 3 directions, a quite different result is obtained. This disparity is due to diffractive changes in the wave in passing from one inhomogeneity

to the next. (Met. Abs. 14. 3-157) --Author's abstract.

E-811 Braude, S.Ia. ; Ostrovskii, I. E. and Sanin, F.S. , Ispol'zovanie poniatia otritsatel' - nogo ekvivalentnogo radiusa Zemli dlia otsenki intensivno'i refraktsii radiovoln. (Use

of the concept of negative equivalent Earth radius for estimating strong refraction of

radio waves. ) U.S. S. R. Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 4(l):67-73, 1961.

4 figs. , table, 5 refs. , 15 eqs. DLC--The concept of the negative equivalent Earth's

radius is introduced in the well known rays alignment method to be applied to the case of the positive refraction: dn/dh -1, 57. 10"'m"^ (n being the refractive index,

h - height above Earth's surface). The Earth's sfericity is taken into account and

Frenels formulas are used for the field calculations. The problem comes to plane

boundary one by the introduction of the corresponding reduced heights. Formulas

and curves are given for the heights of the interference maximums versus the values

of the negative equivalent radius at the given distance from the source of radiation.

All calculations are carried out with the assumption that there exists a constant gradient of the refractive index in a sufficiently thick atmospheric layer. --Authors' abstract.

E-812 Byatt, W. J. and DeVault, G.P. (both, Sandia Lab. , Albuquerque, N.Mexico), An

iteration variation method for wave propagation problems. Journal of Geophysical

Research, Wash. , D.C., 66(6): 1793-1797, June 1961. Fig., 3 refs. , 32 eqs. DLC

--In a medium in which the index of refraction varies in one space coordinate only,

transform methods are convenient for reducing an inhomogeneous scalar wave equation to an ordinary differential equation in which the square of the space dependent

index of refraction appears explicitly. An iteration variation method for obtaining

approximate expressions for the dispersion relations within the medium is discussed. The ordinary differential equation is converted to an integral equation, the
204

solution of which is begun by iteration. The individual terms in the series thereby

formed, which we shall call iterates, then form the basis of a trial function for use

in a variational principle. The method is illustrated by an example. (Met. Abs.

14. 5-130) --Authors' abstract.

E-813 Casini, G. and Fagiolio, Atmospheric dispersion and absorption of microwaves.

Italy. Centro di Studio per la Fisica delle Microonde, Florence, Contract AF 61

(052)-437, Final Report, Sept. 1961. 63 p. Figs. , tables, refs. , eqs. (CFCRL62-136) DWB (M(051)188fi)--The experimental results of measuring the refractive

index of nitrogen, oxygen and argon discussed here, were obtained with a refractometer and with addition of some devices subsequently added for improved perform- ance. The techniques for increase of the signal-to-noise ratio of a crystal amplifier detecting system and to permit the realization of cavities having a very high

0(3. lO"3

) and a single resonant mode are described. The results are given in

tables and graphs. (Met. Abs. 14. 9-164) --Authors' abstract.

E-814 Cassedy, E.S.and Fainberg, J., Comments on Scatter communications with radar

chaff. IRE Transactions on Antennas and Propagation, N. Y. , 9(5):497-498, Sept.

1961. 15 refs. DLC--The authors point out that pertinent references were missing

in the above cited paper by R. A.HESSEMER (see E-831). These references "should

be made in order to verify (or refute) the formulas and data presented by Hessemer."

Hessemer replies that these references were included in an earlier paper (Univ. of

Arizona, Appl. Res. Lab. ,S -5. 80145, March 1959) and thus clears up the minor differences mentioned. --W. N.

E-815 Chisholm, J. H. ; Goodman, S.J. etal. , Frequency variations due to over-the-hori- zon tropospheric propagation . IRE Transactions on Antennas and Propagation, N. Y.,

9(4):384-389, July 1961. 11 figs. , 6 refs. , eqs. DLC -Discuss and present data

obtained by a well organized experimental UHF transmission over the 161 mi path

between Alpine, N.J. and Round Hill, Mass., using 388 Mc transmitted, returned

heterodyned to 416. 7 and retransmitted at 388. Detailed results are presented in

graphs and may be summarized as follows: For path lengths about 100 mi between

radio horizons, carrier frequency of about 400 Mc, the standard deviation of fre- quency fluctuations was approximately 0.6 cps, indicating transmissions feasible

at an accuracy of about 0. 15 parts in 10^. --W. N.

E-816 Clutts, C.E. ; Kennedy, R. N. and Tree ker, J. M. , Results of bandwidth tests on

the 185 mi Florida-Cuba tropospheric scatter radio system. IRE Transactions on Communications Systems, N. Y. , 9(4):434-439, Dec. 1961. 10 figs. , table, 4

refs. DLC --The first in a planned series of tests was conducted during March 1960, over the 185 mi FM system between Florida City, Fla. and Guanabo, Cuba. The

system was loaded with random noise of various bandwidth up to 2. 5 Mc, and peak

deviations up to + 8 Mc were used. Tests were made with no diversity and with

dual diversity. It was found that intermodulation, resulting from multipath propagation, can limit system performance. Both deviation and base bandwidth are important and have an influence on intermodulation and tone stability. Diversity has

little effect on intermodulation but improves tone stability appreciably. The paper

presents numerical results of the measurements of average intermodulation and

some information on cumulative probability distributions for various combinations

of base bandwidth, deviation, and diversity. --Authors' abstract.
205

Davids, H.H. , Thin route tropo - a new approach to long range communications.

IRE Transactions on Vehicular Communication, N. Y. , 10(2):28-35, Aug. 1961.

(Unchecked) --This new system of communications makes use of tropospheric scatter for the transmission of digital information over long distances more reliably

than high frequency radio, more economically than wire, less vulnerable than

microwave or VHF, and cheaper than conventional tropospheric scatter systems.

Using only a narrow bandwidth, it can be used for transmission of data (teletype,

telemetry, facsimile, etc.) over distances up to 500 mi, using relatively low

power transmitters and simple aerial systems. --Author's abstract.

de Jong, A. , Telecommunicatie door middel van troposferische verstrooiing ("tropo - spheric scatter"). (Telecommunication by means of tropospheric scatter. ) Electrotechnick, The Hague, 39(23): 581-593, Nov. 9, 1961. 26 figs. , 2 tables, 9 refs.

DLC --Results of measurements by the Dutch Post Office between April 1958 and

March 1960 over a 180 km North Sea path between Domburg and den Helder, two

points on the coast of Holland, are discussed. The received signal was continuously recorded by a double pen recorder; slow fading recordings (6 min time constant) were made and monthly cumulative time distribution curves are shown. The

link chosen can be regarded as comparable with a similar one with England, The

results agreed well with others obtained in various parts of the world and it is con- cluded that a North Sea link for telephony or, if need be, a television, is technically possible using tropospheric scatter. --Electr. Eng. Abs.

Dennis, Arnett S. , Performance of tropospheric scatter systems as a function of

weather conditions. Stanford Research Institute, Menlo Park, Calif. , Contract

DA-36-039 SC-85052, Final Technical Report 5, June 1961. 32 p. 5 figs. , 3

tables, 22 refs. , 25 eqs. DWB (M(051) S785fin) -Previous studies have shown

that signal levels on tropospheric scatter links are related to weather conditions

along the path. It has been found that monthly median signals are correlated with

radio refractivity gradients near the ground. Thus, climatological data can be

used to improve estimates of basic transmission loss for projected scatter links. In this paper the correlations of hourly median signals with refractivity gradients

and the surface refractivity are investigated for an over-water and a coastal path

and found to be significant. This indicates that short range forecasts of scatter

circuit performance over water and some coastal areas can be made using routinely

available meteorological data. The question of extending the STARCOM network

in the western Pacific using tropospheric scatter links is discussed briefly in the

light of these considerations. —Author's abstract.

Dixon, J.M. , Temporal variation of medium frequency ground wave field strength. Institution of Radio Engineers, Australia, Proceedings, 22(4) -.250-252, April 1961.

5 figs. , table, 5 refs. , 2 eqs. DLC-The results of medium frequency ground wave

field strength measurements are analyzed to show the temporal variation to be ex- pected under Australian conditions. Data of measurements made during 1953-56

are presented and compared with similar measurements made in Europe and North

America. The Australian results are found to be different from those obtained

elsewhere, since no common seasonal trend or correlation with temperature could

be ascertained. The variation in field strength at noon was small; in good conductivity soil the results show a trend toward more stable conditions with de- crease in frequency which corresponds to an increase in penetration. --G. T.
206

E-821 Dutton, E. J. , On the climatology of ground based radio ducts and associated fad - ing regions . U. S. National Bureau of Standards, Technical Note, No. 96, June 1961.

38 p. 51 figs. , 7 tables, 10 refs. , 30 eqs. DWB--This estimation of variation of occurrence of radio ducts with arctic, temperate, and tropical climate conditions

is based on a geometrical optics definition of the limiting case in which ray techniques may be used. This criterion is applied to 3-5 yrs of radiosonde observations. Maximum observed incidence of ducts was 13% for tropical, 10% for temperate and 5% for arctic locations. Mean initial elevation angle of radio ray trapping was about 3 mr, maximum 5. 8 mr. Steepest gradient of N observed was -420

N units/km. Observed ducts trap radio waves of frequency's 1 kMc at all locations for at least 50% of the time. --Author's abstract.

E-822 Dutton, E. J. and Thayer, G. D. , Techniques for computing refraction of radio waves

in the troposphere. U. S. National Bureau of Standards, Technical Note, No. 97,

Oct. 17, 1961. 55 p. 8 figs. , 26 tables, 43 eqs. DWB (M (055) U585te) -Eight

methods of computing atmospheric refraction of radio rays are discussed with appropriate theoretical background. These methods are: 1) the high angle, or astronomical, refraction case; 2) the statistical method; 3) the low angle, or terrestrial,

refraction case (Schulkin's method); 4) the four-thirds Earth model; 5) the exponential model; 6) the initial gradient correction method; 7) the departures from

normal method; 8) a graphical method (Weisbrod's and Anderson's method). Sample

computations are included for each of the above methods. (Met. Abs. 13. 9-109)

—Authors' abstract.

E-823 Edinger, James G. and Hoi zworth, George C. , Attempts to detect inversions using

the AN/TPQ-6 radar. (In: Edinger, James G. , Variability of low level thermal stratification over coastal terrain in southern California. California. Univ. at L. A. Dept.

of Meteorology, Contract CWB-9666, (unnumbered report), May 1961. p. 15-28.

10 figs. , tables, 9 refs. ) DWB (M(051) C153v)--A vertically pointing radar, wavelength 0. 86 cm has been operated near the southern California coast by the U.S.

Weather Bureau for a number of months during the past two years. One of the purposes of this operation has been to examine the possibility of determining the

thermal and/or water vapor stratification of the lower atmosphere, in particular the

top surface of the marine layer, from angel activity. Angels were frequently observed through the lower few thousand feet and occasionally were highly concentrated in relatively narrow bands that persisted over several hours. From the radar

records, recorded by facsimile, attempts were made to relate angel activity to meteorological variables. In this connection U.S. Weather Bureau radiosonde observations at the radar site have been utilized. Generally, the relationships are consistent with the hypothesis that angels are the result of echoes from regions of

very high index of refraction gradient. Such gradients are believed to be produced

by elaborate deformation of initially simple strata that are characterized by some

lesser index of refraction gradient. Consequently, angel activity seems best re- lated to stirring in the atmosphere. --Authors' abstract.

E-824 Feinberg, E.L., Rasprostranenie radio voln vdol'zemnoi poverkhnosti. (Radio

wave propagation along the Earth's surface.) Moscow, Akademiia Nauk SSSR, 1961.

546 p. Numerous figs. , numerous eqs. Bibliog. p. 535-543. DLC (QC661.F4)--

This comprehensive monograph covers all aspects of the theory of surface (i. e. , nonionospheric) radio wave propagation, based on extensive study of world literature.

After setting out the basic equations of radio wave propagation, the author analyzes

the medium in which propagation takes place, propagation in homogeneous media,

refraction by a plane boundary, the field near a plane boundary, dipole near a plane

and a spherical earth, the field over an electrically inhomogeneous surface and
207

propagation over an irregular surface, through an inhomogeneous stratified medium

and through a turbulent troposphere. --G.T.

E-825 Filipp, N. D. , O kharaktere fluktuatsii radiosignala na ukv pri rasprostranenii nad

neodnorodnoi poverkhnost'iu. (Character of fluctuations of a UHF radio signal

propagating over an inhomogeneous surface.) Radiotekhnika i Elektronika, Moscow, 6(9) -.1432-1441, Sept. 1961. 6 figs. , 12 refs. , 19 eqs. Transl. into English

in Radio Engineering and Electronic Physics, N. Y. , No. 9:1270-1278, 1961. DLC

--Approximate expressions are obtained for the mean level of the radio signal and

its relative fluctuations at the output of a square law detector for propagation in an inhomogeneous medium over an irregular interface. The values of the normalized

functions of the spatial and temporal correlations of the fluctuations of the wave

field in the presence of an irregular interface are compared with the values of these

functions in free space. The deductions obtained are compared with experimental

data. --Transl. of author's abstract.

E-826 Foot, T.B.Lowell and Lucas, W. J. , Tropospheric scatter propagation. GEC, Journal

of Science and Technology, London, 28(3) -.126-138, 1961. 19 figs. DBS --Describes

a long term investigation started in 1955, into the characteristics of an unmodulated

tropospheric scatter signal in the band 3-10 Gc/s. A 3480 Mc/s link over a 173 mi

path was operated for 3 yrs, and for part of the time signals were also recorded at a point on the same line 247 mi from the transmitter. Later a link at 9640 Mc/s was

established over the same 173 mi path and operated simultaneously. Details are given of short and long term variation of median transmission loss, of correlation

between signals at the two receiving sites, of the distribution of rapid amplitude

fluctuations, and of fading characteristics at both operating frequencies. --Electr.

Engr. Abs.

E-827 Ghosh, S.N. and Malaviya, V. (both, J. K. Inst, of Applied Physics, Univ. of

Allahabad, India), Microwave absorption in the Earth's atmosphere. Journal of

Atmospheric and Terrestrial Physics, London, 21(4) -.243-256, July 1961. 9 figs. , 2 tables, 9 refs. , 12 eqs. DLC--In this paper the microwave absorption has been

calculated for different layers of the earth's atmosphere around peak resonance fre- quencies for each consitutent gas. The total absorption for the whole atmosphere

is then obtained. For such calculations, it is necessary to know the peak absorption at the center of the absorption line and its half width. It has been shown that

for atmospheric gases the peak absorption is pressure independent and that it var- ies as (3-x)., power of absolute temperature for diatomic (O^) and linear polyatomic

(NpO) molecules and as (7/2—x) , power of absolute temperature for symmetric

(H^O) and asymmetric top (CO molecules. The half widths of the absorption lines

have been calculated after assuming the temperature from ARDC Model Atmosphere

and the vertical distribution of atmospheric constituents as given by MILLER. Three

sets of curves are also presented whereby the amount of absorption at an operating

frequency can be calculated for different atmospheric layers. (Met. Abs. 13. 6-95)

--Authors' abstract.
208

E-828 Gray, R.E. , Tropospheric scatter propagation and meteorological conditions in the

Caribbean. IRE Transactions on Antennas and Propagation, N. Y. , 9(5):492-496,

Sept. 1961. 5 figs. , table, 13 refs. DLC--The UHF transmission loss beyond the

horizon in this region was found to be far less than over similar path lengths in temperate climates. The large gradient of the atmosphere refractive index prevalent in

the Caribbean may be responsible for the differences discussed comparatively.

-W. N.

E-829 Gusiatinskii, I. A., Iskazheniia pri peredache televideniia po troposfernym liniiam

sviazi s chastotnoi moduliatsiei . (Distortions in television transmission over

tropospheric FM links. ) Elektrosviaz", Moscow, 15(9):15-21, Sept. 1961. 4 figs.,

10 refs. , 26 eqs. Transl. into English in Telecommunications, N. Y. , No. 9:16-23,

Sept. 1961. DLC- -Frequency variations at the receiver input are determined for different transmitter frequencies on the basis of a trapezoidal law. The formula is

applicable to estimating distortion of TV signals in FM. --Transl. of author's abstract.

E-830 Hayre, H.S.and Moore, R.K. (both, El ec. Engrg. Dept. , Univ. of New Mexico,

Albuquerque) , Theoretical scattering coefficient for near vertical incidence from

contour maps. U. S. National Bureau of Standards, Journal of Research, Sec. D,

65(5):427-432, Sept. /Oct. 1961. 4 figs. , 2 tables, 21 refs. , 17 eqs. DWB.DLC--

In calculation of the theoretical scattering coefficient for a terrain, previous auth- ors tentatively assumed the normalized autocovariance function

-Ar

2

P{.r) = e for the ground elevation as a function of distance from a given point.

Recently autocorrelation studies were made using maps with contours ranging from one to twenty-five feet. These resulted in curves of/> (r), which are approximated

by exp( — |r|/B). The theoretical scattering cross section ( & ) of many such ter- rains can be expressed as

*0 = 4Y2-^4 ilnT e-4kVcOS2

fl f (4K2

<x 2

) n (COS2 A ) n + 1 ^

(n-l)!(2K2

B

2

sin

2 ^ + n2

) 3/2,

where & , A, k, and & are standard deviation of the target terrain, wavelength,

wave number (2^/7L) and the angle of incidence respectively. For the case where

1/B is small as compared to k, the above expression becomes

(J - 4<r2

^3 k0coCe)fo+ =5* 0°

These expressions, when normalized, are in agreement with experimental results of

other authors. It is also noteworthy that the results obtained with an acoustic

simulator model compared very well with this theoretical expression. This work is

based on the property that the ground is conducting and has random elevation variations. Theoretical results calculated on the basis of varying ground impedance

rather than its elevation are also in agreement with this expression. (Met. Abs.

14. 9-170) -Authors' abstract.
209

E-831 Hessemer, R.A. , Jr. , Scatter communications with radar chaff. IRE Transactions on Antennas and Propagation, N. Y. , 9(2):211-217, March 1961. 4 figs. , table,

9 refs. , 35 eqs. DLC--Attempts to establish moderate range communications between non-line of sight points using numerous metallic half-wave dipoles (chaff)

interspaced randomly as scattering agents. An analytical expression for the scat- tering cross section is sought in the first part of the paper, and the second part is devoted to a comparison of the reradiation loss and horizontal ensemble gain. The

results are presented in graphs and a table. (See ref. E-814)--W. N.

E-S32 Hirai, Masaichi, Diversity effects in spaced antenna reception of tropospheric

scatter waves. Japan. Radio Research Laboratories, Journal, 8(38/39): 301-329,

Sept. 1961. 7 figs. , 3 tables, 19 refs. , 154 eqs. DBS-Amplitude correlations

between signals received with spaced antennas in tropospheric scatter propagation

beyond the horizon are considered theoretically and it is shown that theoretical

values coincide fairly well with experimental data. A new general formula expressing the received signal strength in tropospheric scatter propagation is derived, taking the directivities of both transmitting and receiving antennas into consideration.

The correlation of angle diversity reception in tropospheric scatter propagation is

also discussed theoretically. --Author's abstract.

E-833 Hirai, Masaichi, Multipath properties of tropospheric propagation of very short

radio waves beyond the horizon. Japan. Radio Research Laboratories, Journal,

8(37): 147-170, May 1961. 11 figs. , 3 tables, 5 refs. , 91 eqs. DBS--This paper

contains theoretical considerations of mutual relations between the arrival angle

distribution of multipath waves, the space diversity characteristics, the beyond- the-horizon antenna beam pattern and the antenna-to-medium coupling loss in tropospheric propagation of very short radio waves beyond the horizon and illustrates

some numerical examples with experimental data. --Author's abstract.

E-834 Hirao, Kunio (Radio Res. Labs. ), Short range echoes of HF waves observed on the

Antarctic Research Expedition ship. Antarctic Record, Tokyo, No. 11:184-190,

Jan. 1961. 6 figs. , 3 refs. Japanese summary p. 184. DWB--Reports on the short

range echoes of HF waves observed during the Antarctic Research Expedition in

1956 and compares these with records made in 1958 and 1959. It is concluded that

good propagation conditions over the ocean cause the backscatter of HF waves, that

the backscatter "may be due to sea waves". Since the echoes show diurnal variations, daily changes may occur in the refraction and diffraction of radio waves or in

their reflection in the lower troposphere. It is also assumed that some aerosol

above the sea may affect the refractivity. This assumption is to be tested in the near future. (Met. Abs. 14. 11-113)»E. Z.S.

E-835 Johler, J. R. and Lilley, CM., Evaluation of convolution integrals occurring in the

theory of mixed path propagation. U.S. National Bureau of Standards, Technical

Note, No. 132, Oct. 15, 1961. 20 p. 4 figs. , 4 refs. , 39 eqs. DLC -The theory

of propagation of electromagnetic waves around a sphere treats the smooth homogeneous case, i. e. , the case in which the surface impedance of the sphere is in- terrupted by an abrupt change in conductivity such as a land/sea boundary. It is

known, however, that such theory can be extended to treat inhomogeneous, irregular terrain by formulating certain convolution integrals which utilize the smooth

homogeneous formulas. The evaluation of these integrals can be accomplished

with dispatch on a large scale electronic computer with the aid of numerical analy- ses techniques. The particular case of a land/sea boundary in a smooth, spherical

surface is illustrated for a variety of cases by evaluating the convolution integrals on a large scale computer. --Authors' abstract.
210

E-836 Kalinin, A.I. , Effect of earth in UHF tropospheric scatter propagation . Radio

Engineering and Electronic Physics, N. Y. , No. 5:640-644, May 1961. 2 figs. , 5 refs. , 27 eqs. Transl. of original Russian in Radiotekhnika i Elektronika,

Moscow, 6(5) -.725-727, May 1961. DLC, DBS--A solution is found for determining

the average magnitude of the field intensity in tropospheric scatter propagation of

UHF waves, based on the hypothesis of coherent scattering from inhomogeneities

of the troposphere, exponential variation of the permittivity of air with altitude

above the earth's surface and diffraction around the earth's surface. --Author's

abstract.

E-837 Kirby, Roberts.; Rice, P. L. and Maloney, L.J. , Characteristics of point-topoint tropospheric propagation and siting considerations . U.S. National Bureau of

Standards, Technical Note, No. 95, Oct. 19, 1961. 93+ 8 p. 29 figs. , 5 tables,

28 refs. , 32 eqs. Price $2. 50. DWB (M(055) U585te) -Instrumental, topographic,

atmospheric, extraterrestrial and man-made noise factors influencing the propagation of radiowaves through the troposphere are discussed in some detail, and ac- companied with useful graphs and tabular data. Means to improve radio communication and to countermeasure interferences are of particular interest to the communication engineers and system designers. Several experimental radio transmissions under a variety of conditions are referred to. Finally, some biological, as

well as other hazards of electromagnetic radiation, are discussed. Appendices

include useful conversion factors and constants, formulas, etc. --W. N.

E-838 Kitchen, F. A. ; Joy, W. R.R.and Richards, E.G., Some factors influencing 3 cm

radiowave propagation oversea within and beyond the radio horizon. Institution of

Electrical Engineers, London, Proceedings, Pt. B, 108(39): 257-263, May 1961. 9

figs. , table, 8 refs. DLC--The results of a number of short term oversea measure- ments of the variation of received signal level with range from a 10 Gc/s transmitter

are presented. It is shown that the variation of signal level within the horizon was

rarely that expected for propagation through an atmosphere having a uniform refractive index gradient. Signal losses of from 5 to 30 db frequently occurred well within

the horizon, these losses being recovered when the range between transmitter and

receiver was sufficiently reduced. A well defined interference pattern usually oc- curred in the region of reduced signal level. Some data on the variation of refractive index with height up to about 700 ft above sea level were gathered using a radio

sonde and a captive balloon, but the detail was not sufficiently fine to enable a dir- ect relationship to be established between signal losses within the horizon and the occurrence of irregularities in the refractive index profile at low elevations. A direct relationship was found to exist between the signal level within the horizon and

that propagated well beyond the horizon into the extra diffraction region. (Met.

Abs. 13. 12-55) -Authors' abstract.

E-839 La Grone, A.H. and Chapman, C. W. , Some propagation characteristics of high

UHF signals in the immediate vicinity of trees. IRE Transactions on Antennas and

Propagation, N. Y. , 9(5):487-491, Sept. 1961. 10 figs. , 8 refs. DLC -Report of

results obtained with 2880 Mc vertically polarized signals at several very low

angles. The effects of local vegetation determined and presented in graphs and

discussed. A brief pointing error signal analysis of a hypothetical direction finding system is included. —W. N.
211

Lane, J. A. (D. S. I. R. Radio Res. Station, Clough), The radio refractive index gradient over the British Isles. Journal of Atmospheric and Terrestrial Physics, London,

21(2/3): 157-166, June 1961. 6 figs. , table, 6 refs. , 4 eqs. DLC --Reference at- mospheres, specifying the average change of refractive index at radio frequencies

with height, are derived from basic meteorological data. The atmospheres are rep-

-V»V» resented by the equation N, = N . e , where N and N, are the average values

~ n s s n

of (n-1) 10 at the surface and at a height h, respectively, n being the refractive

index. This exponential relation is in agreement with the results of a series of

measurements with a microwave refractometer. The variations in N and b over the

s British Isles are relatively small in comparison with the changes observed in other areas (e.g. , over the United States); however, some local effects are evident

which are illustrated on maps of N , the average value of (n— 1) 10" at sea level. o A high correlation is found between N and AN (the average decrease in the first kilometer) but A N for a given N is slightly smaller for the region of the British s Isles than for the U.S. (Met. Abs. 13. 6-98) -Author's abstract.

McCollum, Robert (comp. ), Selected foreign references on scatter propagation of

ultrashort waves. 1956-1960. Wash. , D.C. , Science and Technology Div. , Library

of Congress, 1961. 87 p. 214 refs. with abstracts. DLC. Alphabetical by author,

with original title in parentheses. Translations indicated where known. "Comprises

material in three broad categories: theoretical investigation of the atmospheric scattering of ultrashort waves and closely related phenomena; practical applications and

equipment such as antennas and output tubes; and surveys of developments in scatter propagation research. Over half of the refs. cited are Russian. " --D. M. G.

Maenhout, A. G. (Roy. Met. Inst. , Belgium), Bijdrage tot de kennis van het brekingsindexklimaat-voor zeer korte radioqolven, over Belgie . (Contribution to the knowledge of the refractive index climatology for very short wavelengths over Belgium.

)

Vlaamse Academie voor Wetenschappen, Letteren en Scheme Kunsten van Belgie

Klasse der Wetenschappen, Mededelingen, 23(4), 1961. 25 p. 10 figs. , 6 tables,

13 refs. DLC --The atmospheric refractive index plays an important part in the study

of the tropospheric propagation of waves with short wave lengths and in their use to determine distances (radar, tellurometer) as well as in radio localizing (radiotheodolite, radio telescope, etc.). By means of radio soundings made at Uccle (Belgium)

during the last 6 yrs the author computed the refractive index of air for the electromagnetic waves with wavelengths between 5 m and 2 cm and determined average

variation of this index in terms of the altitude. For this purpose a refractive co- index has been defined by

N = (n-1) • 106

= ~f- + *\ • ?V

T

where N = co-index; n= refractive index; T= absolute air temperature; p = atmospheric pressure (in mb); pv - vapor pressure (in mb) and A = 77.6° K/mb and B=

4810° K. The average variation of the index with the altitude of Uccle is given by

the exponential law lnN=5. 79—0. 13 , This study also determines vertical gradient of the refractive index in lower layers and its value at the ground surface, as

well as the annual variation of these parameters and their mutual dependence. The

gradient of the refractive index shows an appreciable annual variation in the lower

kilometers of the atmosphere. The co-index presents an annual and a diurnal variation. A rough correlation is found between the value of the co-index at ground level

and the average index gradient in the air layer (surface —850 mb standard level).

The geometry of a tropospheric radio communication shows a yearly variation resulting from the annual variation of the refractive index. (Met. Abs. 14. 9-173) --A. V.
212

E-843 Maenhout, A. G. , L 'influence de l'oriqine de la masse d'air sur la propagation

tropospherigue des ondes metrigues . (Influence of air mass source on tropospheric

propagation of meter waves. ) Beitrage zur Physik der Atmosphere, Frankfurt a. M. , 34(1/2): 112-117, 1961. 3 figs. , 2 tables, 6 refs. German, English and French

summaries p. 112. DWB, DLC--The electromagnetic field, beyond the horizon, at 230 km of a radiotransmitter, with a wavelength of 3. 4 m, was measured. The measurements were analyzed in function of the air mass over the transmission path. We

found a correlation between the type of air mass and the measured median path loss

expressed in decibel referred to the value that would be expected for free space

transmission. We also noted that the diurnal variation of the radio field strength

is related to the type of air mass. The smallest path loss is observed in maritime

air of tropical origin and when maritime air lays above cold continental air (in

winter). In an unstable air mass the path loss is much higher. These experimental

results can be explained by the layer reflection theory. (Met. Abs. 13.6-99)

—Author's abstract.

E-844 Meadows, R. W. , Tropospheric scatter observations at 3480 Mc/s with aerials of

variable spacing. Institution of Electrical Engineers, London, Proceedings, Pt.B,

108(40): 349-360, July 1961. 16 figs. , 3 tables, 15 refs. DLC--Short term measure- ments are described of signal amplitude, fading characteristics, correlation distances and height gain at three ranges (130, 258, and 398 km) from a transmitting

system radiating horizontally polarized waves. Although the results were variable

and at times difficult to interpret, it is considered that 150 X should be an adequate horizontal spacing, even at the shortest ranges, for directional receiving

aerials operated in diversity, with a tendency toward smaller values for vertical

spacing. Fading rates lying generally between 1 and 10/sec are found, with Rayleigh type fading tending to occur at the longer ranges. No consistent relationship

between signal amplitude, fading and correlation distance is found, although the

highest fading rates are often accompanied by low correlation distances. Cross

correlation measurements show definite evidence of the steady drifting of scattering

centers. Diffraction effects leading to height gain are found, and there is some indication of standing waves due to ground reflections. Aerial siting is discussed

and the transportable equipment which was developed for the tests is briefly described. (Met. Abs. 13. 12-58) -Author's abstract.

E-845 Men', A.V. , Time (spectral) characteristics of phase difference fluctuations occurring in the propagation of radio waves in the troposphere. Radio Engineering and

Electronic Physics, N. Y. , No. 10:1451-1459, 1961. 6 figs. , 18 refs. , 4 eqs.

Transl. of original Russian in Radiotekhnika i Elektronika, Moscow, 6(10):1625-

1635, Oct. 1961. DLC --Average statistical characteristics of phase difference

fluctuations, obtained from experimental measurements over sea water, of fluctuations on a wavelength^ X = 10 cm and on a fixed path 33 km long, are given for a wide frequency interval. The data obtained pertain to the case of transverse cor- relation with different distances between receiving antennas (bases) b, ranging

from 2 to 100 m, corresponding to different ratios d/i^ 1(1 --characteristic cor- relation scale). The measurements were carried out in the illuminated region as

well as in the penumbral and shadow regions. --Author's abstract.

E-846 Misme, Pierre, Essais de radio climatologie dans le bassin du Congo. (Radio

climatology tests in the Congo Basin.) Annales des Telecommunications, Paris,

16(1/2) :28-40, Jan. /Feb. 1961. 16 figs. , 3 tables, 10 refs. DLC--In this article,

the refractive index, its gradient, the stability of the lower layers, and the water

vapor pressure at various altitudes are successively dealt with. The author investigates the variation with height, up to about 20 km, and the annual variation

of each parameter. Concerning atmospheric stability, he demonstrates that a
213

negligible error is made when the mean work developed to elevate a unity mass air

particle from one level to another is deduced from the mean monthly values. This

study further points out that the variations of the radio meteorological parameters

in altitude are correlated with surface precipitation intensity. The geographical zone to which the results obtained are applicable is delimited at the end of this

paper. (Met. Abs. 14. 3-16D--A. V.

Misme, P. (C.N. E.T.), L 'influence du gradient equivalent et de la stabilite at- mospherigue dans les liaisons transhorizon au Sahara et au Congo. (Effect of the

equivalent gradient and atmospheric stability on communications to a location beyond the horizon in Sahara and Congo.) Annales des Telecommunications, Paris,

16(5/6): 110-116, May/June 1961. 7 figs. , 2 tables, 7 refs. , 4 eqs. French sum- mary p. 110. DLC —Tests of radio transmission to a location beyond the horizon

have been carried out in the Sahara and the Congo for securing continuous radio

communication service. The study of transmission at 471 Mc at a distance of 160

km in the Sahara climate proved that classical radio meteorological parameters do

not explain a difference of 20 decibels in radio reception occurring in two different

months of the year. By applying theories of diffuse reflection, the role of atmospheric stability was found to be a major factor in radiowave propagation. The computed field variations compared well with those observed. A more generalized law

was derived, in which atmospheric stability plays a role equivalent to that of the

reflection gradient. The law was tested with satisfactory results in radio communications at 471 Mc at a 300 km distance in equatorial Africa. (Met. Abs.

13. 9-112) --S.N.

Nemirovskix, A.S., Shirina polosy propuskania pri odinarnom i raznesennom

prieme signalov dal'neqo troposfernogo rasprostraneniia ukv. (Useful bandwidth

of single and dispersed signal reception in distant tropospheric propagation of

USW.) Elektrosviaz', Moscow, 15(5):18-25, May 1961. 3 figs. , 7 refs. , 25 eqs.

Transl. into English in Telecommunications, N. Y. , No. 5:17-26, May 1961. DLC--

It is shown the useful band in tropospheric radio relay links become considerably

wider when, in addition to the scattered component, a regular diffracted component

is also received, or when reception of dispersed signals is achieved by means of

linear integration into an FM detector. --Transl. of author's abstract.

Northover, F.H. (Carleton Univ. , Ottawa), Effect of multiple atmospheric inversions on tropospheric radio propagation. Journal o£ Atmospheric and Terrestrial

Physics, London, 20(4) :295-296, April 1961. 3 refs. DLC. Also issued in U.S.

National Bureau of Standards, Journal of Research, Sec. D, 65(4): 385-392, July/

Aug. 1961. Fig., 6 refs. , 27 eqs. DWB, DLC --In " addition theorem", which

makes it possible to deduce the field under a system of multiple inversions from

the standard analysis given by the author in 1952 and 1955 for a single inversion,

has been discovered. The addition theorem is explained and the note is concluded

with the remark that there is one special case of the theorem in which the characteristic properties of the propagation can be clearly perceived. It occurs when the

layers are close together. The propagation is actually equivalent to that which

would be caused by a single inversion at the mean height having a dielectric discontinuity equal to the algebraic sum of the discontinuities of the separate inversions. A mechanism has been found which is capable of explaining the long distance fields without having to invoke the existence of a single strong elevated high

level inversion layer. (Met. Abs. 13. 1-116) --E. Z.S.
214

E-850 Norton, K. A. ; Herbstreit, J. W. et al. , An experimental study of phase variations

in line-of-sight microwave transmission. U.S. National Bureau of Standards,

Monograph No. 33, Nov. 1, 1961. 91 p. 74 figs. , 15 tables, 3 refs. DBS--During

1956 an experiment was conducted in Maui, Hawaii, to study the time variations

in the phase of arrival of microwave signals propagated over 15 mi path and the

time variations in the phase difference of signals. These time variations are analyzed in terms of their serial correlation functions and power density spectra tor different times of day. In some instances there was evidence of a diurnal cycle in

total variance of both phase and refractive index with larger variances during the

day time, but in other instances this diurnal effect was not detectable. The slope

of the phase spectra appeared to be independent of time of day or meteorological

conditions. The long term variations in single path phase were well correlated

with variations in the mean value of refractive index measured at 5 points along

the path. --Authors' abstract.

E-851 Ortwein, N. R. ; Hopkins, R.U.F.and Pohl, J.E. , Beyond-the-horizon overwater

microwave fields. U.S. Navy Electronics Lab. , San Diego, Calif. , NEL Report

1011, April 24, 1961. 149 p. Numerous figs. (incl. photos), 4 tables, 36 refs. , 40 eqs. DWB (M(055) U585r)--The purpose of this study was to gain detailed

knowledge of the physical causes of tropospheric scattering, determine and measure the characteristics, compare the practical results with existing theories in

order to optimize system designs. The methods used, including description of the

specific instrumentation, conclusions drawn, and the design equations obtained,

are contained in this report. The study was conducted in cooperation with the NEL

field station of the Univ. of Calif. , and covers the period Jan. 1, 1956 — May 1,

1960. (Met. Abs. 13. 9-114)-- W. N.

E-852 Ortwein, N. R. ; Hopkins, R. U.F. and Pohl, J.E. (all, U. S. Navy Electronics Lab.,

San Diego, Calif.), Properties of tropospheric scattered fields . Institute of Radio

Engineers, N. Y, , Proceedings, 49(4): 788-802, April 1961. 26 figs. , Stables,

30 foot-refs. DLC --Tropospheric scatter tests were performed in the Southern California region in conjunction with extensive meteorological measurements. The tur- bulent spectra were found to be, in the region of interest, proportional to k~5/3# In general, the scattered signals were found to agree with the turbulent single scattering model predicted by such a dielectric spectrum. Horizontal beamswinging ex- periments gave a dependence on the scattering angle of 0-14/3. A stronger dependence was observed for vertical beamswinging and is explained by a height dependence of the turbulent fluctuation spectra rather than anisotropy. This explanation is further supported by agreement with Booker and deBettencourt aperture-tomedium coupling loss. A J\ -1/3 wavelength dependence was observed under standard atmospheric conditions. In the presence of weak turbulent layers aA^'^ dependence in the lower frequency region was observed and is explained in terms of a frequency dependent layer reflection phenomena. The spectra of the envelope of

the scattered signal are also given. They are generally Gaussian in shape with the

width dependent upon the range, frequency and scattering angle. Other details of

their fine structure are also discussed. (Met. Abs. 14. 2-120) —Authors' abstract.

E-853 Pappas, C.F. ; Vogler, L.E.and Rice, P.L., Graphical determination of radio

ray bending in an exponential atmosphere . U.S. National Bureau of Standards,

Journal of Research, Sec. D, 65(2): 175-179, March/April 1961. 7 figs. , table,

4 refs. , 4 eqs. DWB, DLC—This paper presents a simple engineering method for

calculating the amount of bending undergone by a radio ray passing through an ex- ponential model atmosphere. For any initial takeoff angle and for values of the

surface refractivity ranging from 200 to 450, the bending angle may be determined
215

as a function of height above the earth's surface, using a few graphs and a few calculations. Indications of the accuracy of the method are given at the end of this

paper. (Met. Abs. 13. 7-126) --Authors' abstract.

Parry, Charles A. , Equipment configuration and performance criteria for fully

optimized tropospheric scatter systems . IRE Transactions on Communications

Systems, N. Y. , 9(4):427-433, Dec. 1961. 4 figs. , 2 tables, 19 refs. , 15 eqs.

DLC--The optimum system is examined with the aid of a basic equation related to channel SNR. Expressions are then developed which show that for equal channel

loading and capacity, FM systems are likely to be superior to SSB systems for

normal voice channel operation. Further improvement in FM performance may be

achieved with phase locked receivers. Performance equations for such receivers

are used in basic expressions for optimized scatter circuits to express channel

capacity as a function of maximum distance for minimum power. From this equipment configurations for various performance capabilities are developed. These

data then give the maximum capability of the tropospheric scatter system when

all relevant design parameters are optimized. --From author's abstract.

Prosin, A. V. , Calculation of cross noise power in long distance scatter communication systems . Radio Engineering and Electronic Physics, N. Y. , No. 1:9-18,

1961. 4 figs. , table, 8 refs. , 53 eqs. Transl. of original Russian in Radiotekhnika i Elektronika, Moscow, 6(1): 14-24, Jan. 1961. DLC--The paper determines

the cross noise power arising in long distance communications systems with fre- quency modulation and frequency multiplex, due to the multipath propagation of

radio waves. It is shown that in the presence of the constant component of the

field the value of cross noise in telephone communications channels using long

distance tropospheric microwave propagation may be extremely small. --Author's

abstract.

Prosin, A.V. , Calculation of reliability of tropospheric communication system in

the presence of correlated fading. Radio Engineering and Electronic Physics,

N. Y. , No. 9:1407-1410, 1961. 2 refs. , 26 eqs. Transl. of original Russian in

Radiotekhnika i Elektronika, Moscow, 6(9): 1578-1580, Sept. 1961. DLC--An

analysis of the presented calculations shows that the reliability of a communication system in the case of separated reception increases appreciably as the power

of the constant signal increases compared with the power of the random signal.

The reliability is least when only the random component of the field is present at the point of reception. An increase in the coefficient of correlation between the

separated signals greatly reduces the reliability of the communication. --E. K.

Prosin, A.V. , On the calculation of the bandwidth in UHF tropospheric scatter

propagation. Radio Engineering and Electronic Physics, N. Y. , No. 8:1234-1236,

1961. Fig. , 4 refs. , 17 eqs. Transl. of original Russian in Radiotekhnika i Elektronika, Moscow, 6(8): 1392-1394, Aug. 1961. DLC--In this brief communication an attempt is made to determine the bandwidth of the troposphere in the

presence of a constant field and scattered field at the reception point. It has

been found that the bandwidth of the troposphere increases with increasing effective band, intensity of the constant wave, and coefficient of the frequency correlation, --E.K.
216

E-S58 Prosin, A.V., Transient noise in two path radiowave propagation. Radio Engineering and Electronic Physics, N. Y. , No. 11:1722-1726, 1961. 3 figs. , table,

2 refs. , 17+ eqs. Transl. of original Russian in Radiotekhnika i Elektronika,

Moscow, 6(11): 1932-1936, Nov. 1961. DLC -In this brief note author presents

a procedure for calculating the transient noise occurring in two path propagation

of radiowaves, for the special case when automatic frequency control of the transmitter is used to select the optimum operating point on the phase characteristics

of the two path channel. --E. K.

E-859 Rai, D.B. , Role of tropospheric scatter in radar propagation. Institution of Telecommunication Engineers, New Delhi, Journal, 7(5):220-224, Sept. 1961. 4 figs. , 6 refs. , 7 eqs. DBS--Two instances of radar echoes believed to be caused by scatter propagation are presented and discussed in relation to the prevailing atmospheric conditions. Obukhov's mixing theory appears to be more suited to the present observations and is applied for the estimation of the dielectric fluctuations and

gradients required to account for these echoes. The values obtained are found to be within reasonable limits. At near horizontal incidence direct backscatter is a contributing factor at short ranges, but at longer ranges the echoes are exclussively due to return from terrain through forward scatter. At high antenna elevations only direct backscatter appears to be significant. --Author's abstract.

E-860 Rai, D.B. (India Meteorological Dept. ), Some aspects of anomalous propagation

at 3 cm wavelength. Institution of Telecommunication Engineers, New Delhi,

Journal, 7(4):177-180, July 1961. 6 figs. , 3 refs. DBS-Some cases of superrefraction observed with 3 cm radar at different stations in India have been analyzed.

One of the significant features is the asymmetrical distribution of the duct with

respect to the station; another is the fictitious display of some target heights.

Ducts appear to be effectively present only in the small scale anticyclonic regions near the station. The spurious height of the echoes is attributed to the presence

of a sufficiently thick duct allowing different Gamow modes for different angles of

aerial elevation. --Author's abstract.

E-861 Ringwalt, D.L.and MacDonald, F.C., Elevated duct propagation in the tradewinds . IRE Transactions on Antennas and Propagation, 9(4):377-383, July 1961.

11 figs. , 2 tables, 5 refs. DLC--Report on the experimental transmission using

220 Mc over the sea path between Brazil and Ascension Island during Nov. 1959.

It was found that the long range propagation (500-1200 mi) was due to a strong

duct near 6000 ft altitude, cloud base (2000 ft) which influenced range very little,

if any. Radio signal fluctuation rate independent of maximum propagation range,

though slow fade rate usually were associated. Field strength measurements at 4000 ft were 40 db>than those at lower levels, at 6000 ft decrease was slow to

10, 000 ft. --W. N.

E-862 Santomauro, Luigi, Preliminari per uno studio suU'andamento deU'indice di

rifrazione relativo alle microonde. nei bassi strati atmosferici. (Preliminaries for a study of variations of the microwave refractive index in the low atmospheric layers. ) Rivista di Meteorologia Aeronautica, Rome, 21(3):23-40, July/Sept. 1961.

5 figs. , 6 tables, 4 refs. , 9 eqs. Italian, French, English and German summaries

p. 23. DLC --This research, the first of its kind, has been carried out at the re- quest of the U.S. Air Weather Service, and deals with the index of diffusion of

microwaves in lower atmospheric layers (up to 1500 m). The theories of refractive

index and of the standard and anomalous propagation of microwaves are presented;

then follows the calculation of refractive index, by means of L. J. ANDERSON'S

duly modified slide rule. The graphic representation in time and space of the
217

modified refractive index behavior (M) for the winter 1959-60 and for Milan area,

is then given as an example. The tabulated data concerning atmospheric pressure,

temperature, vapor pressure at 1000 m above the ground, as well as the indexes of

refraction (in whole N-units) for standard and intermediate levels up to 500 mb, are

finally given for the same area. (Met. Abs. 13. 5-126) -Author's abstract.

E-863 Shaft, Paul D. , Information bandwidth of tropospheric scatter systems . IRE Transactions on Communications Systems, N. Y. , 9(3):280-287, Sept. 1961. 9 figs. , 6

tables, 12 refs. , 7 eqs. DLC--A set of design curves of peak intermodulation distortion due to frequency selective fading, as a function of information bandwidth,

is derived for tropospheric scatter systems. These curves are applicable to systems frequency modulated with frequency division multiplexed telephone and telegraph channels. A two ray tropospheric scatter model was selected in order to derive general results*. This, however, restricts the use of the design curves to the

region where the information bandwidth is less than the propagation bandwidth.

Equations for intermodulation distortion are evaluated for parameters normally en- countered in tropospheric scatter systems. A method of obtaining a probability

distribution of the distortion is indicated, and an example is worked out in detail.

The intermodulation distortion due to frequency selective fading will exceed the

thermal noise in some systems, and should be taken into consideration when designing tropospheric scatter systems. --Author's abstract.

E-864 Shur, A. A. and Maksimov, G.S., One method of measuring the fluctuation of the

phase of radiowaves in a study of tropospheric scatter propagation . Radio Engineering and Electronics, N. Y. , No. 5:734-735, May 1961. Fig., 3 refs. Transl.

from original Russian in Radiotekhnika i Elektronika, Moscow', 6(5):828-829, May

1961. DLC, DBS -Describes a simple method based on NYQUIST's principle for

measuring the phase fluctuations of radiowaves propagated in the troposphere.

--Electr. Engr. Abstract.

E-865 Sindler, Iu. B. , Concerning the accumulation of noise and fading in radio relay

communication line with long distance tropospheric propagation. Radio Engineering and Electronic Physics, N. Y. , No. 12:1876-1377, 1961. Ref. , 7 eqs. Transl.

of original Russian in Radiotekhnika i Elektronika, Moscow, 6(12), Dec. 1961.

DLC --In the investigation of processes occurring in radio relay lines with long distance tropospheric propagation, it is of interest to obtain an asymptotic estimate

of the noise distribution when slow fading in the neighboring sections is correlated.

An analysis shows that the asymptotic formula is valid also in the case when the

slow fading is synchronous (i. e. , the correlation coefficient is equal to unity).

Thus, in the case of complete correlation of the slow fading in neighboring sections and when the values of the fadings in these sections are independent, the

asymetric properties of the distribution of the total noise turns out to be the same.

»E. K.

E-866 Smith-Rose, R.L. , Fifty years' research in radio wave propagation . Wireless

World, London, 67(4) -.203-207, April 1961. 2 figs. --A brief history of the progress

of research and understanding of the mechanism of radiowave propagation since

1911. Previous to that time it had been thought that radiowaves travelled over the

surface of the earth. The possibility of an ionospheric layer refracting the radiowaves was first visualized in 1912 at a meeting of the British Association. It was

shortly after this that a series of international meetings began which led to the for- mation of the U. R.S. I. in 1922. It was in 1925 that APPLETON carried out his

series of experiments which first definitely demonstrated the existence of the ionosphere. The discovery of the E and F layer followed. More recently it has been
218

possible to experiment with more powerful techniques using radar. Propagation at VHF was developed to ensure greater reliability of service. Possible trends in

future research are discussed in the light of the conclusions and recommendations

of the various Commissions of the U. R.S.I. (Met. Abs. 13. 3-99)- -R. B.

E-867 Stein, S. and Johansen, D. E. , A theory of antenna performance in scatter type re- ception. IRE Transactions on Antennas and Propagation, N. Y. , 9(3):304-311, May

1961. 4 figs. , 14 refs. , 32 eqs. DLC--The results of this theoretical investigation enable evaluation of efficiency of antennas. The model consists of a receiving antenna viewing a site of radio sources, on an idealized celestial sphere.

Comparison shows existence of a significant gap between performance of current

or contemplated systems, and the theoretical optimum. --W. N.

E-868 Thayer, G. D. , A formula for radio ray refraction in an exponential atmosphere . U.S. National Bureau of Standards, Journal of Research, Sec. D, 65(2): 181-182,

March/April 1961. Fig. , 5 refs. , 6 eqs. DWB, DLC--A formula for the radio ray

refraction angle is derived by integration of the approximate differential equation

for the case where the refractivity, (n-1) 10^, decreases exponentially with height

above the surface of a smooth, spherical earth. The solution is in terms of the

widely tabulated exponential and error functions, and is accurate to within 4% over

the useful range of the variables employed. (Met. Abs. 13. 7-127) --Author's abstract.

E-869 U.S. Naval Research Lab. , Elevated duct propagation in the trade winds . Prepared

by Wave Propagation Branch. Its NRL Report 5602, June 1, 1961. 38 p. 15 figs.,

2 tables, 5 refs. DWB (M(055) U586r)--All of the maximum propagation ranges (at

220 Mc/s) observed in the present study in an elevated duct region varied from 500

to 1200 mi, compared to less than 400 mi observed with the same equipment outside

the duct. The measurements were made at the optimum season (Nov.) in a tradewind region between Brazil and Ascension Island (8°S lat.). The field strengths

above 4000 ft are as much as 40 db larger than those at lower altitudes. From the

level at average duct height (10,000 ft) the field decreases slowly to 6000 ft, the

maximum altitude investigated. The slow fading rate usually associated with duct

propagation is not always observed, even on the very long range runs. An extra- polation to propagation conditions in the month of March via refractive index measurements indicates minimal ducting conditions 10 to 20% of the time. (Met. Abs.

13. 6-105) -Author's abstract.

E-870 Wilson, Alvin C. (CRPL, Nat'l. Bur. Stds. , Boulder, Colo.), Measurements of low

angle radiation from a monopole. U.S. National Bureau of Standards, Journal of

Research, Sec. D, 65(6):641-645, Nov. /Dec. 1961. 4 figs. , 3 refs. , eq. DWB,

DLC --Experimental measurements using scale model techniques have been carried

out to determine the effectiveness of a ground system of long wire radials to obtain

low angles of departure of transmission. Since transmission was to be in one direction only, the ground wires were laid out to form a ground plane sector approximately 18 wide centered in the direction of transmission. The antenna was a base

driven vertical monopole. Measurements were made of the relative response in

decibels for the monopole used as a receiving antenna at a frequency of 400 Mc/s.

The target transmitter antenna was always located at a distance of 200 wavelengths.

At this separation the ground plane sector was in the near field of the target trans- mitting antenna and appropriate corrections must be made. The received signal

strength improvement due to the presence of the ground sector was approximately

14 db. The measured lobe positions of the first and second beam maximums and the

first null are in good agreement with theory. (Met. Abs. 14. 5-147) -Author's abstract.
219

E-871 Wolf, E. ; Kopeck, R.and Mondloch, A. (Sylvania Amherst Labs. , Buffalo, N. Y.),

Millimeter wavelength atmospheric absorption. Institute of Radio Engineers, N.Y. , Proceedings, 50(4, Pt. 1):478, April 1961. 2 refs. DLC, DBS --A two way communication link was set up with one terminal at Sylvania's Amherst Labs. , the other

6. 1 km away at the Univ. of Buffalo. The test frequency being used is 69. 9 kMc.

Preliminary results of the measurements show that on a sunny day with a temperature of 67°F and relative humidity of 68%, the attenuation is 1. 35 db/km. The discrepancy between this value and the theoretical 1. 27 db/km is attributed to inaccuracies in the measured noise figures. Measurements are being continued to es- tablish absorptions due to oxygen, uncondensed water vapor and light rain and fog.

-G.T.

E-872 Yoshino, Takeo (Univ. of Electro-Communications), Radio wave propagation on the

ice cap. Antarctic Record, Tokyo, No. 11:228-233, Jan. 1961. 13 figs. Japanese

summary p. 228. DWB--A brief report of a study of radio wave propagation in Antarctica. Measurements of specific dielectric constant and loss in high frequencies

are made by the tuning circuit resonance method for 1. 5 Mc and 10 Mc, and by us- ing the Lecher line for 100, 250, 300 and 3000 Mc. It was found that the snow and

ice composing the ice cap have an excellent insulating property for the electromagnetic waves of UHF or higher. Results of measurement of directional pattern, input

impedance characteristics and gain by setting a doublet antenna tuned for 100 Mc

and an 8 element YAGI beam antenna tuned for 300 Mc are included. One of the

main results was that the best type of antenna to be used was determined. (Met.

Abs. 15. 2-232) --E.Z.S.

E-873 Zinichev, V.A.; Ryzhov, Iu. A. and Iudin, O. I. , Metod issledovaniia radiovoln

v troposfere pod bol'shimi uglami. (Method of studying radio waves in the troposphere under large angles. ) U. S.S. R. Ministerstvo Vysshego i Srednego Spetsial 1- nogo Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 4(1):

177-178, 1961. 3 refs. DLC --The purpose of the method described in this note is to investigate the role of scattering in tropospheric radio wave propagation. It was

worked out and tried at the Radio Research Institute of Gorki University. A directive antenna is used; the angle of scattering is 20-60° and the distance between

transmitter and receiver about 25 km. By using large angles of scattering, diffraction and wave guide effects are eliminated. Preliminary results of experiments con- ducted with this technique yielded results which appear to be in agreement with the

theory of locally homogeneous turbulence worked out by Silverman (see E-416) and

Tatarskii (see E-676). --G.T.

1962

E-874 Anastassiades, M.A. ; Karapiperis, L. N. ; Kariambas, N. K. et al. (all, Univ.

of Athens), Prediction of the field strength fading forms bv means of weather situations. Geofisica Pura e Applicata, Milan, 52:143-152, May/Aug. 1962. 8 figs.,

2 tables, 2 refs. DWB, DLC--In this study the different forms of the electromagnetic field strength recordings at the Thera-Crete microwave link are examined, in

comparison with the corresponding weather situations prevailing over that area. According to the amplitude of fluctuations, the different forms of recordings have

been classified in three basic types A.B.C and the annual frequency of the appear- ance of these types has been observed. Finally, the influence of weather situations on radio wave propagation was examined and it has been found that in most cases a close relationship exists between weather situations and the different fading forms

of the electromagnetic field so that a prediction of the fading form may become possible by means of the weather forecast. --Authors' abstract.
220

E-875 Armand, N. A. etal. (Academy of Sciences, Moscow), Long range tropospheric

propagation of ultra-short radio waves . International Scientific Radio Union, Commission II on Radio and Troposphere, Monograph on radio wave propagation in the

troposphere: Proceedings of the Commission, 13th General Assembly of URSI,

London, 1960. Amsterdam, Elsevier Pub. Co. , 1962. p. 91-118. 9 figs. , 119 refs.

English and French summaries p. 91. DLC (QC973. 1575), DWB (M10. 62 I61mo)~

Experimental results on long range tropospheric propagation are reviewed and the

various signal characteristics poin ed out. Some aspects of radiometeorology and

of the theory of long range propegation are discussed; and an indication is given of

where further research in these iields is necessary. (Met. Abs. 14. 9-163) —Authors' abstract.

E-876 Armand, N. A. , O difraktsii radiovoln vokrug zemli v usloviiakh sloisto-neod- norodnoi' atmosfery. (Diffraction of radio waves around the Earth through inhomogeneous atmospheric layers. ) Radiotekhnika i Elektronika, Moscow, 7(2):223-

229, Feb. 1962. 18 refs. , 31 eqs. Transl. into English in Radio Engineering and

Electronic Physics, N. Y. , No. 2:206-212, Feb. 1962. DLC -The effect of nonlinear altitude profiles of the specific inductive capacitances of air during diffraction of ultrashort waves at the Earth's surface are examined. The problem is ana- lyzed by the method of reference equations. It is shown that the result depends on

the magnitude of the so called "Schwartz derivative". When the magnitude of this

derivative is small, the effect of nonlinearity of the altitude profile of the specific

inductive capacitance results in slight adjustments in the magnitude of the equivalent radius of the Earth. --Transl. of author's abstract.

E-877 Arsac, Jacques; Tremblay, Real and Simon, Jean-Claude, Propagation des ondes:

prodiffusion tropospherigue . (Wave propagation: tropospheric forward scattering.

)

Academie des Sciences, Paris, Comptes Rendus, 255(5) :984-986, July 30, 1962.

Fig., 2 refs. DWB, DLC --The inhomogeneities of the atmosphere are responsible

for the propagation of hertzian waves beyond the horizon. Disregarding any hypothesis on atmospheric structure, the author propounds that the fundamental phenomenon is a deformation of the wave fronts emitted which results from optical variation due to index heterogeneities, any absorption phenomenon being disregarded.

Three particularly important cases are considered: a) the inhomogeneities of the

atmosphere which have a stationary character; b) there exists in the atmosphere

a privileged horizontal layer where index fluctuations prevail, and c) the inhomogeneities moreover are localized in a layer of negligible thickness. The fluctuations of the wave propagation in time are linked with atmospheric motions. The

interpretation and the forecasting of tropospheric proscattering can be made without being obliged to make a hypothesis on the nature of the index fluctuations in

the atmosphere. The homogeneities considered cause a distortion of the phase

surface of a transmitted wave; they are stationary over large areas or on the contrary, limited to a rather thin layer in order to correctly describe the field fluctuations in terms of the frequency. It is sufficient to know that the atmospheric motions are entirely disorderly or on the contrary due to a steady wind for describing

the fluctuations in time, and in the latter case, they are described by the same

laws as the fluctuations in frequency. (Met. Abs. 14. 7-102)--A. V.
221

E-878 Arsen'ian, T.I. and Semenov, A. A., Sravnenie statisticheskikh kharakteristik

fluktuatsif polia priamoqo i otrazhennoqo siqnalov ukv v troposfere. (Comparison

of statistical characteristics of fluctuations in direct and reflected fields of microwave signals in the troposphere.) Radiotekhnika i Elektronika, Moscow, 7(10):

1699-1702, Oct. 1962. 3 figs. , 8 refs. , eq. Transl. into English in Radio Engineering and Electronic Physics, N. Y. , No. 10:1573-1576, Oct. 1962. DLC, DBS--

The report presents the experimental results of comparison of the statistical characteristics of fluctuations in the direct and reflected fields of microwave signals

under identical or similar propagation conditions. It is shown that the time autocorrelation functions of fluctuations in the direct and reflected signals coincide.

The space autocorrelation functions (transverse) undergo oscillations which are similar in nature in the direct and reflected signals. The experimental results are compared with the theoretical behavior of the space correlation for the special case of the correlation function for fluctuations in the refractive index of the me- dium in the form of a Gaussian curve. --Authors' abstract.

E-879 Bankston, L. and Fast, N. (both, Range Development Dept. ), Microwave refrac - tive climate of the lower 10. 000 ft of atmosphere over a portion of the North Pacific

Ocean. U.S.Pacific Missile Range, Point Mugu, Calif. , Technical Memorandum

62-4, July 3, 1962. 104 p. Mostly figs. , table, 5 refs. DWB (M10. 62 U585me)--

Knowledge of the microwave refractive climate over the North Pacific Ocean is important to the Pacific Missile Range. An estimate of this climate is given based

on small samples of radiosonde data. From these samples the means and standard

deviations of the refractivity are computed for each month for which data were

available. (Met. Abs. 14. 7-103) -Authors' abstract.

E-880 Barlow, Howard Everard Monteagle and Brown, J. (both, Univ. College, London),

Radio surface waves . Oxford, Clarendon Press, 1962. 200 p. Figs. , bibliog.

p. 187-195, eqs. Price: 42s. (International Monographs on Radio) DLC (QC661.

B264). Review by A. L.Cullen in Science Progress, London, 50(200):657, Oct.

1962. --This highly technical monograph is primarily concerned with the type of

electromagnetic wave, which may be described as one that propagates without

radiation along an interface between two different media. The treatment includes

the discussion of: conditions for the support of surface waves at an interface between two different homogeneous areas: power carried by surface waves; the azimuthal surface wave supported by a cylindrical surface; other types of surface

waves; radiation and discontinuities; application of surface waves, etc. --E. K.

E-881 Barsis, Albrecht P. and Johnson, Mary Ellen (both, CRPL, Nat'l.Bur. of Stds. , Boulder, Colo.), Prolonged space wave fadeouts in tropospheric propagation.

U.S. National Bureau of Standards, Journal of Research, Sec. D, 66(6):681-694,

Nov. /Dec. 1962. 14 figs. , 10 tables, 12 refs. , eq. DWB, DLC -This paper contains the results of studies performed during the last several years on the short

term variability of tropospheric signals received over within-the-horizon paths in

Colo, and Calif. Signal variations of the type observed over such paths have been

termed "prolonged space wave fadeouts". They are analyzed as a function of carrier frequency, path characteristics, and meteorological parameters. The study

also includes an evaluation of fadeouts observed over a path using a mountain

peak as a diffracting knife-edge obstacle between transmitter and receiver. Principal results show a stronger diurnal trend of fadeout incidence in continental

climates than in maritime climates. A significant dependence of the fadeout characteristics on the refractive index structure has been observed in maritime climates.

In general, fadeouts tend to be more frequent but of shorter duration for higher fre- quencies. There are also indications that the occurrence of fadeout is well
222

correlated on vertically spaced antennas. Thus, conventional space diversity

techniques may not be effective to increase the reliability of systems operating over within the horizon paths. (Met. Abs. 14. 8-130) --Authors' abstract.

E-882 Barsis, Albrecht P. ; Norton, K.A.and Rice, P.L. , Predicting the performance of

tropospheric communication links singly and in tandem. IRE Transactions on Communications Systems, N. Y. , 10(l):2-22, March 1962. 21 figs. , table, 18 refs. , 44 eqs. DLC--This performance prediction of long distance tropospheric communication circuits is based on the best available estimates, and is discussed in terms of

(1) "Service probability", and (2) "Time availability". Terms which stand for (1) a grade of service during a given percentage of time as a function of the system parameter and (2) expressed in percentage of all hours. A more detailed discussion of the

function will be published as NBS, Tech. Note No. 101. --W. N.

E-883 Barton, John H. , A selective survey of Soviet Bloc scatter development. IRE Transactions on Antennas and Propagation, N. Y. , 10(3):335-337, May 1962. 67 refs.

DLC --Lists 67 entries for the literature period 1956-1959. The brief discussion includes the development of the problem, ionospheric scatter, tropospheric scatter,

backscatter and meteor scatter. It is concluded that most of the Soviet bloc work

parallels that of the U.S.A. -W.N.

E-884 Bass, F. G. ; Kaner, E.A. and Pospelov, L.A. , Fliuktuatsii radiovoln v blizhneV zone nad ploskoi' poverkhnostiu razdela. (Radio wave fluctuations in a near zone

over a plane interface. ) U.S.S.R. Ministerstvo Vysshego i Srednego Spetsial'-

nogo Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 5(2):

255-259, 1962. 5 refs. , 15 eqs. English summary p. 259. DLC --An examination

is made of phase fluctuations and relative amplitude fluctuations of radio waves in

the troposphere over a perfectly conducting plane interface. In the limiting case

of near zone the amplitude and phase fluctuations are determined from partial phase

fluctuations in different regions of direct and reflected signals. A distribution law

is found for field component fluctuations, phases and amplitudes, the dependence

of the root-mean-square fluctuations on frequency, path length, polarization of ra- diation and heights of transmitter and receiver over the interface. Correlation of

phase and amplitude fluctuations are calculated for a transverse direction and the

region in the vicinity of the zeroes of the mean field (minima of lobes) is examined.

It is shown that the existence of an interface in the case of near zone causes a number of relationships of fluctuation characteristics which are different from those

which appear in the case of infinite space or in a distant zone in the presence of an

interface. --Authors' abstract.

E-885 Bazer, J. and Karp, S. N. , Propagation of plane electromagnetic waves past a shoreline . U. S. National Bureau of Standards, Journal of Research, Sec. D, 66(3):

319-334, May/June 1962. Figs., 28 refs. , numerous eqs. DWB, DLC -The problems of the diffraction of homogeneous plane waves and ground waves by a linear

shoreline in a planar land-sea surface are discussed. The direction of propagation

of these incident waves is assumed perpendicular, and that of their magnetic vectors parallel, to the shoreline. At the air-land interface, the customary impedance

boundary condition is imposed while the sea is treated as a perfect conductor;

atmosphere and ionospheric effects are ignored. Exact integral representations of

the solutions are presented. In the case of homogeneous plane wave excitation

originating over the sea, the integral representations are employed to obtain ex- pressions for the geometrical optics field and for the far field form of the remaining

scattered field, transition regions included. The possibility of coastal refraction

is discussed. --Authors' abstract.
223

E-886 Bean, Bradford R. (Central Radio Propagation Lab. , Nat'l. Bur. Stds. .Boulder,

Colo.), The radio refractive index of air. Institute of Radio Engineers, N. Y. , Proceedings, 50(3): 260-273, March 1962. 7 figs. , 9 tables, 51 refs. , 50 eqs.

Correction to Table 1, Ibid. , 50(6, Pt. 1):1520, June 1962. DLC--This is a tutorial

paper. The derivation of the classical Debye expression for the radio refractive

index is reviewed. Recent determinations of the constants in this expression are reviewed and the conclusion reached that differences between constants are small

compared with the error in using standard meteorological data in the formula. The

various transformations of refractive index data are discussed as a natural result

of the model assumed for its height distribution. The effect of the use of the vari- ous units is illustrated by examples drawn from radio climatology and the refraction of radio waves. --Author's abstract.

E-887 Bean, B.R. (Nat'l. Bur. of Stds. .Boulder, Colo. ); Fehlhaber.L. and Grosskopf, J. (both, Femmeldetechnische Zentralamt, Darmstadt, Germany), Comparative study

of the correlation of seasonal and diurnal cycles of transhorizon radio transmission

loss and surface refractivity. U.S. National Bureau of Standards, Journal of Research, Sec. D, 66(5): 593-599, Sept. /Oct. 1962. 12 figs. , 2 tables, 12 refs. , 7 eqs. DWB, DLC --Correlations between the surface refractivity, Ns, and trans- horizon recordings of VHF radio transmission loss are examined for 34 U.S. and

9 German radio paths. The largest correlations are found to be associated with

the seasonal cycle of nighttime recordings and diurnal cycles during the summer

months. The annual cycles may be represented by a single regression coefficient

of -0. 18 db/Ns for either night or day. The regression coefficients for the diurnal

cycles lie between -0. 2 and -1. 1 db/km and vary with distance and season, being

greatest between 175 and 200 km and in the winter months. A promising method of

estimating the within -month distribution of hourly median transmission loss is suggested by combining the seasonal and diurnal correlation analysis. It is indicated

that Ns provides as useful a prediction of diurnal and seasonal variations of monthly median values of transmission loss as radio measurements made over the actual

radio path in previous years. (Met. Abs. 14. 7-107) --Authors' abstract.

E-888 Blake, L.V. , Tropospheric absorption loss and noise temperature in the frequency

range 100-10.000 Mc. IRE Transactions on Antennas and Propagation, N. Y. , 10(1): 101-102, Jan. 1962. 6 figs. , table, 10 refs. DLC -This brief discussion on atmospheric absorption includes Blake's set of curves (pub. in NRL Rep. No. 5601,

1961). These curves permit direct readings of the total radar atmospheric attenuation as a function of total length of paths from 0° to 10° ray elevation angles.

Reference is also made to works by Bean and Abbott, Hogg and other researchers.

»W. N.

E-889 Boithias, Lucien and Misme, Pierre (both, Centre National d'Etudes des Telecommunications, (C.N. E.T.)), Le gradient equivalent: nouvelle determination et calcul qraphique. (Equivalent gradient: redetermination and graphical computation.

)

Annales des Telecommunications, Paris, 17(5/6): 134-139, May/June 1962. 8 figs.,

3 refs. , 7 eqs. DLC --For the determination of the atmospheric effect on trans- horizon radiowave propagation the curvature of the trajectories has to be computed.

Because of the complexity of the function N(h) of the refractive index N of the at- mosphere varying with the height h, the introduction of an equivalent gradient was

suggested, i. e. , a constant gradient in a ficititious atmosphere which in a final

result will produce the same total refraction effect as in a real atmosphere. A new

method in which the computation is carried out by a simplified graphical method

was presented. The computation consists of two parts: determination and drawing

of radio electric rays (trajectories) starting with the curve N(h) and the determination of the equivalent gradient in function of altitude at a specified distance.
224

Two operational modes: communications within visibility (radar) and transhorizon

transmissions were theoretically explained. (Met. Abs. 14. 7-11D--S. N.

E-890 Booker, Henry G. (Cornell Univ. , N. Y. ), Future of propagation research and

development . Institute of Radio Engineers, N. Y. , Proceedings, 50(5): 717-718,

May 1962. 10 foot-refs. DLC--It is predicted that the future of propagation re- search and development will involve: 1) worldwide radio communication via satellites; 2) greatly increased interest in the magnetosphere and the solar atmosphere;

3) greatly increased interest in the atmospheres and surfaces of planets; 4) a far wider interpretation of the notion of radio frequency, both at the lower and the

upper ends of the spectrum; 5) extensive use of new methods for investigating the

top side of the ionosphere by both reflection and scattering techniques; 6) the discovery of new phenomena by the use of large antennas, high power transmitters and

low noise receivers, and 7) greatly increased interest in the propagation of sonic

and tidal waves in the atmosphere. (Met. Abs. 14. 10-94) --Author's abstract.

E-891 Braude, S. la. and Kaner, E. A. , Fliuktuatsii radiovoln razlichnoi chastoty v troposfere. (Fluctuations of radio waves of different frequency in the troposphere.)

U. S. S. R. Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia

Vysshikh Uchebnykh Zavedenir", Radiofizika, 5(2):246-254, 1962. 3 figs. , 10 refs.,

35 eqs. English summary p. 254. DLC--The dependence of the correlation of radio

waves of different frequency in the troposphere on the frequency deviation is con- sidered for the cases of near and distant zone, in free space and in the presence of a plane interface. It is shown that in a near zone the coefficient of correlation is

independent of frequency deviation, while in a distant zone there is a strong dependence on frequency deviation when it has small values. The correlation factor

decreases sharply in this region and even changes its sign. Comparison of results

of the calculations with experimental data confirms the theoretical conclusions.

—Authors' abstract.

E-892 Bremmer, H. (Philips Res. Labs. , Eindhoven, Netherlands), Theory of wave propagation through a concentrically stratified troposphere with a smooth profile. Pt. 2. Expansion of the rigorous solution. U.S. National Bureau of Standards, Journal of

Research, Sec.D, 66(l):31-52, Jan. /Feb. 1962. 6 refs. , 124 eqs. DWB, DLC.

(For Pt. 1, see E-705)--This paper is concerned with the height gain differential

equation in order to obtain a series for the complete solution which starts with

the extended W. K. B. approximation discussed in Pt. I. The coefficients of this

equation depend for each mode among other things, on the parameters fixing the

refractive index profile. However, the explicit dependence on these parameters

-2/3 can only be given in terms of expansions with respect to (k a)~

4 (koa = circumference of the Earth divided by the wavelength). In turn, these expansions are derived with the aid of other ones for the complex turning point connected with the

height gain differential equation. The final expansion for the solution of the differential equation is substituted in the boundary condition at the Earth's surface.

This leads to corresponding expansions, with respect to (k a)-2/3 f of the quantity

u; (a), and next, of the eigenvalues I themselves. (Met. Abs. 13.9-107)

--Author's abstract.

E-893 Burrows, Charles R. (Datronics Engineers, Inc., Bethesda, Md. ), History of

radio wave propagation up to the end of World War I. Institute of Radio Engineers,

N.Y., Proceedings, 50(5) :682-684, May 1962. 37 refs. DLC -HERTZ in the

1880' s demonstrated electromagnetic wave propagation predicted by MAXWELL
225

from his equations in 1864. HEAVISIDE and KENNELLY postulated the ionosphere

to explain MARCONI's historical transatlantic reception of radio waves in 1901.

AUSTIN derived the first formula for radio propagation in 1911 from experimental

data in the kilometer wave length range taken in the daytime. Much theoretical

effort was expended on the effect of the electrical properties of the ground but the

problem was not resolved until later. WATSON, however, cleared up the problem

of diffraction around a perfectly conducting sphere in 1919. Up to the end of

World War I, it was generally believed that radio transmission improved with an

increase in wave length, so the experimental data are concentrated in this region.

(Met. Abs. 14. 10-95) -Author's abstract.

E-894 Chisholm, J. H. (Lincoln Lab. , M. I. T. ) et al. , Properties of 400 Mcps long distance tropospheric circuits. Institute of Radio Engineers, N. Y. , Proceedings,

50(12): 2464-2482/ Dec. 1962. 41 figs. , 12 refs. DLC -Measurements are reported on beyond-the-horizon propagation losses at 400 Mcps. Data are given on the los- ses and their variations from 98 to 830 mi beyond the horizon. The transmission

loss between isotropic antennas varies from about 190 db at 100 mi to about 300 db

at 800 mi distance. Also described are measurements of frequency selective fading, space diversity, and variations in the angle of arrival of the signals. --Author's abstract.

E-895 Crawford, Arthur B. (Bell Tel. Labs. , Red Bank, N. J. ), Experimental results from

investigations on wave propagation through the troposphere. International Scientific Radio Union, Commission II on the Radio and Troposphere, Monograph on

radio wave propagation in the troposphere: Proceedings of the Commission, 13th

General Assembly of the URSI, London, 1960. Amsterdam, Elsevier Pub. Co. , 1982. p. 3-15. 27 refs. English and French summaries p. 3. DLC (QC973.I575),

DWB (M10. 62 I61mo). Also in National Research Council, Wash. , D.C. , Publication No. 8880:95-107, 1961. DWB, DLC--This review is restricted to experimental work conducted in the U.S. since the last general assembly in 1957. The

subject is discussed in terms of: 1) propagation beyond the horizon (medium

range); 2) long range results; 3) propagation within the horizon and 4) tropospheric propagation in relation to communication via satellites. (Met. Abs.

14. 9-166)-= W.N.

E-896 Deam, A. P. (Univ. of Texas, Electrical Eng. Res. Lab. , Austin, Texas), Radio- sonde for atmospheric refractive index measurements . Review of Scientific Instru- ments, N.Y. , 33(4): 438-441, April 1962. 6 figs. , 4 foot-refs. DWB, DLCDetailed description of a reliable, light weight and inexpensive instrument to sample the atmosphere with a resonant cavity nominally resonant at 403 Mc/s,

extendable to higher frequencies, and capable of providing remote information.

The radiosonde shown photographically and in a circuit diagram has been tested;

two profiles are given. The instrument is also successfully usable in polarization studies, electron density measurements, etc. (Met. Abs. 14. 7-507)-- W. N.

E-897 Dennis, Arnett S. , Correlation between hourly median scattered signals and

simple refractivitv parameters . U.S. National Bureau of Standards, Journal of Research, Sec. D, 56(3): 285-289, May/June 1962. 4 figs. , 13 refs. , 3 eqs. DWB,

DLC --Measured signals on two tropospheric scatter links have been analyzed in

the light of radio refractivity profiles prepared from radiosonde data. On the shorter link (San Diego—Santa Ana, 85 mi) the basic transmission loss was found to be

approximately a linear function of a N, the change in radio refractivity from the

ground to a height of 1 km. On the longer (Cape Canaveral—New Providence Island,

Bahamas, 300 mi) the relationship between transmission loss and aN was non-
226

linear, and better results were obtained by averaging the refractivity gradient over 5000 ft. Correlation coefficients on the San Diego—Santa Ana link range from 0.39

in Aug. to 0.84 in Feb. On the Cape Canaveral—New Providence link the correlation factor is 0. 92. The results show the feasibility of forecasting signal-to-noise

ratios on over water tropospheric scatter communications systems on a daily or hourly basis. (Met. Abs. 13. 12-57) -Author's abstract.

E-898 Dezerega, Bartolome and Vollhardt, Dieter, Note sur des essais de propagation

par diffraction au Chili . (Note on cases of propagation by scattering in Chile.)

Annales des Telecommunications, Paris, 17(3/4) :89-90, March/April 1962. 4 figs.

DLC --Study of some particular cases of transhorizon propagation made in Chile.

The installation of an experimental arrangement for determining scattering on a ridge of the Cordillera de los Andes is described and some experimental results

are given. The author points out the possible role of a second ridge which influ- ences the functioning of the visible Earth's curvature. (Met. Abs. 14.3-158)

-A. V.

E-899 du Castel, Francois, Influence de la terre en propagation transhorizon. (Influence

of the Earth in transhorizon radio links.) Onde Electrique, Paris, 42(418): 48-66,

Jan. 1962. 7 figs. , 29 refs. DLC --This paper is the first summary in the French

language of the work of V.FOCK, of Leningrad Univ. , on diffraction and the first systematic application of FOCK's method to these problems. The author analyzes

the theoretical interpretations of the tropospheric propagation phenomena of ultrashort waves in which the influence of the Earth plays some role. The atmosphere

is considered as a macroscopic homogeneous medium, i. e. , producing only refraction phenomena. The terrestrial orography, on the other hand, produces diffraction

effects and the study of the influence of the Earth on the propagation of radiation

is essentially that of the diffraction phenomena. The results differ according to whether the Earth is considered as a smooth sphere or according to whether the relief is considered to play a leading role. The results differ also according to the

importance of the refraction phenomena with respect to the diffraction phenomena,

i. e. , according to the atmospheric model adopted. An atmosphere with a constant

refractive index suppresses the refraction phenomena and an atmosphere having an index varying linearly with altitude can be reduced to the preceding case by introducing an equivalent radioelectric ray. An atmosphere with uniform index variation

but with a nonconstant gradient can introduce phenomena of refraction and reflection,

partial or total, leading to a steering of the radiation. In spite of the rough approximation of such atmospheric models, the results of the diffraction theory may be of

interest in certain practical cases of evaluating the propagation diminution. (Met.

Abs. 14.8-13D--A.V.

E-900 du Castel, F. , Le role du processus de reflexion partielle dans la propagation des

ondes . (Role of partial reflection processes in wave propagation. ) Acta Technica,

Budapest, 39(1/2): 179-186, 1962. 4 figs. , 5 refs. French, English, German and

Russian summaries p. 185-186. --Investigation of the partial reflection of a beam

incident on an irregular surface of atmospheric discontinuity showed the existence

of a specular reflection term and of a diffuse one. The application of this investigation to the case of stable tropospheric layers coexistent with turbulent strata led

to a synthetic view of the transhorizon tropospheric propagation. The consideration

of both the partial reflection term and the diffuse reflection term allowed for the

evaluation of the work of the experimental observations. --Author's abstract.
227

E-901 du Castel, F. ; Misme, P. ; Spizzichino, A. et al. , On the role of the process of

reflection in radio wave propagation. U. S. National Bureau of Standards, Journal

of Research, Sec. D, 66(3): 273-284, May/June 1962. 11 figs. , 31 refs. , 73 eqs.

DWB, DLC --Nature offers numerous examples of irregular stratification of the me- dium for the propagation of radio wave. A study of the process of reflection in

such a medium distinguishes between specular reflection and diffuse reflection.

The phenomenon of transhorizon tropospheric propagation offers an example of the

application of such a process, necessary for the interpretation of experimental re- sults. Other examples are those of ionospheric propagation (sporadic E layer) and

propagation over an irregular ground surface (phenomenon of albedo). (Met. Abs.

13. 12-50) -Authors' abstract.

E-902 Flavell, R.G.andLane, J.A. (both, D.S. I. R. Radio Res. Station, Slough, Eng. ), Application of potential refractive index in tropospheric wave propagation. Journal

of Atmospheric and Terrestrial Physics, London, 24(l):47-56, Jan. 1962. 6 figs. , 5 refs. , 7 eqs. DLC --The paper discusses the concept of potential refractive index,

K, and its application in studies of VHF and UHF propagation. A rapid method of

deriving values of K from radiosonde data is summarized, and the results illustrate

the advantages of this parameter in investigations of the physical structure of the

troposphere. A simple technique for locating major layer type discontinuities is

suggested, and a correlation is established between the presence of such discontinuities and the reception of abnormally high signals over land paths in the fre- quency range 100-1000 Mc/s. (Met. Abs. 13. 11 -90) -Authors' abstract.

E-903 Freeman, J.J. (J. J. Freeman Associates, Inc. ,8416 Georgia Ave. .Silver Spring,

Md. ), Range error compensation for a troposphere with exponentially varying re- fractivity. U.S. National Bureau of Standards, Journal of Research, Sec. D, 66(6):

695-697, Nov. /Dec. 1962. Fig., 2 tables, 3 refs. , 15 eqs. DWB, DLC -An explicit formula for tropospheric range error is derived with a spherically symmetric

refractivity which varies exponentially with height. The correction is given as

function of surface refractivity and ray elevation angle, and its accuracy and limitations are discussed. (Met. Abs. 14. 10-98) --Author's abstract.

E-904 Fukushima, Madoka; Iriye, Hiromi and Akita, Kin-ichiro, Spatial distribution

characteristics of atmospheric refractive index from helicopter and kytoon observations. Japan. Radio Research Laboratories, Tokyo, Journal, 9(45): 369-383,

Sept. 1962. 13 figs. , 4 tables, 5 refs. , 3 eqs. DWB, DLC -Atmospheric refractivity profiles, elevated inversion layer characteristics and turbulence spectra were observed at elevations up to 2000 m MSL by the use of a helicopter and a kytoon, during Aug. 1960, to July to Aug. and Nov. 1961. It was found that the val- ue of k of the Earth's effective radius ka varied 1. 52 (Aug. 1960), 1. 59 (July-Aug.

1961) to 1.30 (Nov. 1961). Large scale elevated inversion layer characteristics were obtained with the extraordinarily intense and stable signals in UHF beyond

the horizon propagation. The turbulence spectra nearly approach a -2 power law

at high wave numbers. (Met. Abs. 14. 8-133) -Authors' abstract.

E-905 Funakawa, Kenji and Kato, Joji, Experimental studies of propaqational characters

of 8. 6 mm wave on the 24 km path. Japan. Radio Research Laboratories, Tokyo,

Journal, 9(45): 351 -367, Sept. 1962. 21 figs. , table, 9 refs. DWB, DLC-Propagation experiments of 8. 6 mm wave on the 24 km path have been carried out nearly

all the year round. From the results of the rain attenuation measurements, an empirical method was developed for the estimation of the long term distribution of

rain attenuation. During no rainfall period, the fading range is large in the morning
228

and about midnight in summer. The estimated value of absorption by water vapor

is somewhat larger thar. the value measured by Texas Univ. There is a fairly

noticeable correlation between the fading range and the appearance of temperature

inversion in the atmosphere. (Met. Abs. 14. 9-167) --Authors' abstract.

E-906 Furutsu, Koichi, Effect on ridge cliff and bluff at coastal line on ground radio waves. Japan. Radio Research Labs. , Tokyo, Journal, 9(41):85-122, Jan. 1962.

Figs. , 7 refs. , 15 eqs. DWB, DLC --Semi -theoretical problems of radio waves

along an inhomogeneous earth have been treated for a smooth earth but not for ter- rain having elevations like in the case of a coast line. In this paper, the effects

of ridge, cliff and bluff at coastal lines on ground radio waves are computed and

displayed in sets of charts for medium and low frequencies in a wide range of

parameters. The formulas are applications of the theory which appeared in other

papers. As expected, a ridge on lossy ground has an obstacle gain even though

the ground be a plane, when the Sommerfeld numerical distance from the ridge is

sufficiently large. Also when the radio waves propagate across a coastal line

having a bluff, the rate of change of the relative phase with the propagation distance over sea becomes larger as the height of the bluff increases and is sometimes much more than that without a bluff. --Author's abstract.

E-907 Gerks, I.H. , Use of a high speed computer for ground wave calculations. IRE

Transactions on Antennas and Propagation, N. Y. , 10(3): 292-298, May 1962. 6

figs. , 4 tables, 10 refs. , 41 eqs. DLC --Outlines mathematical methods and programming by which the field strength relative to free space can be calculated

when ionosphere is neglected and tropospheric refraction is approximated by appropriate constant gradient of the refractive index. Two programs, one on the

plane earth approximation and the other on a spherical Earth were tested with an IBM 650 computer. --W. N.

E-908 Glenn, A.B. and Lieberman, G. , Effect of propagation fading and antenna fluctuations on communication systems in a jamming environment. IRE Transactions on Communications Systems, N. Y. , 10(l):43-60, March 1962. 22 figs. , table, 7

refs. , 96 eqs. DLC --Interference on propagation fading with and without antenna

fluctuations were studied individually, summarized and classified accordingly.

Formulas derived for 9 basic situations (of which 6 were studied) are applicable

to system margin calculations for different fading conditions and antenna gain

variances. —W. N.

E-909 Gordon, W. E. (Air Force Arecibo Radio Obs. , Puerto Rico), Physical character- istics of the troposphere. International Scientific Radio Union. Commission II on Radio and Troposphere, Monograph on radio wave propagation in the troposphere:

Proceedings of the Commission, 13th General Assembly of URSI, London, 1960.

Amsterdam, Elsevier Pub. Co. , 1962. p. 59-64. 5 figs. , 9 refs. English and

French summaries p. 59. DLC (QC973. 1575) , DWB (M10. 62 I61mo) -Recent

studies in the U.S. of the physical characteristics of the troposphere related to radio propagation are considered. The characteristics are discussed under two

broad headings: synoptic scale and irregularities. The characteristics pertinent

to a synoptic scale include: an exponential model of the atmosphere, elevated lay- ers (particularly in the trade wind regions) and the climatology of refractivity near

the ground. The irregularity characteristics include the spectrum of the fluctuations

and the effect of thermal stability o« the spectrum. (Met. Abs. 14. 9-168) -Author's

abstract.
229

E-910 Gossard, Earl E. , The reflection of microwaves by a refractive layer perturbed by

waves. IRE Transactions on Antennas and Propagation, N. Y. , 10(3):317-325,

May 1962. 13 figs. , 8 refs. , 38 eqs. DLC --Effects of internal tropospheric waves

on radio and radar performance are discussed, including description of the waves

and their theoretical explanation. Power spectra of amplitude and slope of several cases on a radio refractive layer are shown. --W. N.

E-911 Gough, M. W. , Propagation influences in microwave link operation. British Institution of Radio Engineers, London, Journal, 24(l):53-72, July 1962. 28 figs. , 33

refs. , 17 eqs. DBS --Basic characteristics of ground-to-ground propagation in the

frequency band 50-10,000 Mc/s are discussed, with emphasis on the operation of

point-to-point radio links. Practical applications of such knowledge are illustrated

by appraisals of the use of flat radio mirrors for circumventing mountain obstruction on microwave radio lints, and of the capabilities of large aperture aerials and

space diversity systems in reducing fading. Ground reflections are shown to be a large factor in the performance of very short wave radio links and the influence of

inhomogeneities in the lower atmosphere is also stressed. It is pointed out how

statistical analysis of temporal and spatial strength variations can often reveal the

nature of the propagation mechanism at work, while at the same time, pointing the

way to improvements in circuit reliability. --Author's abstract.

E-912 Grosskopf, J. (Fernmeldtechnisches Zentralamt, Darmstadt, Germany), Fading;

investigations for tropospheric propagation paths. International Scientific Radio

Union. Commission II on Radio and Troposphere, Monograph on radio wave propagation in the troposphere: Proceedings of the Commission, 13th General Assembly

of URSI, London, 1960. Amsterdam, Elsevier Pub. Co. , 1962. p. 39-50. 7 figs. , table. English and French summaries p. 39. DLC (QC973. 1575), DWB (M10. 62

I61mo)--An analysis of fading records obtained in West Germany, with transmissions on frequencies in the region of 100, 200, 500 and 2000 Mc/s over paths of

the order of 240 to 250 km in length. The analysis is confined to scatter-type signals. Auto-correlation functions of the field strength variations on all 4 frequencies have been examined. While the exact form of the function is not yet established, it is clear that it is frequency dependent and that it is not a simple Gaussian function. Cross correlation studies, with vertically spaced aerials at 2000

Mc/s, in conjunction with the autocorrelation measurements, indicate the exist- ence of a vertical drift of the scatter medium. (Met. Abs. 14. 9-169)—Author's

abstract.

E-913 Grosskopf, J. and Fehlhaber, L. , Haufigkeit und Dauer einzelner Schwundeinbruche bei troposphaVischen Scatterstrecken. (Frequency and duration of single fading irruptions on tropospheric scatter paths. ) NTZ Nachrichtentechnische Zeitschrift, Brunswick, 15(2):71-78, Feb. 1962. 16 figs. , 2 tables, 4 refs. , 16 eqs.

DLC --Observations of fading phenomena were made on 3 links of lengths 194, 242

and 393 km, respectively, at frequencies between 100 and 2000 Mc/s. From the

result obtained, the short time distribution of fading duration on tropospheric scatter path can be determined. The long period distribution of the mean fading fre- quency was obtained from observations during a whole year on a 100 Mc/s path.

The relation between the long period mean field strength, the fading frequency and

the operating frequency is not sufficiently well known. --Electr. Eng. Abstract.
230

E-914 Hansel, Christian (Geophy. Inst, der Karl-Marx-Univ. , Leipzig) , Ein Verqleich von UKW-Feldstarkemessunqen mit meteoroloqischen Zustandsanderuncren. (Comparison

of VHF field intensity measurements with changes in meteorological conditions.

)

Zeitschrift fur Meteorologie, Berlin, 16(1/2) :34-40, Jan. /Feb. 1962. 3 figs. , 8

refs. German and English summaries p. 34. DWB, DLC--Time variations of the ver- tical gradient of the refractive index, obtained from meteorological measurements

of a mountain and a flat country station, are compared with actual diurnal variations of the VHF receiving field strength. Sufficient interpretation of field strength

variations may be obtained from changes of refraction conditions. There is evidence of the receiving strength being particularly modified by meteorological conditions below the intersection of the tangential surfaces going through the transmitting and receiving antennas. (Met. Abs. 14. ll-lll)--Author's abstract.

E-915 Hay, D.R.and Pemberton, E.V. (both, Univ. of Western Ontario. E. V. Pemberton

now at Univ. Saskatchewan), On the eddy transfer of water vapor above an outdoor

surface. Canadian Journal of Physics, Ottawa, 40(9): 1182-1190, Sept. 1962. 3

figs. , table, 30 refs. , 5 eqs. DWB, DLC --Fluctuations in the refractive index of

the air above an outdoor surface have been examined by a 180 ft microwave interferometer. The observed standard deviations of refractivity are less than 10*".

These deviations are associated with instability of the air at the interferometer

path but not with instability of the air immediately above it. Smallest refractivity

deviations occur for weak eddy transfer of water vapor downward through moist air

in the radio path; intermediate deviations are associated with strong eddy transfer

of vapor upward through drier air in the path. Largest refractivity deviations are observed for less vigorous upward transfer of water vapor from the surface. It is

suggested that the more vigorous eddies disperse the entrained water vapor more

rapidly into smaller eddies than do the less vigorous eddies; and hence, lesser

local fluctuations in air refractivity appear along an extended path that is highly

unstable than along the same path under conditions of greater stability. (Met.

Abs. 14. 3-159) -Authors' abstract.

E-916 Hay, D.R.and Reid, W. M. , Radar angels in the lower troposphere . Canadian

Journal of Physics, Ottawa, 40(1): 128-138, Jan. 1962. 4 figs. , 3 tables, 27 refs.

DWB, DLC —A study of radar angels at 6800 Mc/s has been carried out at London,

Canada, over a period of 1 yr. Examination of the clear air reflections from

heights between 300 and 1500 m above the vertically directed radar has shown that

persistent angels occur for surface air temperatures between 30° and 50°F, and

that transitory angels are present for surface temperatures above 20°F that are out- side of this range. The maximum incidence of angels increases with type of air

mass in the order cA, mA, mP, mT, although the most common duration is approximately the same in these air masses. If the angel is due to reflection at a horizontal flat stratum, the power reflection coefficient of the stratum lies between 10*16

and 10"--"* for transitory angels and is as large as 10"!-- for persistent angels. It is shown that transitory angels may arise through eddy mixing in the lower troposphere when refractivity contrasts of about one part per million occur, but that the

reflecting stratum must be no more than a few centimeters in depth. It appears

that persistent angels are associated with a high concentration of moisture at the

ground, but their physical origin is not clear. (Met. Abs. 13. 8-515) --Authors'

abstract.
231

Herbstreit, J. W. (Nat'l. Bur. of Standards, Boulder) , Radio refractometry. International Scientific Radio Union. Commission II on Radio and Troposphere, Monograph on radio wave propagation in the troposphere: Proceedings of the Commission, 13th General Assembly of URSI, London, 1960. Amsterdam, Elsvier Pub. Co.

1962. p. 187-196. Table, 44 refs. , 2 eqs. English and French summaries p. 187.

DLC (QC973. 1575), DWB (M10. 62 I61mo)--A discussion of the refractive index

measurement of the troposphere at radio frequencies, with particular reference to measurements made by the radiosonde technique and by radio refractometers. The

application of radio refractometry to propagation problems is also considered.

(Met. Abs. 14. 9-171) -Author's abstract.

Hogg, D.C., The aperture to medium coupling loss in beyond horizon propagation . Institute of Radio Engineers, Proceedings, N. Y. , 50(1):1529, Jan. 1962. Fig.,

foot-refs. DLC --The note suggests a curve based upon experimental data for evaluating coupling loss when narrow beam antennas are used in tropospheric propagation beyond the horizon. The dependence of the coupling loss on path length and

frequency is not fully understood. It is concluded that more long term experimental data are needed to clarify the situation. --E. K.

International Scientific Radio Union. Commission II on Radio and Troposphere,

Monograph on radio wave propagation in the troposphere: Proceedings of the Commission II on radio and troposphere during the 13th General Assembly of URSI,

London. Sept. 1962 (i. e. , 1960). Ed. by J. A.Saxton. Amsterdam, Elsevier Pub.

Co. , 1962. 199 p. Figs. , tables, refs. , eqs. (International Scientific Radio

Union, URSI Monographs). --The 12 invited papers are in either English or French,

furnished with abstracts and bibliographic references. The papers are classified

into the following 4 sections at the end of which the ensuing discussions of the

papers are summarized, (i) Experimental data on tropospheric propagation, (4

papers); (ii) Physical characteristics of the troposphere (4 papers); (iii) Tropospheric propagation theories (2 papers); and (iv) Radio meteorology and climatology (2 papers). (For abstracts of the individual papers see E-716, 785 - 787,

875, 895, 909, 912, 917, 923, 932, 936, 942, 944). (Met. Abs. 14.10-7)

--W. N.

Knudtzon, N. , Shape's troposcatter systems in Norway. Teknisk Ukeblad, Oslo,

109(48): 1241-1254, Dec. 27, 1982. (Unchecked) -This is a survey of the telecommunications system of Allied Command Europe, which includes the ACE High troposcatter system extending from northern Norway to eastern Turkey. A review of

troposcatter theories and characteristics is given. The 3 leg "Hot line" system

between Oslo and Bodo7

, built in 1956/1958 to obtain experience for the planning

of the ACE High system is described with details of construction work and costs.

A selection of results of a program of measurements is also given; these measure- ments were taken for the planning of the ACE High system and relate to signal

variations and fading, intermodulation noise, parametric amplifiers, reflections

from aircraft. ACE High has a capacity corresponding to 36 telephone channels.

--Electr. Engr. Abstract.

Koido, H. , Case study of the relationship between meteorological conditions and

fluctuations of field intensity of radio waves in the Ryukyu Islands. Journal of

Meteorological Research, Tokyo, 14(8): 545-550, Aug. 1962. 4 figs. , table, 2

refs. In Japanese; English summary p. 545. DWB, DLC--In connection with the

propagation study of VHF and UHF waves for telephone and TV networks in the

Nansei Islands, a practical test beyond the horizon was carried out with 970 Mc
232

and 265.3 Mc waves in the period March 10 - May 1, 1960. Using the results of

this test and the simultaneous aerological observations obtained in this district,

relationships between meteorological conditions and the accompanying fluctuations of field intensity were analyzed. Some features of fluctuations in field intensity due to characteristic changes of meteorological conditions are shown.

The results are as follows: 1) Unstable fluctuations are likely to occur when an

inversion layer exists near the 900 mb surface. 2) The above condition seems to occur when the said district is in the southwestern domain of a traveling high from

China. 3) Unstable conditions are found at the passage of cold and warm fronts.

4) Unstable conditions are also found near the center of low and the convergence

zone of a stationary front. The unstable conditions are the results of irregularity

of refraction which comes from irregular distribution of water vapor in the atmosphere. (Met. Abs. 15. 2-34) -Author's abstract.

E-922 Koono, Tetsuo; Hirai, Masaichi; Inoue, Ryosuke and Ishizawa, Yoshihiro,

Antenna beam deflection loss and signal amplitude correlation in angle diversity

reception in UHF beyond horizon communications. Japan. Radio Research Labs. , Tokyo, Journal, 9(41):21-49, Jan. 1962. 16 figs. , 2 tables, 6 refs. , 54 eqs.

DWB, DLC--A loss due to deflection of antenna beam and an amplitude correlation

between signals received in the angle diversity reception in UHF beyond horizon

communications are studied experimentally and theoretically. The principal re- searches are made by utilizing the results obtained from antenna beam swing measurements. It is noteworthy that the scatter wave and the so-called elevated layer

reflection wave can be found as separated distinctly in the beam swing measurements. Theoretical formulas are derived for the antenna beam deflection loss and

for the angle diversity correlation in the scatter wave propagation. These are applied to the elevated layer reflection propagation. Fairly good coincidences

are found between the experimental and theoretical results, but more studies are needed for the angle diversity correlation in the elevated layer reflection propagation. --Authors' abstract.

E-923 Krasilnikov, V. A. and Tatarskii, V.I. (both, Academy of Science, Moscow),

Atmospheric turbulence and radio wave propagation. International Scientific Radio

Union. Commission II on Radio and Troposphere, Monograph on radio wave propagation in the troposphere: Proceedings of the Commission, 13th General Assembly

of URSI, London, 1960. Amsterdam, Elsevier Pub. Co. , 1962. p. 145-160. 3 figs.,

30 refs. English and French summaries p. 145. DLC (QC973. 1575) , DWB (M10.

62 I61mo)--The aim of this work is to consider the tropospheric radio wave propagation beyond the horizon and also of the fluctuations of elements of the waves from

the point of view of Kolmogorov-Obukhov's local isotropy theory of turbulence.

This theory has now been well developed, and numerous experimental investigations show that it satisfactorily describes the principal phenomena of the phase

and amplitude fluctuations. This theory also gives the right order of value for the

effective cross section of scattering in the transhorizon propagation. However,

it is impossible to explain the fields observed beyond the horizon solely by means

of this theory. (Met. Abs. 14. 9-172) -Authors' abstract.

E-924 Krylov, G. N. , Rasprostranenie radioimpul'sa nad ploskoi' odnorodnoi' zemlei.

(Propagation of radio pulses over a flat homogeneous earth. ) Radiotekhnika i Elektronika, Moscow, 7(4):579-589, April 1962. 9 refs. , 30 eqs. Transl. into

English in Radio Engineering and Electronic Physics, N. Y. , No. 4:549-558, April

1962. DBS, DLC --The present article attempts a rigorous solution of the problem

involving the propagation of pulses of arbitrary shape over a flat earth of arbitrary permittivity and conductivity. Approximate expressions are obtained for
233

calculating the field in the cases of radio and video pulse propagation. In their

final form the equations may be effectively applied to the calculation of the vertical component of the electrical field, especially if electronic computers are used. --Author's abstract.

E-925 Kulshrestha, S.M. (Met. Office, New Delhi), Further evidence of "abnormal"

superrefraction . Indian Journal of Meteorology and Geophysics, Delhi, 13(1):

135-137, Jan. 1962. 2 figs. , table, refs. DWB, DLC -Discusses a case of abnormal superrefraction recorded by the 3 cm CPS-9 radar at Safdarjung Airport on

April 14, 1962 (New Delhi) with a view to provide further evidence of the correct- ness of the ideas put forth by MATHUR and KULSHRESTHA. The weather recorded

at Safdarjung Observatory is tabulated, the PPI photograph is reproduced and a map of the area covered by the photograph is presented. It is stated that the

weather observations in the present case fully support the earlier ideas as con- cerns the occurrence of rainfall, the cooling at Earth's surface of the order of

10° C, light wind after the thunderstorm had passed, the cloudy sky thereafter,

and the frontal characteristic of the storm. (Met. Abs. 14B-245)--D. B. K.

E-926 Kulshrestha, S.M., Hot weather angels associated with high level temperature

inversions . Indian Journal of Meteorology and Geophysics, Delhi, 13(2): 218-226,

April 1962. 8 figs. , table, 4 refs. DWB, DLC--During the hot weather months

(April to June), the CPS-9 radar installed at Safdarjung Airport, New Delhi, has

been recording angel echoes having certain peculiar characteristics; the most important among them being the apparent association of the angel activity with an upper level temperature inversion or an isothermal layer between 6 to 11 km above

ground. Examples of this type of angel activity, observed on 7 different dates

spread over a 3 yr period (1958-1960) are presented and their characteristics discussed in this paper. Their apparent association with high level temperature in- version is also explained. (Met. Abs. 14. 6-629) --Author's abstract.

E-927 Latorre, V.R., A new scattering coefficient for tropospheric scatter propagation.

IRE Transactions on Antennas and Propagation, N. Y. , 10(4): 471 -472, July 1962.

2 figs. , 7 refs. , 9 eqs. DLC--This brief communication presents a determination

of a scattering coefficient from the basic propagation loss curves experimentally

determined by Collins Radio Company. --E.K.

E-928 Laurens, A.. , Television tropospheric scatter link between France and North Africa . Philips Telecommunication Review, Hilversum, 23(4): 149-166, Oct. 1962. 18 figs.,

2 tables, 11 refs. DLC--The tropospheric scatter circuit used to transport television signals between France and Algiers spans the distance in two hops; the intermediate station is on Majorca in the Balearic Islands. The circuit offers the

following 3 possibilities: a) transmission of a single program to North Africa with

quadruple diversity reception; b) transmission of two programs to North Africa

with dual diversity reception; c) transmission of a single program to France with

dual diversity reception. The frequencies used are in the Gc/s band, and the out- put power of the transmitter is 500 w. The properties of a tropospheric scatter

link and the results deduced from observation of variations in the received signal

strength are discussed. --Author's abstract.
234

E-929 McGavin, R.E. , Survey of the techniques for measuring the radio refractive index.

U.S. National Bureau of Standards, Technical Note, No. 99, May 1962. 37 p. 10

figs. , table, 26 refs. , 8 eqs. DWB (M(044) U585te)--The radio refractive index can be measured either directly or indirectly. The former method is utilized by

radio frequency refractometer; the latter method involves measurement of temperature, pressure and humidity and conversion to refractive index. In terms of con- venience and accuracy the direct method is superior; however, lack of the universal use of refractometers requires the use of weather service type of data for the

bulk of refractive index structures. Meteorological sensing is limited mainly by

the inaccuracy in measuring humidity which, under ideal conditions, appears to

limit the accuracy to + 1. N. Gradient measurements utilizing radiosondes re- flects an accuracy no better than + 3 N units. Radio frequency refractometers are capable of accuracies as much as an order of magnitude better than that achieved

by meteorological sensors. Lightweight refractometers have been devised for balloon-borne and dropsonde measurements reflecting accuracies inferior to the conventional refractometer but superior to the radiosonde. --Author's abstract.

E-930 Maenhout, A. G. , Quelques donnees sur le radioclimat d'Uccle . (Some data on

the radio climate of Uccle. ) Ciel et Terre, Brussels, 78(11/12) :391-396, Nov./

Dec. 1962. 2 figs. , 4 tables, 5 refs. DWB, DLC--The propagation of radio waves

with frequencies of more than 30 Mc/s and influenced by the thermodynamic conditions of the atmosphere are dealt with. The knowledge of this propagation depends

on some physical properties of the medium within which the waves propagate and

especially on the refractive index. Three tables give the mean values of the re- fractive index at surface and at a few standard levels. These mean values were computed on the basis of observations made from Jan. 1, 1956 to Dec. 31, 1960

at the Royal Met. Inst, in Uccle. The author points out that the radio waves

undergo a deflection due to decrease of the refractive index with height and emphasizes the importance of this deflection for very high frequency radio communication as well as in the field of space communication. (Met. Abs. 14. 9-174)

--A.V.

E-931 Maheshwari, R.C. (Met. Office, New Delhi), Radio refractive index structure over northern India and its synoptic variation. Indian Journal of Meteorology and

Geophysics, Delhi, 13(l):57-62, Jan. 1962. 6 figs. , 5 refs. , 3 eqs. DWB.DLC--

Synoptic distribution of the radio refractive index over northern India and its variation in association with some winter systems have been studied. Analysis of one

particular system is presented here. It is noted that the refractive index shows a systematic variation with the passage of the systems and can be utilized as a synoptic parameter. Mean sea level chart of refractive index and its distribution on standard isobaric surfaces might probably be used for forecasting at least qualitatively, the conditions of VHF propagation over northern India. (Met. Abs.

14. 3-160) -Author's abstract.

E-932 Marshall, J.S. (McGill Univ. , Montreal), Precipitation . International Scientific

Radio Union. Commission II on Radio and Troposphere, Monograph on radio wave

propagation in the troposphere: Proceedings of the Commission, 13th General

Assembly of URSI, London, 1960. Amsterdam, Elsevier Pub. Co. , 1962. p. 77-90.

7 figs. , 13 refs. English and French summaries p. 77. DLC (QC973. 1575), DWB

(M10. 62 I61mo)--Heavy rain can contribute a significant fast fading term to trans- horizon scattering. The pattern of rain-shower intensities can be studied by radar

at wavelengths from 10 down to 6 cm; at 3. 2 cm intensity values are seriously

diminished by attenuation by the rain itself. There would be great use for any

sensing device that would reveal cloud as radar reveals precipitation. Millimetric

receivers used to measure sky temperature are sensitive to cloud; their potentiality

for cloud measurements should be explored and exploited. --Author's abstract.
235

E-933 Medhurst, R.G. (Gen. Elec. Co. , Ltd. .Telecommunications Res. Lab. .Hirst Res.

Centre, Wembley, England), Distortion problems in f . m. multi-channel communication . Institution of Electrical Engineers, Journal, 8(92):384-386, Aug. 1962. 4 figs.

DLC--This article is based on a lecture at the Nov. 6, 1962 meeting of the Electronics and Communications Section at Savoy Place. Noise and distortion problems en- countered in frequency division multiplex (f. d. m.) long distance telephony and

transmissions of TV and radio, using the "baseband" frequency region, are discussed in terms of the white noise test signal. Formulation of reliable theoretical

techniques, some of which are demonstrated here, are requisite in lieu of the too

costly prototype systems for experimental purposes. --W. N.

E-934 Men', A.V. , O korreliatsii amplitudnvkh i fazovykh fluktuatsu radiovoln. ras - prostraniaiushchikhsia v troposfere. (On the correlation of amplitude and phase

fluctuations of radio waves propagated in the troposphere. ) Radiotekhnika i Elektronika, Moscow, 7(2):232-238, Feb. 1962. 3 figs. , 12 refs. , 11 eqs. Transl.

into English in Radio Engineering and Electronic Physics, N. Y. , No. 2:215-221,

Feb. 1962. DLC--The correlation between amplitude and phase fluctuations are examined, at the same point in space, which arise during propagation of waves

above a flat interface in an inhomogeneous turbulent medium. It is shown that

the theoretical results concerning the lack of correlation of these fluctuations in a distant region, which Chernov obtained under the assumption of an unlimited

medium, hold also for the present case. Results of experimental measurements

of the correlation of amplitude and phase fluctuations during propagation in lower

tropospheric layers are presented for both the illuminated region and the region

obscured by the curvature of the Earth's surface. --Transl. of author's abstract.

E-935 Men', A.V., O vliianii effekta perenosa neodnorodnostei v prostranstve na

fluktuatsii radiovoln v turbulentnoi' srede. (On the influence of the effect of

transfer of inhomogeneities in space on radio wave fluctuation in a turbulent medium. ) Radiotekhnika i Elektronika, Moscow, 7(3):369-374, March 1962. 4 figs.,

11 refs. , 5 eqs. Transl. into English in Radio Engineering and Electronic Physics,

N. Y. , No. 3:345-351, March 1962. DLC -The influence of the effect of transfer of

inhomogeneities on the fluctuation of radio waves propagated in the troposphere is

examined. Preliminary results of experimental investigations conducted in a distant zone are described. These results are in good qualitative agreement with

those derived by calculations. --Transl. of author's abstract.

E-936 Misme, P. (C.N.E.T. , Issy-les-Moulineux, Seine), Quelques aspects de la

radiometeoroloqie et de la radioclimatoloqie. (Some aspects of radiometeorology

and of radioclimatology. ) International Scientific Radio Union. Commission II on Radio and Troposphere, Monograph on radio wave propagation in the troposphere:

Proceedings of the Commission, 13th General Assembly of URSI, London, 1960.

Amsterdam, Elsevier Pub. Co. , 1962. p. 169-186. Figs., 11 refs. French and

English summaries p. 169. DLC (QC973. 1575), DWB (M 10. 62 I61mo) -The author

considers the following topics: the layer structure of the atmosphere, refraction,

and the fundamentals of radioclimatology. Initially it is shown that the work done

in France and in the United Kingdom proves that the atmosphere must be considered

as a turbulent medium within which exist permanently some stable thin layers.

Orders of magnitude of the latter are given. For refraction, consideration is given

to the difficulties in the choice of a parameter to represent the phenomenon: refractive index or gradient of refractive index. The author indicates the importance of

the equivalent gradient. Finally, in radioclimatology, the role of parameters of

atmospheric stability, as well as those of refraction, is discussed. --Author's abstract.
236

E-937 Naito, K. (Meteorological Res. Inst. .Tokyo), Some statistical considerations on

transhorizon propagations of microwaves -- with application to radio meteorology.

Pt. 1. Papers in Meteorology and Geophysics, Tokyo, 13(3/4): 207-215, Dec.

1962. 3 figs. , 8 refs. , 24 eqs. English summary p. 207; Japanese summary

p. 215. DWB--Since sampling time of actual analysis or recording period of observation is of finite length, statistical values obtained are sample means,

sample variances and so on, and not ones computed with the use of data over all members of the ensemble. Taking this fact into consideration, the received fields

in transhorizon propagation of microwaves are found to present, for a short sampling time, apparent coherency, which explains the results of WATERMAN'S rapid

beam swinging experiments. Furthermore, a method is presented to determine

whether or not only radio scattering due to atmospheric eddies is dominant in

transhorizon propagation. Actual analyses seem to show that, in most cases,

not only scatterings due to eddies but reflections due to wavy layers are dominant in over sea transhorizon propagation of 3000 Mc/s and 1300 Mc/s, apart from

other possible mechanisms which may be relevant to the propagations. In a few cases obtained in a well mixed atmosphere, the most dominant seemed to be eddy

scatterings. It may also be suggested that the sort of analyses made here would

be useful in affording some measure of weather situation on the so-called mesoscale. --Author's abstract.

E-938 Nekrasov, L.B. , K voprosu o prichinakh obrazovaniia radioekho diskretnokogerentnogo tipa. (Causes for the formation of radar echoes of a discrete coherent type. ) Leningrad. Glavnaia Geofizicheskaia Observatoriia, Trudy, No. 128:

77-83, 1962. 7 figs. , 3 refs. Russian summary p. 77. DWB, DLC--Radio echoes

from a cloudless sky are discussed, as well as meteorological conditions favoring

the radio echo formation of a discrete coherent type. Aerological data are presented and conclusions are drawn on the relation of the radio echoes to thermal convection in lower atmospheric layers. --Transl. of author's abstract-S. N.

E-939 Norton, K.A. ; Barrows, E.C.etal. , Variance of radio frequency caused by at- mospheric turbulence in line-of-sight transmissions. IRE Transactions on Instru- mentation, N. Y. , 1-2(3/4): 153-155, Dec. 1962. 4 figs. , 5 refs. , 5 eqs. DBS--

The frequency stability of a radio signal propagated over a line of sight path is

reduced by time variations in phase velocity along the path. This instability

caused by the atmosphere will produce errors in frequency measurements made by

averaging a standard frequency transmission over a period of time, T, and also

in time interval measurements made by counting the number of cycles of the standard frequency received during a period of time, T. Recent measurements of the

variations in phase of a received signal at microwave frequencies permit estimation of both types of error as a function of T. These atmosphere induced errors are compared to the errors inherent in the best currently available crystal oscillators and it appears that the latter source of error is dominant for line in sight

path through the atmosphere. The level and slope of the frequency spectra have

been observed to vary over wide ranges with time and geographic location. The

spectral formW (f)~f " 2'3 expected on the basis of the Obukhov-Kolmogorov

theory of atmospheric turbulence has a slope which lies well within the range of

observed slopes for the range of fluctuation frequencies from 1 cycle/day to 1 cps.

--Authors' abstract.
237

E-940 Raghavan, S.and Soundararajan, K. (both, Regional Meteor. Centre, Madras),

Study of abnormal radar propagation around Madras. Indian Journal of Meteorology

and Geophysics, Delhi, 13(4): 501 -509, Oct. 1962. 5 figs. , 3 tables, 4 refs.

DWB, DLC--Occurrence of supernormal radar propagation in the 3 cm band around

Madras has been investigated. The results generally agree with the findings of

DURST (1946). The temperature and humidity distribution giving rise to favorable

refractive index gradients in the various seasons and the wind distribution and

synoptic features aiding the setting of superrefraction are discussed. The occur- rence of superrefraction prior to formation of mist or fog has also been discussed

in relation to its forecasting value. --Authors' abstract.

E-941 Rider, G.C., Median signal level prediction for tropospheric scatter. Marconi

Review, London, 25C146): 203-210, Third Quarter 1962. 5 figs. , table, 10 refs.

DBS -Data from the BROMLEY-CATTERICK experimental link have been further

analyzed to give a regression line of refractive index upon path attenuation. A

slope of 0. 43 db per N unit is found, and this is shown to be in agreement with

GRAY's results for some Caribbean paths, (Elec. Comm. Vol. 36, p. 60, 1959).

GRAY's propagation curves for 900 Mc/s are shown to give good predictions,

very simply, for seven paths in widely differing climatic regions. For other fre- quencies and for difficult paths, it suggested that the new regression coefficient

be used in NORTON'S classical prediction formula. --Author's abstract.

E-942 Robinson, G. D. (Meteorological Office, London), Physical characteristics of

the troposphere. International Scientific Radio Union. Commission II on Radio

and Troposphere, Monograph on radio wave propagation in the troposphere: Pro- ceedings of the Commission, 13th General Assembly of URSI. London, 1960.

Amsterdam, Elsevier Pub. Co. , 1962. p. 65-76. 4 figs. , 2 tables, 10 refs. English and French summaries p. 65. DLC (QC973.I575), DWB (M1Q. 62 I61mo)--

Statistics are given of the occurrence of temperature inversions over England,

and the structure of some examples, as revealed by aircraft -borne thermometers,

hygrometers, and radio refractometers, is exhibited. Attention is called to the

work of Danielsen on the continental scale of layered structures. Some recent

analyses of frontal structures by Sawyer and others, display considerable divergence from the classical model, and an unexpected humidity pattern. The spectrum of atmospheric turbulence at heights of 1000-2000 ft, as revealed by results

of CRANE and CHILTON and recently by those of Smith, is discussed and the adequacy of some theoretical and empirical formulas examined. (Met. Abs. 15. 2-325)

--Author's abstract.

E-943 Ryzhov, lu. A. , O vzaimoi' funktsii korreliatsii fluktuatsu amplitudy i fazi volny,

rasprostraniaiushchefrsia v neodnorodnoi srede . (Cross correlation function of

fluctuations in amplitude and phase of a wave propagated in an inhomogeneous

medium.) Radiotekhnika i Elektronika, Moscow, 7(10): 1824-1825, Oct. 1962.

2 refs. , 13 eqs. Transl. into English in Radio Engineering and Electronic Physics,

N. Y. , No. 10:1686-1688, Oct. 1962. DLC, DBS -Formulas are given for the cross

correlation of fluctuations of level and phase of a plane wave in the case of a locally uniform and isotropic turbulence. --G.T.
238

E-944 Saxton, J. A. (Dept. of Sci. and Indus. Res. Radio Research Station (U. K. )), Some long distance tropospheric propagation studies in the United Kingdom. Inter- national Scientific Radio Union. Commission II on Radio and Troposphere, Monograph on radio wave propagation in the troposphere: Proceedings of the Commission,

13th General Assembly of U. R.S.I. , London, 1960. Amsterdam, Elsevier Pub. Co.,

1962. p. 28-38. 9 refs. English and French summaries p. 28. DLC (QC973.I575),

DWB (M10. 62 I61mo)--After a brief description of the development of tropospheric

propagation studies, with emphasis on transmission to points well beyond the hori- zon, the nature of tropospheric scatter propagation problem is discussed. A survey

is then made of recent British experimental contributions to this subject, covering

investigations at frequencies in the range 50 to 10, 000 Mc/s and over distances of

100 to 800 km. No simple model of the troposphere is likely to account for the vari- ous observed characteristics of scatter signals, and it is evident that a much more

exhaustive examination of the fine structure of the refractive index of the troposphere is required. (Met. Abs. 14. 9-175)--Author's abstract.

// E-945 Schunemann, R. and Pucher, G. , Uber eine Deutung der UKW Ausbreitunq in der

troposphere nach untersuchunqen der amplituden variationen bei 10 cm Wellenlange. (An explanation of VHF propagation in the troposphere from an investigation of amplitude variations of 10 cm waves. ) Hochfrequenztechnik und Elektroacustik, Leipzig, 71(l):34-40, Feb. 1962. DLC--The experiments conducted in

measuring field strength at 10 cm wavelength show in several instances, that only

20% of the temporary amplitude distribution corresponds to Rayleigh distribution,

and 80% of the readings had constant characteristics. It is concluded that the

partial reflections on the atmospheric layers play a considerable role in the long

distance propagation of the ultra short waves. --E.K.

E-946 Shaft, P. D. , Comparison of calculated and measured bandwidth of the Florida - Cuba tropospheric scatter system. IRE Transactions on Communications Systems,

N. Y. , 10(4):457-, Dec. 1962. Fig., table, 2 refs. DLC -The calculated distortion was greater than the measured, probably attributable to the propagation model

(i. e. , two paths defined by the extremities of the common scatter volume). The

results are valid for information bandwidths < 4. 2 Mc/s. --W. N.

E-947 Sichak, W. and Adams, R.T. , Intermodulation noise in FM troposcatter links.

Institute of Radio Engineers, Proceedings, N. Y. , 50(10):2113, Oct. 1962. Fig.,

table, 5 refs. , 5 eqs. DLC --The purpose of this note is to give an approximate

formula for the intermodulation noise produced by tropospheric scattering. The

measured and calculated values of the signal to intermodulation ratio are shown

in a figure. --E. K.

E-948 Straiton, A. W. ; Deam, A. P. and Walker, G. B. , Spectra of radio refractive index

between ground level and 5000 ft above ground. IRE Transactions on Antennas and

Propagation, N. Y. , 10(6) -.732-737, Nov. 1962. 9 figs. , table, 8 refs. DLCAtmospheric index of refraction has been measured from ground level to 5000 ft using the Deam telemetering refractometer which permitted accurate spectral analysis of these data. The results of the analysis show a wide variation in the mean

slope and intensity of the spectra. Some of the spectra are presented and their

characteristics discussed. --Authors' abstract.
239

E-949 Tatarskii, V.I. , Vtoroe priblizhenie v zadache o rasprostranenii voln v srede so sluchainymi neodnorodnostiami. (Second approximation in the problem of wave

propagation in media with random inhomogeneities. ) U.S.S.R. Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia Vysshikh Uchebnykh

Zavedenii, Radiofizika, 5(3):490-507, 1962. 11 refs. , 102 eqs. English summary

p. 507. DLC--A second approximation to the smooth perturbation method is considered and applied to solving the problem of short wave propagation in media with

random inhomogeneities. Second order corrections to mean values, spectra and

correlation functions of wave amplitude and phase are determined in small nonlinear terms. On the basis of these solutions the limits of validity of the "smooth

perturbation method" are investigated. --Author's abstract.

E-950 Tatarskil*, V.I. and Golitsyn, G.S., O rasseianii elektromagnitnykh voln turbulentnvmi neodnorodnostiami troposfery. (Electromagnetic wave scattering by tur- bulent inhomogeneities of the troposphere.) Akademiia Nauk SSSR. Institut Fiziki

Atmosfery, Trudy, No. 4:147-202, 1962. 15 figs. , 52 refs. , numerous eqs. DLC.

Transl. into English in corresponding issue of its Transactions, issued Consultants

Bureau, N. Y. DLC--The authors attempt to present from a general point of view

the theory of scattering of radio waves in the troposphere. Particular attention is devoted to an overall physical interpretation of the mechanism of scattering of

radio waves by random inhomogeneities. The contents of this comprehensive

study include the following: the initial equations, that is, the Maxwell equations

and their solution; the scattering field in the zone of Fraunhofer diffraction; the

representation of a scattering field by the spectrum of the refractive index; Brogg's

statistical formula; scattering on random inhomogeneities in the approximate

Fresnel diffraction; the microstructure of fluctuations of dielectric permeability in a turbulent atmosphere; computation of the mean scattering power for real tracks;

correlation function of the scattering field; statistical properties of the scattering

field; and scattering of an impulse. (Met. Abs. 14. 9-176) --I.L. D.

E-951 Tohsha, M. (Met. Res. Inst. , Tokyo), On the regional distributions of radio meteor- ological elements in the one kilometer layer. Papers in Meteorology and Geophysics, Tokyo, 13(2): 163-170, Sept. 1962. 4 tables, 5 refs. , 7 eqs. English sum- mary p. 163. Russian and Japanese summaries p. 169-170. DWB--Some local characteristics of the refractive index which are needed for the research of microwave

propagation are described in a general way. The refractive indices on the surface

and at 900 mb level are calculated with the use of the aerological sounding data.

The vertical gradient of the refractive index is obtained by the use of these values.

The local values of the refractive index decrease toward north. The maximum val- ues are located on about 30° zone of north latitude. On the open sea and at the

end of the peninsulas, the vertical gradients of the refractive index have comparatively large values. In the cold season, the gradient values on inland are larger

than ones of the coastal stations, and in the warm season, the above mentioned

situation is the opposite. With the exception of Hokkaido Island, the values of

effective earth which is used in the theory of radio wave propagation are larger

than the value got by the assumption of the standard atmosphere. (Met. Abs.

14. 11-115) -Author's abstract.
240

E-952 Tremblay, R. , Etude theorique et experimental e des problemes de fluctuations

rapides en propagation tropospherique . (Theoretical and experimental study of

the problems of rapid fluctuations in tropospheric propagation. ) Annales de

Radioelectricite', Paris, 17(70): 280-296, Oct. 1962. 13 figs. , 6 tables, 20 refs. , 68 eqs. DBS--This study concerns the problem of rapid fluctuation of the received

signal in tropospheric transmission. An analysis of signal fluctuations as a function of time shows the correlation between fluctuation and the transverse component of upper air wind. A great similarity is found between the amplitude frequency

and the amplitude time spectra, except when the fluctuations in time are caused

by atmospheric turbulence. An elaborate experimental study (Cholet-Orsay path,

3300 Mc) confirms the theoretical results. Data obtained in the experiment are presented. --From author's abstract.

E-953 Vergara, W. C. ; Levatich, J.L.and Carroll, T.J. , VHF air-to-ground propagation

far beyond the horizon and tropospheric stability. IRE Transactions on Antennas

and Propagation, N. Y. , 10(5) -.608-621, Sept. 1962. 19 figs. , table, 39 refs.

DLC--The results of twilight region propagation experiments on 128 Mc/s over the

air line route San Francisco, Calif. - Honolulu, Hawaii are presented and discussed. The results include the largest air-to-ground VHF measurements known

to exist. Mechanism of minimum twilight propagation is explained in terms of

wave mode due to partial reflections in a gravitationally stratified atmosphere.

The significance of the height of the antenna over the ground is demonstrated.

VHF air-to-ground propagation is extendable everywhere and at all times, to at least twice the horizon range. --W. N.

E-954 Wait, James R. (Nat'l. Bur. of Standards, Boulder, Colo.), Note on the propagation of electromagnetic pulses over the Earth's surface . Canadian Journal of

Physics, Ottawa, 40(9) -.1264-1269, Sept. 1962. Fig., 15 refs. , 12 eqs. DWB,

DLC--A note considering the propagation of electromagnetic pulses over the

Earth's surface first refers to the classic work of VAN DER POL (1956) and others

including the author's previous work, then shows how the Sommerfeld (1926) form

of the attenuation function is applicable to pulse propagation over a flat Earth

provided the dielectric constant is reasonably large compared with unity. On the

basis of the present calculations, the form of the numerical distance V~sq as suggested by NORTON (1937) appears to lead to more accurate results. --E. Z. S.

E-955 Wait, J. R. , Wave propagation around a curved boundary which contains an obstacle. Canadian Journal of Physics, Ottawa, 40(8): 1010-1016, Aug. 1962. 13

refs. , 32 eqs. DWB, DLC--The problem is to calculate the field of an electric

dipole on a smooth spherical or cylindrical surface which contains a localized

obstruction. An approximate solution is obtained by combining the rigorous theory

of diffraction by a sphere and the approximate Kirchoff diffraction theory for black

screens. The application to ground wave propagation is briefly indicated. (Met.

Abs. 14. 3-162) -Author's abstract.

E-956 Walters, Lillie C. and Johler, J.Ralph (both, Nat'l. Bur. of Stands. .Boulder, Colo. ), Diffraction of spherical radio waves by a finitely conducting spherical Earth. U.S.

National Bureau of Standards, Journal of Research, Sec. D, 66(1): 101-106, Jan./

Feb. 1962. 7 figs. , 15 refs. , 41 eqs. DWB, DLC -The theory for the diffraction

of spherical electromagnetic waves by a finitely conducting spherical Earth was

developed from Maxwell's equations by WATSON (1918) and the intricate computation details were later worked out by VAN DER POL and BREMMER (1936) as

the now classical series of residues. Two aspects of this computation present
241

considerable difficulty, especially at low frequencies: (1) The calculation of the

height gain factor which takes account of an elevated transmitter and/or receiver.

(2) The evaluation of the special roots, T= Js of Riccati's differential equation,

- 2 S •7+1=0 near the circle of convergence,! S * ' = 1/2. These Sr

analytic difficulties are avoided with the aid of modern analysis techniques applied to a large scale electronic computer. Hankel functions of the first and sec- ond kind of order one-third and two-thirds are calculated by numerical integral

methods and then used with iteration to solve Riccati's differential equation. The

amplitude and phase of the spherical radio wave diffracted in the vicinity of the

Earth with various altitudes above the surface of the Earth, of both the transmitter

and the receiver, are then calculated by a summation of the series of residues.

(Met. Abs. 14.4-122).-Authors' abstract.

Wilkerson, Robert E. , Defocusing of radio rays by the troposphere . U.S. National

Bureau of Standards, Journal of Research, Sec. D, 66(4): 479-485, July/Aug. 1962.

5 figs. , table, 8 refs. , eqs. DWB, DLC--When radio rays pass through the atmosphere, they are defocused due to its presence. This effect is measured by the

divergence coefficient and general formulas are derived for Dj.the divergence coefficient of the direct ray, and D2, the divergence coefficient of the reflected ray —

assuming a smooth spherical earth. As examples, Dj and Do are shown for some

typical cases with an " exponential " atmosphere (troposphere). (Met. Abs.

14. 3-163) --Author's abstract.

Wolf, James M. , Radar ring "angels". Symposium on Remote Sensing of Environment, 1st, Univ. of Michigan, Feb. 1962, Proceedings. Ann Arbor, March 1962.

p. 57-60. 8 refs. DWB (M(051) S989p 1962)-" Angels" the false echoes picked up

by the more powerful and more sensitive radars have been believed to be due to irregularities in the atmosphere. This short paper describes a peculiar angel in

the form of an expanding ring observed in the summer of 1955 about 10 mi S of the

radar site at Willow Run Airport. A film of this angel presented at the Symposium

is discussed. A published analysis of the film with accompanying meteorological

data showed that the rings were seen under a great diversity of weather conditions.

It was found that, as in Texas and in England, the rings were produced by the

birds leaving their roosts. The author states that the study of bird movements by

radar has become a part of ornithology. (Met. Abs. 14. 6-828) --D.B. K.

Wright, F.Edward (U.S. Navy), The effect of neglecting horizontal variations in

refractivitv. 1962. Thesis (Ms.Sci. in Met. ) - U.S. Naval Postgraduate School,

Monterey, Calif. 26 p. 4 figs. , 3 tables, 3 refs. , 28 eqs. DWB-Atmospheric

models which depict the vertical distribution of refractivity in exponential form

are commonly used when tracing high frequency radio ray paths. To date, in the

determination of ray paths using these models, one generally neglects horizontal

variations of refractivity and the implied variation of vertical gradient of refractivity along the ray path. The effects of these simplifications are investigated,

using a regional exponential model based upon radio climatology compiled by

BEAN and THAYER. An accurate method for ray path construction is devised,

and it is found that the horizontal gradient of refractivity of the model has little effect upon the ray path to horizontal distances of 400 mi. However, a variation

in the horizontal gradient is associated with a much larger horizontal variation of

the vertical gradient, which does significantly affect the ray path. (Met. Abs.

14. 10- 100) -Author's abstract.
242

1963

E-960 Anderson, J. Bach, Reception of skywave signals near a coastline . U.S. National

Bureau of Standards, Journal of Research, Sec. D, 67(3): 325-330, May/June 1963.

3 figs. , 8 refs. , numerous eqs. DWB, DLC--An experimental investigation has

been made on the influence of ground inhomogeneities on the reception of skywave

signals, especially the influence of the conductivity contrast near a coastline.

This gives rise to a rapid decrease in field strength near the coastline as is well

known from ground wave mixed path theory. Comparison with theory is given.

Influence of diffuse reflection from the ionosphere is also considered. --Author's

abstract.

E-961 Anway, Alan C. , Empirical determination of total atmospheric refraction at centimeter wavelengths by radiometric means . U.S. National Bureau of Standards,

Journal of Research, Sec. D, 67(2): 153-160, March/April 1963. 9 figs., table,

9 refs. , 3 eqs. DWB, DLC--The experimental procedures and data analysis methods used in the determination of total atmospheric refraction by radiometric means

are described. The results of 5 months' observations are presented in plots of

the mean refraction, its standard deviation, and standard error of estimate for

specified altitude angles between 2 and 65 degrees. The a.m. values of refraction are significantly greater than those of the p. m. at the same altitude angle.

This effect is attributed to the diurnal cycle. The measured total refraction exhibits a strong linear correlation with surface refractivity. --Author's abstract.

E-962 Arendt, P. R. and Soicher, H. (both, U.S. Army Electronic Res. and Dev. Lab. , Fort Monmouth, N. J. ), Radio horizon distribution variation on 108 megacycles

per second measured with satellite signals. Journal of Geophysical Research,

Wash. ,D.C, 68(4): 1039-1049, Feb. 15, 1963. 5 figs. , table, 7 refs. DWB,

DLC--The radio horizon of satellite signals for an observer on Earth is measured

with a satellite of 780 km average altitude and a beacon frequency of 108 Mo/s.

The analyzed data consist of measurements from 295 orbits from July 13, 1961 to Dec. 4, 1961. The statistical distribution of radio horizon data differs considerably from the geometric horizon and from the radio horizon calculated to allow

for refraction effects using an equivalent radius of 4/3 the Earth's radius. The

observed radio horizon depends on seasonal changes as well as on the topographical regions along which the radio waves travel when the satellite is at low

elevation. During summer the data are sporadic, in contrast to fall and winter

when the data are more uniform. The either sporadic or uniform nature of the data

is ascribed to the seasonal variation of the ionosphere. However, whereas the

average radio horizon along sea is at all times longer than the corresponding geometric horizon by approximately 300 mi, the one along land was always found to be considerably shorter during the summer and late fall and only slightly longer

during the winter. The lengthening along sea goes beyond the radio horizon calculated with 4/3 the Earth's radius. It is suggested that a tropospheric duct,

facilitated by the Gulf stream near the station and greater abundance of water

vapor above the sea, is responsible for lengthening the radio horizon along the

sea. (Met. Abs. 14. 9-162) -Authors' abstract.

E-963 Atkinson, Neal W. , Evaluation of automatic Picture Transmission Ground Station

(APTGS) for army mobile use. U.S. Army Electronic Research and Development

Labs., Ft. Monmouth, N. J. , Technical Report, 2396, Oct. 1963. 10 p. 2 figs.,

2 refs. DWB (M(055) U5812te)»This report is an evaluation of an Automatic

Picture Transmission Ground Station (APTGS), as developed by the National Aeronautics and Space Administration, designed to provide facsimile reproductions of
243

local cloud cover pictures transmitted from an orbiting Nimbus satellite. An analysis of this system is presented, outlining the problems and recommended solutions

of using this basic system design to create an experimental mobile version of the

APTGS suitable for Army field type applications. --Author's abstract.

Barghausen, A.F. ; Guiraud, F. O. ; McGavin, R.E. etal. , Equipment characteris - tics and their relation to system performance for tropospheric communication circuits , U.S. National Bureau of Standards, Technical Note, No. 103, Jan. 15, 1963. p. 173.

52 figs. , 4 tables, bibliog. p. 169-173. 68 eqs. DLC--The performance of a tropospheric communication system, either within the limit of sight or beyond the line of

sight, is directly dependent on the operating characteristics of the equipment. Per- formance predictions of a communication system are made on the basis that equipment will operate in a prescribed manner. The degree of success of the communications system will depend largely upon how well these predicted values correspond

to the actual operating values. Consideration is given to those portions of the

equipment that have definite effect upon the operating performance. Specific items

of equipment and methods for determining their performance are considered. Representative results in light of the present state of the art permits an evaluation of an

actual system in terms of realizing an optimum system. In systems that do not

have the optimum characteristics desired consideration is given to laboratory devices which may alleviate these deficiencies. Future systems should consider in- corporating these devices as development permits. --Authors' abstract.

Barsis, A. P. ; Barghausen, A.F. and Kirby, R.S., Studies of within-the-horizon

propagation at 9300 Mc. IEEE Transactions on Antennas and Propagation, 11(1):

24-38, Jan. 1963. 15 figs. , 4 tables, 14 refs. , 8 eqs. DLC --Propagation characteristics of radio signals over a 113 km tropospheric path in Eastern Colorado was

investigated with stress on the short term fading characteristics. Sampling the

9250 and 9350 Mc instantaneous carrier amplitude at the rate of one per second,

0. 91 was the over all cross correlation coefficient. Expressed in db, the standard

deviation averaged 0. 76 db, maximum hourly 1.81 db. --From authors' abstract.

Bass, F. G. and Verbitskii, I.L. , O chastotnom spektre elektromaqnitnykh voln.

rasseiannykh statisticheski nerovnoi poverkhnost'iu. (Frequency spectrum of

electromagnetic waves scattered by a statistically rough surface.) U.S.S.R.

Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenii, Radiofizika, 6(2):290-296, 1963. 7 refs. , 25 eqs.

English summary p. 296. DLC --Expressions are given for various tensors of the

electromagnetic field scattered by a statistically rough surface, taking into ac- count curvature and finite conductivity of the average surface. The effect of dissipative processes upon the spectral line width of the scattered field is considered

and corrections to the spectral density of the field are obtained in the second approximation of the theory of perturbations. --Authors' abstract.

Beach, CD. and Trecker, J. M. , A method for predicting inter-channel modulation

due to multi path propagation in FM and PM tropospheric radio systems . Bell System Technical Journal, N. Y. , 42(l):l-36, Jan. 1963. --This paper describes a method for predicting the magnitude of interchannel modulation due to multipath propagation on angle modulated tropospheric scatter radio systems. Values of signal

to intermodulation ratio, S/I, are calculated for various pairs of signal reflections

in the troposphere, taking into account the base bandwidth and frequency deviation

of the system, the antenna patterns, the path geometry, and climatic conditions

during the worst month of propagation. The lowest value of S/I (worst inter-modulation) computed for such pairs of signal reflections is then corrected empirically to
244

account for multiple reflections. The result represents the median value of S/I

expected during the worst month of transmission on a specified path. The method

yields results that, when compared to measured results from four widely different

path normalized to worst month conditions, have a standard error of estimate of

about 2.6 db. --Authors' abstract.

E-968 Bean, B. R. ; Dutton, E. J. ; Lane, J. A.etal. (all, Nat'l. Bur. Standards, Boulder),

Radiometeoroloaical study. Pt. 3. A new turbulence parameter. U.S. National

Bureau of Standards, Journal of Research, Sec. D, 67(6):605-608, Nov. /Dec. 1963.

Table, 4 refs. , 20 eqs. (For Pt. 1, see E-996; for Pt. 2, see E-969). DWB, DLC--

The concept of thermal stability is utilized to derive expressions for the radio re- fractivity of an air parcel undergoing adiabatic compression or expansion. These

expressions are of exponential form with scale heights of 12. 5 km for the dry

adiabatic process and 7. km for the wet adiabatic process. The adiabatic curves

for N are determined solely from conditions at the Earth's surface. A new turbulence parameter, II, is derived as the difference of the environmental refractive

index structure and the adiabatic curves for an air parcel lifted from the surface

to 3 km. This parameter yields correlations with 3 hourly median field strength

data that are not statistically different from those obtained with the much simpler

parameter,^. N. The correlations obtained with the equivalent gradient are not

statistically different from zero. --Authors' abstract.

E-969 Bean, B.R.; Frank, V.R. and Lane, J. A. (all, Nat'l. Bur. Standards, Boulder),

Radiometeorological study. Pt. 2, An analysis of VHF field strength variations

and refractive index profiles. U.S. National Bureau of Standards, Journal of Research, Sec. D, 67(6): 597-604, Nov. /Dec. 1963. 7 figs. , 3 tables, 17 refs. , 7 eqs. (For Pt. 1, see E-996; for Pt. 3, see E-968) DWB, DLC--This paper dis- cusses the cumulative probability distributions of field strength for four 200 km

VHF paths in Illinois in terms of a classification of refractive index profiles. It is shown that extended elevated layers produce signal enhancements of 10 to 25

db above the level observed in unstratified conditions. Assuming the layer characteristics given by radiosonde data, the best agreement between calculated and

measured values of field strength is obtained using a layer model with a linear n profile. The possible influence of smaller layers is also discussed in relation

to the observed results for conditions judged to be unstratified or well mixed on

the basis of sonde data. --Authors' abstract.

E-970 Bean, B. R.and Thayer, G. D. , Comparison of observed atmospheric radio refraction effects with values predicted through the use of surface weather observations.

U.S. National Bureau of Standards, Journal of Research, Sec. D, 67(3): 273-285,

May/June 1963. 12 figs. , 3 tables, 14 refs. , 3 foot-notes, 15 eqs. DWB, DLC--

Past theoretical work has shown that it should be possible to estimate the atmospheric refraction of radio waves quite accurately simply from a knowledge of the

radio refractive index at the surface of the Earth. Prediction equations have been

developed for use in estimating both elevation angle errors and radio range errors by means of performing linear regressions of ray traced refraction variables on the

values of surface refractivity, Ns , for a standard sample of radio refractivity profiles. In this paper the accuracy of these prediction equations is examined through

a comparison with some precise measurements of total absolute refraction made

with a radio sextant by the Collins Radio Co. , some absolute elevation angle error measurements made at White Sands Missile Range in the lower atmosphere, and

measurements of both relative elevation angle error and relative range and range

difference errors made over various paths in the lower atmosphere. The validity of

the refractive index profile sample use.d is confirmed through a test on some
245

independent data obtained from four locations well outside the area of selection of

the original sample. All results are shown to be consistent with the theoretical

prediction model. (Met. Abs. 14. 11-110) --Authors' abstract.

Bolgiano, R.,Jr. (Cornell Univ. ), Evidence of anisotropy in tropospheric microstructure. Journal of Geophysical Research, Wash. , D.C. , 68(16) :4873-4874,

Aug. 15, 1963. Fig. , 11 refs. , 2 eqs. DWB, DLC-Reports a study of the spectral structure of refractive index in the troposphere by radio methods. Experimental results indicate varying degrees of anisotropy in the lower atmosphere during

summer days. The degree of anisotropy apparently varies from day to day, and

may, in some occasions, be negligible. --E.Z. S.

Boudouris, George (Univ. Paris), On the index of refraction of air, the absorption

and dispersion of centimeter waves by gases . Transl. from original French by G. Wm.

Curtis. U.S. National Bureau of Standards, Journal of Research, Sec. D, 67(6):

631-684, Nov. /Dec. 1963. 37 figs. , 8 tables, bibliog. p. 681-684, numerous eqs.

DWB, DLC--The index of refraction, the absorption and dispersion are studied for several gases and vapors (pressure from to 1 atm, temperature from to 50° C,

frequency from 7000 to 12,000 Mc/s). The first part is devoted to a description of

the microwave spectrometer used, while the second part is a survey of the several

theories implied in the interpretation of the results. In the third part, we present

first the results concerning the index of refraction of atmospheric gases, of dry air,

and of damp air. Then we study the absorption and dispersion by several vapors,

and of ammonia and chloroform, principally. Finally, a new method is indicated,

making use of gaseous mixtures. The original results are discussed and presented

within the frame of reference of works of other authors by means of comparison and

intensive bibliographies. --Author's abstract.

Bradshaw, John A. (Gen. Elec. Res.Lab. , Schenectady, N. Y.), Some implications

of aircraft interference patterns in troposcatter reception. U.S. National Bureau of

Standards, Journal of Research, Sec. D, 67(4) -.405-415, July/Aug. 1963. 17 figs.,

12 refs. , eqs. DWB, DLC --Aircraft interference patterns in troposcatter signal

records betray the plane's velocity across the link axis. The patterns also reveal

the phase variations in the normal signal path. Similarly, the spectra of records

free of aircraft patterns reveal the cross axis velocity of winds aloft. The amplitude distributions of such records often come close to the Rayleigh model but do

not follow weather parameters closely. The distributions of ratios and products of

correlated amplitudes also fit the Rayleigh model in records free of aircraft reflections. --Author's abstract.

Clarke, R.H. (Dept. of Electrical Engrg. , Univ. College, London), Measurements

on radiation reflected obliquely from a rouah surface. Institution of Electrical

Engineers, London, Proceedings, 110(11):1921-1927, Nov. 1963. 8 figs. , 2

tables, 7 refs. , 14 eqs. DLC --Experiments are described, and their results analyzed,' of the reflection (at oblique incidence) of microwaves of 8 mm wavelength

from a rippled water surface. The surface profile was, to a good approximation,

randomly rough, and a series of roughness states, extending from 'slightly rough"

to 'very rough' and whose statistical characteristics were known, were used. The

time variation of the amplitude and phase of the reflected radiation was observed

for the two principal polarizations of the incident radiation, as well as their co- variation when the incident radiation was polarized in a direction at 45° to the

plane of incidence. The results are discussed in terms of recently proposed

theories, and some encouraging agreement is found. --Author's abstract.
246

E-975 David, P. , Rappel de quelques qeneralites sur la propagation des ondes dans differents milieux. (Some generalities on wave propagation in different mediums.)

(In: NATO Advanced Study Institute, Corfu, Meteorological and astronomical influences on radio wave propagation. Ed. by Bjorn Landmark. N. Y. , Macmillan,

1963. p. 121-137. Fig., table, 34 eqs. English summary p. 121. ) DLC, DWB

(621.384 N864me) --Electromagnetic wave propagation in dielectric and ionized

mediums is treated. The treatment includes the effect of collisions, but is limited

to homogeneous and isotropic mediums. Formulas for dielectric constants, conductivities and refractive indexes, are derived. Different limiting cases are considered. Phenomena connected with passage from one medium to another is treated.

In an appendix some relations between phase velocity and group velocity are ex- plained. --Author's abstract.

E-976 David, P. and Voge, J., Role de la troposphere . (Role of the troposphere. ) (In:

NATO Advanced Study Institute, Corfu, Meteorological and astronomical influences on radio wave propagation. Ed. by Bjorn Landmark. N. Y. , Macmillan, 1963. p. 251-

279. 18 figs. , table, 13 refs. , 23 eqs. English summary p. 251. DLC, DWB

(621.384 N864me)--The relevant meteorological aspects are briefly reviewed. The

formulas for atmospheric refraction are deduced, and equivalent models for propagation calculations are given. The influence of the fine structure of the troposphere on the propagation over paths of different lengths is treated, ending with a discussion of tropospheric scatter communication. Finally, the importance of absorption

in the atmosphere is considered. --Authors' abstract.

E-977 Doherty, Lome H. (Nafl. Res. Council, Ottawa), Electrical conductivity of the

Great Lakes. U.S. National Bureau of Standards, Journal of Research, Sec. D,

67(6): 765-771, Nov. /Dec. 1963. 6 figs. , table, 10 refs. DWB, DLC -A critical

examination has been made of the electrical conductivity values assigned, for

radio propagation purposes, to the waters of the Great Lakes. Discrepancies between conductivity values measured in the laboratory and those deduced from field

strength measurements are shown to have been the result of both experimental error and the use of faulty standard theoretical field strength curves. The latter source

of error is the result of error in the standard curves themselves and in the use of a

dielectric constant of 15 for over water propagation. Conductivity values derived

from laboratory measurements of water samples are significantly different from

those published in conductivity maps. Large seasonal variations in conductivity,

approaching a factor of two in some cases, are a significant complicating factor.

--Author's abstract.

E-978 Drimmel, Julius (Vienna), Eine meteoroloqische Untersuchunq von Fernseh-Weitempfanq in Wien. (A meteorological investigation of distant television reception

in Vienna. ) Wetter und Leben, Vienna, 15(9/10): 196-198, 1963. 4 refs. German

and English summaries p. 196. DLC --The television reception over distances from

about 1000 to 2000 km in middle latitudes is examined from a meteorological viewpoint. It is found that the anomalous propagation of the television waves is combined in 80% with showery or thundery weather conditions between the transmitter

and receiver. This propagation anomaly in the field of ultrashort waves is caused

by reflection of the waves on the sporadic E layer. Therefore, the formation of

latter in middle latitudes is presumably released in many cases by showers and

thunderstorms in summer. --Author's abstract.
247

Franceschetti, Giorgio (Istituto Univ. Navale, Naples, Italy), An approach to tropospheric duct propagation. Institute of Electrical and Electronics Engineers,

N. Y. , Proceedings, 51(11): 1481-1486, Nov. 1963. 2 figs. , 12 foot-refs. , 29 eqs.

DLC--A model solution for the em propagation in a spherical stratified troposphere

is derived, via the Marcuvitz-Schwinger formalism. The approximations due to the

small curvature of the Earth are illustrated. The representation of the sources via

the complete set of model solutions is presented, as well as the excitation factors,

computed for the vertical electric or magnetic dipole. The possible use of digital

and analog computers is highlighted. Future plans for the work are the computations of a great deal of digital and analog solutions, and also the study of the in- fluence of the random variability of the tropospheric refraction index. In the Appendix, a preliminary case f(z) = az is presented. --Author's abstract.

Furutsu, K. , On the statistical theory of electromagnetic waves in a fluctuating

medium. Pt. 1. U.S. National Bureau of Standards, Journal of Research, Sec. D,

67(3): 303-323, May/June 1963. 9 figs. , 12 refs. , numerous eqs. DWB, DLC--

The subject of electromagnetic wave scattering by a randomly varying medium is

reviewed giving special emphasis to the technical method of approach. The symbolic representation of Maxwell's equations is introduced to make it easier to survey the whole subject and to formulate the equations. The Feynman diagram

method is applied to the computation of the correlation of the fields at different

points in space to any order of approximation. The differential equation to be

satisfied by the latter correlation function is also derived from another point of

view. Then the theory is developed on the "renormalization" of the constants,

i. e. , the effective propagation constant in a fluctuating medium and the effective

coupling constant between the field and the medium, etc. ; the explicit expression of the former is obtained to the first order of approximation. The dispersion

relation is derived as a connected problem. In Pt. II of this series of papers, a fundamental theory of statistics of the electromagnetic field \n a fluctuating me- dium will be developed. In Pt. Ill, a few applications to tropospheric scattering

will be given. --Author's abstract.

Furutsu, K. (Nat. Bur. of Stands. .Boulder, Colo. ), On the theory of radio wave

propagation over inhomogeneous Earth. U.S. National Bureau of Standards,

Journal of Research, Sec. D, 67(l):39-62, Jan. /Feb. 1963. 27 figs. , 19 refs. , 5 eqs. DWB, DLC--The formulas of field strength over an inhomogeneous spherical Earth are obtained on the conditions that (I) the radius and the electrical properties of the Earth's surface discontinuously change several times along the wave

path, or (II) the surface of terrain arbitrarily changes in height along the wave

path, but it is still smooth everywhere and the radius of curvature is sufficiently

large as compared with the wavelength. The case (I) is considered to be more

general than those of mixed paths on a smooth Earth, because the latter can be seen as special cases of the former. The case (II) corresponds to the case of

multiple diffraction of radio waves by several mountains having finite radii of

curvature. In both cases, the unified formulas of field strength are obtained in

the form of a multiple residue series, which is reduced to the ordinary Van der Pol

and Bremmer formula in the special case of homogeneous ground. The convergence

of series of the formulas is very good when the propagation distance on every section of the inhomogeneous ground is long enough or the diffraction loss is large

enough, and is poor when any one of these distances is so short that the section

is effectively seen as a flat plane, or the diffraction loss on the section is very

small. In these cases, the flat Earth or other approximations can be used, and

several supplementary formulas are prepared for cases of poor convergence.

Several special applications are given. --Author's abstract.
248

E-982 Gates, David M. ; Vetter, M. J. and Thompson, Moody C. (all, National Bureau

of Standards, Boulder Labs. , Boulder, Colo. ) , Measurement of moisture boundary

layers and leaf transpiration with a microwave refractometer. Nature, London,

197(4872): 1070-1072, March 16, 1963. 3 figs. , 4 refs. DWB, DLC--The refractive index of air at microwave frequencies is determined chiefly by the air temperature, the total pressure and the partial pressure of the water vapor present.

The dependence of the index on the last quantity is sufficiently large that instruments (refractometers) which measure the index can be used to study variations

in water vapor pressure. A microwave refractometer is described here which is

shown to be extremely sensitive and responsive for the detection of the moisture

concentration within a boundary layer near a moist surface. The air must be

drawn very slowly into the refractometer. A hyperdermic needle was used as a probe in the experiments described. The boundary layer profile was measured

over a free water surface. The transpiration of leaves was observed while they were subjected to various stimuli of light and darkness. Changes in moisture

concentration amounting to a variation as little as 0. 1 percent relative humidity

(at 20° C) can be detected. By reducing the size of the microwave cavity (for

example, going to the K band rather than X band) it should be possible to reduce

the response time by about one order of magnitude and increase the sensitivity.

--R.B.

E-983 Goliashov, A.V. , O graficheskom opredelenii effektivnykh znachenil elektricheskikh parametrov pochvy trassy dlia ukv. (Graphical determination of the ef- fective electrical parameters of the ground along a USW communication link.)

Radiotekhnika i Elektronika, Moscow, 8(3):389-393, March 1963. 2 figs. , table, 3 refs. , 8 eqs. Transl. into English in Radio Engineering and Electronic

Physics, N. Y. , No. 3:341-345, 1963. DLC --A graphical method is proposed for

determining the effective dielectric constant and electrical conductivity of the

ground along a USW link. The basic quantity used in the method is the field

intensity, measured at different USW frequencies along the route and reduced

to the same radiated power and antenna gain (directivity). --Transl. of author's

abstract.

E-984 Gough, M. W. , The plane of polarization as a factor in VHF and UHF broadcasting . Marconi Review, Chelmsford, 26(149): 117-131, Second Quarter 1963. 6

figs. , 9 refs. , 12 eqs. DBS --The prevailing preference for the use of horizontal

polarization in the VHF and UHF bands, both in broadcasting systems and in

point-to-point links,has prompted a critical appraisal of the comsequences of

this policy from the propagation viewpoint. Attention is focused on those re- gions within the visual range where destructive interference between direct and

surface reflected waves may cause deep nulls wherein the field strength is much

below the desirable "free space" value. Consideration of representative frequencies in the broadcast bands I-V inclusive, shows that the use of vertical polarization, rather than horizontal, can confer a substantial increase in field strength

in the nulls (particularly for oversea paths), under practical conditions which are defined in the article. --Author's abstract.

E-985 Hargreaves, J. K. and Hargreaves, S. , Numerical approach to the solution of

radio diffraction problems. U.S. National Bureau of Standards, Journal of Research, Sec. D, 67(6): 685-698, Nov. /Dec. 1963. 18 figs. , 2 tables, 9 refs. , 10 eqs. --It is proposed that some diffraction problems can be conveniently solved

by a direct numerical integration of the Fresnel-Kirchhoff formula. The required

properties of the diffraction screen are represented by a series of numbers which

can be either regular and periodic, or partially random. The necessary limits
249

and integration intervals are considered, and the method is found to be convenient

for Fresnel diffraction and for irregularities not too large compared to the wavelength. Both deep and shallow modulation can be treated. The accuracy of the

computations is verified in a simple case of sinusoidal modulation, and some new

results are derived for random phase screens. --Authors' abstract.

Hartman, William J. (Nat'l. Bur. of Stds. .Boulder, Colo. ), Path antenna gain and

comments on "Properties of 400 Mcps long distance tropospheric circuits" . Insti- tute of Electrical and Electronics Engineers, N. Y. , Proceedings, 51(5): 847-848,

May 1963. 7 refs. DLC--In connection with Chisholm's paper (see E-894) the

author demonstrates by a practical example, how it does not hold that there be no

loss in path antenna gain applying an isotropic antenna only at one end of a tropospheric scatter path*. Furthermore, neither by theory nor by observation can the

loss be determined separately at each end of a path. The purpose of this note is to clear up the prevailing misunderstanding of loss and gain concepts. --W. N.

Hay, D.R.and Turner, H. E. (both, U. of Western Ontario), Investigation of re- fractometer measurements in the atmosphere at high relative humidities and temperatures . London, Ontario. Univ. of Western Ontario. Dept. of Physics, Contract

AF 19(628)-444, Final Report, July 1963. 146 p. Numerous figs. , tables, 140

refs. , numerous eqs. (AFC RL-63-631) DWB—Results are presented from a laboratory study of the interaction with air humidity of the sensors of the microwave re- fractometer and the capacitor type refractometer. Included is a description of the

experimental technique, which employs an optical ellipsometer and a specially

designed environmental wind tunnel. It has been found that water vapor adsorption occurs at high relative humidities in both the microwave refractometer cavity

and the capacitor type refractometer sensor in amounts which cause apparent re- fractivity errors well in excess of one part per million. --Authors' abstract.

Heffner, R. W. , Ground wave propagation effects on microsecond pulses at 141

Mc/s. Institute of Electrical and Electronic Engineers, International Convention

Record, N. Y. , 11(8): 182-196, March 25-28, 1963. 17 figs. , 5 refs. , 9 eqs.

DBS —A test program was performed to investigate the propagation effects around

141 Mc/s using microsecond pulses of different carrier frequencies. These in- vestigations used omnidirectional antennas at the transmitter and receiver locations. Antenna height at both locations was 12 ft. The results to be discussed

are: a) propagation attenuation contour; b) pulse stretching; c) selective fading

and enhancement of pulses within the time frequency matrix frame; d) backscatter

pulse stretching, and e) polarization dependence. --Author's abstract.

Hirai, Masaichi et al. , Results of propagation tests at 600 Mc and 2120 Mc over long range beyond horizon paths . Japan. Radio Research Labs. , Tokyo, Journal,

10(50) :311-329, July 1963. 18 figs. , 5 tables, 7 refs. DWB, DLC -Measurements

were made at 600 Mc and 2120 Mc over 339 km and 802 km paths. Hourly medians

of the signal level over the 802 km path were characterized by very small variation during the diurnal, monthly and seasonal periods in contrast with the larger

variation observed at ranges of a few hundred kilometers. Small variation in the

hourly medians of the signal level at long ranges was closely correlated with

stable meteorological parameters in the stratosphere, favoring the theoretical

model of primary scattering. Prominent dependence of the hourly medians of the

signal level on the carrier frequencies was also observed. The ratio of the median basic transmission loss at 600 Mc to that at 2120 Mc was about 20 decibels on the 802 km path, and it corresponded nearly to the fourth power of the frequency

ratio. --Authors' abstract.
250

E-990 Hirai, Masaichi et al. , Transmission loss in VHF and UHF overland propagation

beyond the horizon. Japan. Radio Research Labs. , Tokyo, Journal, 10(51):357-

422, Sept. 1963. Figs. , tables, refs. , numerous eqs. DWB, DLC--Analysis of

the transmission loss in VHF and UHF overland propagation beyond the horizon

is made by the use of tropospheric forward scatter theory and of the results of

propagation experiment conducted over the 310 km path between Tokyo and Sendai

during the period of about 2 yrs at 159.49 Mc/s, 599 Mc/s and 2120 Mc/s, simultaneously. The transmission loss, which is defined by the ratio in decibels of

transmitted to received signal power, can be expressed by the combination of 5

terms: the basic transmission loss, the antenna beam deflection loss, the an- tenna to medium coupling loss, the transmitting antenna gain and the receiving

antenna gain. The first three losses are discussed experimentally and theoretically, and their new estimation formulas are established. Noteworthy is that the

frequency dependence of seasonal variation of basic transmission loss, the relation between the antenna beam deflection loss and the antenna-to-medium coupling

loss, and also the separation of the elevated layer reflection wave from the tropospheric forward scatter wave in the antenna beam swinging experiment are clarified experimentally and theoretically. --Author's abstract.

E-991 Hopfield, H.S. (Johns Hopkins Univ. Applied Physics Lab. , Silver Spring, Md. ), Effect of tropospheric refraction on the Doppler shift of a satellite signal . Journal

of Geophysical Research, Wash. , D. C. , 68(18): 5157-5168, Sept. 15, 1963. 12

figs. , 3 refs. , 13 eqs. DWB, DLC--An expression for the contribution made by

tropospheric refraction to the Doppler shift of a satellite signal is derived. It is

assumed that the troposphere is horizontally stratified and does not vary during

the time of a pass; a two parameter quadratic expression is used as an approximation to the refractivity profile. The qualitative effect of the troposphere during

any satellite pass is to steepen the slope of the Doppler shift versus time curve,

making the tracking station appear slightly closer to the orbit than it actually is. When Doppler data from several passes are used for orbit computation, the resultant effect of the troposphere in general is not zero; thus it may bias the orbit

slightly, the amount depending on the geometry of the selected passes. Conversely, if the orbit is assumed to be known, the station position as determined

by a single satellite pass may be shifted toward the orbit by 50 meters or more. Such errors are not negligible if precise geodetic work is to be done with satellites.

The residual tropospheric error in the Doppler shift can probably be reduced by an

order of magnitude by using a computed tropospheric correction of the type described here. Some Doppler data from observed satellite passes are presented in cor- roboration of the theory. --Author's abstract.

E-992 Isted, G.A. , Field strength surveys of VHF and UHF broadcast and television

service areas. Marconi Review, Chelmsford, 26(149): 93- 106, Second Quarter

1963. 6 figs. , 3 refs. DBS --Notwithstanding the high degree of accuracy at- tained by prediction techniques in determining the probable performance of VHF

and UHF television and broadcast services, practical measurements of field

strength still have most important functions to perform. This article describes

principally the techniques used for final measurement surveys; this is followed

by a discussion of pilot surveys with the aid of a balloon. The apparatus used

for mobile and fixed long term surveys is described, and some discussion is devoted to calibration, maintenance and automatic recording. The effect of fading

signals on the measurements is also discussed, and means are described to meet

the problem. The reporting procedure is an important feature of a practical sur- vey and this is dealt with in the article. --Author's abstract.
251

E-993 Japan. Science Council. Japanese National Committee for the URSI, Progress in

radio science in Japan. Ueno Park, Tokyo, Pub. by the Committee, Sept. 1963.

146 p. Figs. , tables, bibliog. at end of each ch. Affiliations of the researchers

p. 137-144. Addresses of the organizations p. 145-146. DWB--In Ch. 2, "Radio

and troposphere" (p. 21-43); tropospheric propagation, radio climatology, radar

meteorology and cloud physics, and space communication are considered. The

section treating tropospheric propagation discusses the following topics: a) line

of sight propagation, b) beyond the horizon propagation, c) radio propagation across mountains, and d) radio propagation over irregular terrains. --E. K.

E-994 Jones, D.S., High frequency refraction and diffraction in general media. Royal

Society of London, Philosophical Transactions, Ser. A, Mathematical and Physical Sciences, 255(1058) :341-387, Feb. 21, 1963. 7 figs. , 40 refs. , 143 eqs.

DLC, DWB--The working hypothesis of this paper is that the effect of an opaque

boundary on the propagation of high frequency waves in a general medium is to produce a wave reflected according to the laws of geometrical optics together

with a field which, to a first approximation, depends upon the difference between

the curvatures of a tangent ray and the boundary. In order to determine the latter

field, the model of a medium, whose properties vary linearly, above a straight

boundary is employed. A first approximation to the field with this model is found,

together with an estimate of the error. The formula for the field is then cast into a form which is invariant under a conformal mapping. Since the difference in cur- vatures of a tangent ray and the boundary is invariant, it is suggested that the

field is applicable for all media and boundaries provided certain conditions imposed in deriving the approximation are fulfilled. As a check, the predictions of

the formula are compared with independent calculations on (i) a stratified medium

above a straight boundary, (ii) a circular cylinder in a homogeneous medium, (iii) a parabolic cylinder in a homogeneous medium, (iv) a circular cylinder in a cir- cularly stratified medium. In all cases the two calculations are in agreement. In a final section the results are extended to phenomena which are aperiodic in time.

The proposed universal formula is simple to apply, requiring only the calculation

of rays in the medium. --Author's abstract.

E-995 Kashprovskii, V. E. and Kuzubov, F. A. , Neodnorodnosti rel'efa pochv i ikh

vliianie na rasprostranenie poverkhnostnvkh voln. (Irregularities of the soil relief

and their influence on the surface wave propagation.) Geomagnetizm i Aeronomiia,

Moscow, 3(3):525-536, May/June 1963. 10 figs. , table, 14 refs. , 8 eqs. Russian

summary p. 525. Transl. into English in the corresponding issue of Geomagnetism

and Aeronomy, Wash. ,D.C. DWB, DLC -This paper is concerned with the propagation of medium and long ground (surface) radio waves in particular their scatter- ing by the inhomogeneities of local relief over which the routes of the propagating

waves proceed. The results of determinations of the apparent conductivity, p- fc, obtained by measurements of the field potential of the radio stations over the actual paths and from computations taking into account the geometrical properties of

the terrain of these paths are presented. It is shown that it is possible in practice

to calculate the propagation of medium range ground waves on the basis of maps of

distribution of local conductivities, <y / , and analysis of the terrain of the paths.

A number of monograms for simplifying calculations are presented. The capacity

of the sea surface to scatter radio waves is analyzed. It is shown that in stormy

weather the field potential of coastal radio stations may fall several times at a distance of about 100 km and more in the case of a wave range of 300-600 m. This

phenomenon is explained by the fact that the apparent conductivity crk of the sea

surface diminishes by tens or even hundreds of times. (Met. Abs. 15. 1-103)

--I.L.D.
252

E-996 Lane, J. A. and Bean, B. R. (both, Nat'l. Bur. Standards, Boulder, Colo. ), Radiometeorological study. Pt. 1. Existing radiometeorological parameters. U.S. National Bureau of Standards, Journal of Research, Sec.D, 67(6): 589-595, Nov./

Dec. 1963. 5 figs. , 2 tables, 29 refs. , 3 eqs. (For Pt. 2, see E-969; Pt. 3, see E-968) DWB, DLC--A survey is made of existing radiometeorological parameters, including those derived from the vertical profile of refractive index, n, and others which involve the concept of thermal stability. Quantitative compari- son of radio and meteorological data confirm the value of Ns (the surface value

of n-1 10^) and N (the difference in value of Ns and N at one kilometer) in a wide variety of conditions. For particular areas, however, it seems desirable

to develop improved prediction techniques using a parameter which is related to the size, stability, and intensity of elevated layers in the troposphere. --Authors'

abstract.

E-997 Lee, Chi-chen and others (all, Dept. of Geophysics, Peking Univ. ), On the

scattering of radar wave by fluctuations of atmospheric refractivity. Acta Meteorologica Sinica Ch'i Hsiang Hsueh Pao. Peking, 33(1): 115-125, Feb. 1963. 6

figs. , table, 13 refs. , 42 eqs. In Chinese. Chinese summary p. 115; English

summary p. 125. DLC --Scattering of radar wave by fluctuations of atmospheric

refractivity is studied in this paper. The main results are as follows: 1. In case

of intensive atmospheric refractivity fluctuations, the power of back scattered ra- diation due to the refractivity fluctuations may exceed the minimum detectable

power of radar, and is of the same order of magnitude as the meteorological

"angel" wave. It is suggested that the scattering by refractivity fluctuations

may be an important mechanism in the formation of meteorological " angel " wave.

2. An equation is derived to express the wave magnitude as a function of the distance propagated in the medium with refractivity fluctuations. It is found that the

scattering effect does not affect the wave magnitude significantly in general, but

it may cause the wave width to spread when the scale length of refractivity as

well as the wave width of radar are quite small. --Authors' abstract.

E-998 Lizuka, Keigo, Experimental investigation on the behavior of the dipole antenna

near the interface between the conducting medium and free space. Harvard Univ.

Div. of Engineering and Applied Physics, Contract AF 19(604) -7262, Scientific

Report No. 4, April 15, 1963. 20 p. 14 figs. , 14 refs. (AFC RL -63-455)--A study

was made of the driving point admittance and the amplitude and phase distribution

of the current for a dipole antenna near and parallel to the interface between the

conducting medium and free space. The loss tangent of the medium, the depth

and the length of the antenna were taken as parameters. --Author's abstract.

E-999 Maenhout, A. G. , La distribution de deux parametres radiometeorologiques a Uccle (1957-1962) . (Distribution of two radiometeorological parameters at Uccle

(1957-1962).) CieletTerre, Brussels, 79(9/10): 303 -310, Sept. /Oct. 1963.

8 figs. , 5 tables, 7 refs. DWB, DLC--The author describes the statistical distribution of two radiometeorological parameters: the atmospheric refractive index

and the average gradient of this index between the ground surface and the 850 mb

level. Both values were computed twice a day at the aerological station of the

Royal Meteorological Institute (Uccle) from April 1, 1957 to March 31, 1962.

The cumulative distribution of the index and its gradient computed from the meteorological observations at OOh and 12h UT for a 5 yr period (April 1957 - March

1962) are represented in 8 graphs showing the time percentage during which the

value in ordinates is not exceeded. Some characteristic data of these distributions are represented in four tables. Another table gives the scattering of the

values of refractive index at the surface and of its gradient around their median
253

value. It is shown that this scattering is more important at 12 h than at 00 h and

in both cases it is higher in summer than in winter. --A.V.

E-1000 Martin, F.L. and Wright, F. E. (both, U.S. Naval Postgraduate School, Monterey,

Calif.), Radar ray refraction associated with horizontal variations in the refractivity. Journal of Geophysical Research, Wash. , D.C. , 68(7) -.1861-1869, April 1,

1963. 4 figs. , 2 tables, 7 refs. , 46 eqs. DWB, DLC--The relative bending ef- fects on a radio ray of the horizontal and vertical gradient of refractivity are in- vestigated. With the use of ray curvature formulas developed by WONG, convenient differential equations governing the 3 dimensional ray path are derived. It is also shown that the ratio of "horizontal to vertical' bending effects is maximum

when the ray is propagated in the vertical plane containing the horizontal gradient

of refractivity. In a two dimensional example, computations of path height as a function of horizontal distance are obtained by numerical integration. For this

purpose, a regional space-time averaged exponential model drawn from climatological studies of BEAN and THAYER has been used. Even though this smoothed model and an extreme version of it derived synthetically by increasing the horizontal

gradient everywhere by a factor of 10 have comparatively strong horizontal gradients,

the 'horizontal bending' effect is virtually negligible. It is not implied, however,

that this conclusion is necessarily applicable to an atmosphere exhibiting small

scale fluctuations in the refractivity pattern. The ray paths corresponding to the

nonhomogeneous model are significantly different from those in a horizontally uniform atmosphere. The problem of replacing a nonhomogeneous model by an equivalent horizontally uniform one is also investigated. The choice of the best uniform

atmosphere depends upon minimizing the rms height error over a designated horizontal path length, and this in turn requires the specification of several ray propagation parameters in addition to the distribution of refractivity. --Authors' abstract.

E-1001 Matsuo , Masaru, Backscatterinq measurements by an FM radar method. IEEE,

Transactions on Antennas and Propagation, ll(4):485-489, July 1963. 11 figs. , 11 refs. , 4 eqs. DLC--The principles and method for measuring the backscattering cross section of an arbitrary target demonstrates that a nonreflecting behind

the target is not requisite. --W. N.

E-1002 Meyer, Hans Klaus (German Weather Service, Central Office, Offenbach (Main) , The troposphere. (In: NATO Advanced Study Institute, Corfu, Meteorological and

astronomical influences on radio wave propagation. Ed. by Bj5rn Landmark. N. Y.,

Macmillan, 1963. p. 83-119. 16 figs. , 3 tables, 23 refs. , eqs.) DLC, DWB

(621.384 N864me)--A detailed description of the troposphere is given. The motions

and irregularities of the inversion layers, and the different aspects of turbulence

are discussed. Finally, the meteorological influences on radio wave propagation

are considered. --Author's abstract.

E-1003 Morris, D. (Nat'l. Res. Council, Ottawa), Surface wave propagation over plane

layered dielectrics. Canadian Journal of Physics, Ottawa, 41(2):405-413, Feb.

1963. 4 figs. , 11 refs. , eqs. DWB, DLC--A two layer dielectric system, consisting of a thin polystyrene sheet on top of water, is examined as a possible

guiding structure for surface waves. Experimental investigations, at a frequency

of 9. 35 Gc/sec, of the phase velocity of the waves close to the surface of the

upper layer, and the power variation with height above it, are described. A slow

wave was found to propagate near the surface and its phase velocity was found to agree with that predicted theoretically for a TM surface wave. Qualitative agreement between the experimental and theoretical power variation with height con- firmed the existence of a surface wave contribution to the total field above such a layered dielectric system. --Author's abstract.
254

E-1004 Morrow, W. E. , Jr. et al. (all, Lincoln Lab. , M. I. T. ), Influence of terrain shielding on radio wave propagation at 8000 Mc. Institute of Electrical and Electronics

Engineers, N. Y. , Proceedings, 51(6):955-956, June 1963. 2 tables, foot-ref.

DLC --Terrain shielding measurements at 8350 Mc were conducted at two locations

(1. 05 mi and 10. 8 mi distance) June 20-22, 1962 by the M. I. T. , Lincoln Lab.

Loss in excess of free space for the two sites were 102 db and 116 db respectively

and compared with 400 Mc data corrected to 8000 Mc the loss would be 96 db and

123 db. It is concluded that terrain shielding which effectively protects receivers

from neighboring high power transmitters will suffer during precipitation. --W. N.

E-1005 Muchmore, R.B. and Wheelon, A. D. , Frequency correlation of line-of-sight signal

scintillations. IEEE, Transactions on Antennas and Propagation, 11(1):46-51, Jan. 1963. 4 figs. , 12 refs. , 44 eqs. DLC --The problem is calculated theoretically,

using the spectrum method and an arbitrary model of the turbulent irregularities.

Estimate the scintillation coherence between adjacent frequencies in the RF spectrum. Correlation vs. separation frequency results are compared with experimental

results. --W. N.

E-1006 Nefedov, E. I. , Nestatsionarnye iavleniia pri beregovoV refraktsii radiovoln. (Nonstationary phenomena associated with coastal refraction of radio waves.) Radiotekhnika i Elektronika, Moscow, 8(10): 1659-1664, Oct. 1963. 2 figs. , 12 refs. , 22 eqs. Transl. into English in the corresponding issue of Radio Engineering and

Electronic Physics, N. Y. DLC--With the help of an inverse Fourier transform

applicable to exact solution of the stationary problem of radio wave diffraction at a shoreline, a solution of the nonstationary problem is obtained, which is suitable

for a broad class of pulsed signals. --Transl. of author's abstract.

E-1007 Parkinson, C.E. , Long range interference in band HI. Marconi Review, Chelmsford, 26(14): 107-116, Second Quarter 1963. 9 figs. , 3 refs. DBS --The article

gives an analysis of field strength measurements recorded in Hereford, of Mendlesham and Chill ert on Down, I.T.A. transmissions, as a means of assessing the

probable levels of co-channel interference which would be experienced by an

ancillary television station broadcasting in channel 11. The results are compared

with those from similar surveys. The correlation between the incidence of high

signal levels and anticyclonic weather conditions is demonstrated. --Author's abstract.

E-1008 Parry, Charles A. (ITT Communication Systems, Inc., Paramus, N.J. ), The aperture to medium coupling loss in tropospheric scatter systems . Institute of Electrical and Electronics Engineers, N. Y. , Proceedings, 51(6): 933-934, June 1963.

2 figs. , 9 foot-refs. , 2 eqs. DLC --Brief discussion of a new theoretical curve / plotted for comparison with the curves for the relations between loss Lc and (&/$)

of some other workers. The new curve apparently will be useful in future scatter

system design. --W. N.

E-1009 Parry, C.A. , On the prediction of the inherent bandwidth capability of the tropospheric scatter link. IEEE International Convention Record, 8:215-232, March

1963. 11 figs. , Stables, 30 refs. , 22 eqs. DLC -The tropospheric scatter mode

of propagation exhibits a multipath characteristic that limits the usable bandwidth.

In this paper, the background on this subject is briefly reviewed, and equations

are derived which may be used for estimating bandwidth in terms of intermodulation

noise level. Predicted bandwidth vs. performance curves are also given. The need

for further experimental data on this problem is strongly emphasized. --E. K.
255

E-1010 Patrick, W. S. and Wiggins, M.J. , Experimental studies of the correlation bandwidth of the tropospheric scatter medium at five giqacvcles . IEEE Transactions on Aerospace and Navigational Electronics, N. Y. , 10(2):133-137, June 1963. 12

figs. , 3 refs. , 2 eqs. DLC--An experimental program has been conducted to collect information concerning the correlation bandwidth of the tropospheric scatter

medium in the 5 Gc region. By transmitting bursts on 5 different frequencies, data were obtained on separations of 1, 5, 3. 0, 4. 5 and 6. Mc for a 100 mi path. An

IBM 7090 computer was programmed to calculate the cross correlation coefficients

between the pair of frequencies. The experimental results are in agreement with

theory, and indicate that frequencies as closely spaced as 1. 5 Mc can have cor- relation coefficients of the order of 0.4. --Authors' abstract.

E-1011 Prescott, Howard (Radio Engrg. Labs. , Inc. .Bethesda, Md.), Intermodulation distortion on tropospheric scatter systems . Institute of Electrical and Electronics

Engineers, N. Y. , Proceedings, 51(9):1244, Sept. 1963. 2 figs. , 4 foot-refs. DLC

--Pending the publication of a paper prepared on a method by which the time distribution of S/I (i. e. , signal-to-intermodulation ratio) can be determined for specific

paths, this note contains universal curves based on "smooth Earth" profiles and a surface refraciivity of Ns = 301. --W. N.

E-1012 Rainey, R. J. , Jr. and Thorn, D.C., A refraction correction technique which include

nonsymmetric index of refraction. IEEE, Transactions on Antennas and Propagation,

ll(4):446-450, July 1963. 3 figs. , 6 refs. , 13 eqs. -At White Sands Missile

Range, elevation angle errors ^> 20 the radar capabilities occur at 1° launch angle

and 50 mi range. A method to compute the atmospheric refraction directly from the

basic equation of a ray path in a variable velocity medium is described here.

»W. N.

E-1013 Rider, G.C., Weather and radar. Marconi Review, Chelmsford, 26(149): 144-162,

Second Quarter 1963. 13 figs. , 9 refs. , 5 eqs. DBS--The article reviews the way

in which meteorology and radar engineering impinge on one another. The radar

equation is briefly derived for extended targets and the optimization of its parameters is then illustrated in various circumstances according to whether precipitation is a wanted or an unwanted target. The use of radar is discussed for storm

warning, rainfall measurement, wind finding, etc. , and techniques for eliminating

weather echoes are outlined. Anomalous propagation is also mentioned. --Author's

abstract.

E-1014 Ring, Rose M. , Theoretical study of tropospheric radiowave propagation. Boston

College, Contract AF (628) -2772, Scientific Report No. 1, May 1963. 82 p. 5

figs. , 11 refs. , numerous eqs. (AFCRL-63-713) --Similar methods to those of

V.A.FOCK are used to study the following radio wave propagation problems: field

calculation, a homogeneous and an inhomogeneous atmosphere, and superrefraction. (Met. Abs. 15. 5-18)»W. N.

E-1015 Ryzhov, Iu. A. , O vliianii diaqramm napravlennosti antenn na intensivnost' prinimaevoCTQ izlucheniia pri rasseianii radiovoln na neodnorodnostiakh troposfery.

(Influence of directional patterns of antennas on received signal intensity of radio

waves scattered by tropospheric irregularities.) U.S.S. R. Ministerstvo Vysshego

i srednego Spetsial'nogo Obrazovaniia, Izvestiia Vyshikh Uchebnykh Zavedenii,

Radiofizika, 6(5):952-957, 1963. Fig., 11 refs. , 21 eqs. English summary p. 957.

DLC --The problem of the influence of receiving and transmitting antennas on parameters of received scatter signals is considered. A general formula is obtained
256

which expresses signal intensity in the form of an integral from the produce of an- tenna patterns and angular energy spectrum of the scattered field. In the particular case of narrow antenna patterns, it is shown that the functional dependence of

scattering on the parameters considered is the same as in the case of radio wave

scattering within the given volume with irregularities. --Author's abstract.

E-1016 Smith-Rose, R.L. (Vice-President, Institution of Electrical Engineers, President,

I.S.R.U. , Brussels), Radio and international geophysical research. Nature,

London, 199(4888): 11-15, July 6, 1963. DWB, DLC-This paper is the substance

of an address delivered at the U.S. National Telemetering Conference, Albequerque,

on May 21, In it the author reviews the various methods by which radio, especially

the practice of telemetry, is used in studies of atmospheric properties. The atmosphere is divided into 3 regions, the troposphere, the ionosphere and the region

above the ionosphere. Radio studies of the troposphere which are discussed are radiosonde techniques, the study of cloud and precipitation centers using radar,

atmospherics, lightning studies, 'angels', and the development of microwave re- fractometers. --R. B.

E-1017 Sweezy, W. B. and Bean, B. R. , Correction of atmospheric refraction errors in radio

height finding . U.S. National Bureau of Standards, Journal of Research, Sec. D,

67(2):139-151, March/April 1963. 9 figs. , 9 tables, 9 refs. , 31 eqs. DWB.DLC--

Atmospheric refraction errors in height finding radar are studied by means of detailed refraction calculations for a wide range of meteorological conditions. For

targets up to 70, 000 ft above ground and 150 mi ground distance from the radar site,

the mean height error was found to be as much as 5000 ft with a standard deviation

of 1200 ft. A correction for the surface value of the refractive index at the radar

site would eliminate the mean height error and reduce the maximum standard deviation to less than 900 ft. An additional correction for the initial gradient of the re- fractive index and the value of the refractive index at one kilometer above the sur- face would reduce the maximum standard deviation to less than 400 ft. Methods

of correcting height errors based on available meteorological data are presented

and shown to be operationally practical. --Authors' abstract.

E-1018 Tratas, Iu. G. , Osobennosti optimal 'nogo priema impul'snogo signala pri dal'nem

troposfernom rasprostranenii radiovoln. (Features of optimum reception of a pulsed

signal in long distance tropospheric propagation of radio waves. ) Radiotekhnika i Elektronika, Moscow, 8(4):546-551, April 1963. 3 figs. , 4 refs. , 19 eqs. Transl.

into English in Radio Engineering and Electronic Physics, N. Y. , No. 4:590-594,

1963. DLC--The detection of a pulse signal beyond the horizon is discussed. The

design of an optimum receiver is determined. The increase in the signal duration

at the receiver output as compared with the case where the transmitter and receiver

are in the line of sight is discussed. --Transl. of author's abstract.

E-1019 Tsydypov, Ch. Ts. , Vliianie rel'efa na kogerentnoe otrazhenie ukv v neodnorodnoi troposfere . (Influence of local topography on coherence of ultrashort wave

reflection in an inhomogeneous troposphere. ) Radiotekhnika i Elektronika, Moscow, 8(5):868-870, May 1963. Fig., table, 4 refs. , 8 eqs. Transl. into English

in Radio Engineering and Electronic Physics, N. Y. , No. 5:875-877, 1963. DLC--

In the coherent theory of upper tropospheric propagation of ultrashort waves the

earth is taken as an ideally smooth sphere which is not the case with actual paths.

As a result of this discrepancy the altitude of the first reflecting layer depends on

the choice of location of the terminal points of the link. In this note an attempt

is made to calculate the characteristics of topography and to obtain a formula for

coherent reflections, suitable for paths of arbitrary profile. --G.T.
257

Turner, H. E. and Hay, D. R. (both, Dept. of Physics, Univ. of Western Ontario,

Canada), Fine structure of temperature and refractivity in the lower troposphere . Canadian Journal of Physics, Ottawa, 41(10): 1732-1737, Oct. 1963. 3 figs. , 13

refs. , eq. DWB, DLC--Two improved devices were used for measuring the fine

structure of the air, in particular, the inhomogeneities in the refractive index of

the air, responsible for reflection or scattering of radar microwaves. The contrasts in air refractivity are associated with temperature fluctuations or changes

in partial pressure of water vapor. The instruments, a capacitor type refractometer and a temperature sonde which uses a resistance wire probe, both designed

for balloon borne sounding, were tested in the field with satisfactory results.

The direct measurements confirmed the existence of atmospheric irregularities,

although physically smaller than measured previously. --S. N.

Vickers, G. A. , Radio wave propagation and the planning of VHF and UHF sound

and television services. Marconi Review, Chelmsford, 26(149): 55-92, Second

Quarter 1963. 6 figs. , 8 refs. DBS --The article begins by stressing the importance of detailed planning of VHF and UHF sound and television services if the

desired service area is to be achieved within the limited number of available fre- quency channels and without causing undue co-channel interference. After a sum- mary of the chief features of radio wave propagation in these bands, the field

strength requirements for satisfactory reception are reviewed and the relative per- formance in the 3 television bands is contrasted. Since the planning requires a knowledge of the relationship between radiated power and field strength at each

receiving locality, the various available methods of establishing this relationship

are discussed, with special reference to the theoretical or "paper" method used

extensively by the Marconi Co. A description is given of the estimation of co- channel interference levels and the preparation of predicted coverage maps, and

the article ends with a review of some of the many practical aspects of the plan - ning, including the selection of transmitting sites. --Author's abstract.

Waibel, E. (Inst, fur Stratospharen-Physik, Hannover, Germany), Method to eliminate noise during the transmission of radio pulses . Review of Scientific

Instruments, N. Y. , 34(l):31-33, Jan. 1963. 4 figs. , 5 ft. refs. DWB, DLC--

The wide frequency emission band of noise signals which interfere with signals

of radio transmitters is used for eliminating these noise signals. They are re- ceived separately beside the telemetering frequency and are quenched by a suitable anticoincidence circuit. --Author's abstract.

Wait, J. R. , Oblique propagation of ground waves across a coastline. Pt. 1. U.S. National Bureau of Standards, Journal of Research, Sec. D, 67(6):617-624,

Nov. /Dec. 1963. Pt. 2 . by J. R. Wait and C. M. Jackson, Ibid. , 67(6) -.625-630,

Nov. /Dec. 1963. --In Pt. 1, the amplitude and phase of the ground wave are calculated for oblique propagation across a flat lying coastline. This land and

sea are assumed to be smooth and homogeneous. Attention is focused on the

effects which take place near the coastline. It is shown that the reflected wave

depends critically on the angle of incidence, Gff , while the transmitted wave

has only a weak dependence on Ba . In Pt. 2, the amplitude and phase are calculated for oblique propagation across a coastline with a sloping beach. In this

case, the land and sea are taken to be plane surfaces and the beach slope is

constant. It is shown that the reflected wave may be quite significant and it has a fundamentally different character from the reflected wave in the case of a flat lying coastline. --Author's abstract.
258

E-1024 Wait, James R. (NBS, Boulder, Colo.), Review of mode theory of radio propagation in terrestrial waveguides. Reviews of Geophysics, Wash. , D.C. , 1(4) ^SISOS, Nov. 1963. Bibliog. p. 500-505, 98 eqs. DWB--This paper is an expository

review of the theory of guided waves that occur in the Earth's atmosphere. We in- troduce the subject by treating the problem of radio propagation around the surface

of an airless spherical Earth. This leads readily to the classical solutions of

VAN DER POL and BREMMER and the more recent work of FOCK in the USSR. The

influence of a troposphere with a smooth profile of refractive index is then considered. This analysis, which follows the recent work of ARMAND, confirms

that a monotonically varying or smooth profile will not change the basic structure

of the diffraction field. The modifications resulting from the presence of a tropospheric duct are developed by using a parabolic profile of refractive index in the manner suggested by FOCK, WEINSTEIN, and BELKINA. It is shown that the dominant modes in this system have low attenuation. The second and major part of

the paper is devoted to the theory of the mode propagation of VLF radiowaves.

Here the effective waveguide is the space formed by the Earth's surface and the

lower edge of the ionosphere. The mode solution is developed as a natural generalization of the classical airless Earth theory. It is shown, for frequencies

less than about 10 kc/s, that the field may be described in terms of flat Earth

modes analogous to those in a straight rectangular microwave guide. At higher

frequencies, however, the Earth curvature plays a major role and the character

and excitation of the modes are changed drastically. Complications resulting from

the anisotropy of the ionosphere are also considered. A critical discussion of the

recent work on the subject is given. --Author's abstract.

E-1025 Wait, J.R.and Walters, L.C., Curves for ground wave propagation over mixed

land and sea paths. IEEE, Transactions on Antennas and Propagation, ll(l):38-45,

Jan. 1963. 9 figs. , 20 refs. , 14 eqs. DLC--Specific numerical results are presented for ground wave propagation over paths which are part sea and part land.

The problem is idealized to the extent that earth is a smooth spherical surface. The

method is based on a previous formulation in terms of mutual impedance between

two vertical electric dipoles on an inhomogeneous spherical earth. Amplitude and

phase of the ground wave are given for various combinations of the following parameters: frequency 1000, 100, and 20 kc; land conductivities 100 and 10 mmhos/m;

and a sea conductivity of 4 mhos/m. Most of the curves exhibit the well known

recovery effect which occurs beyond the coast line for propagation from land toward

the sea. --Authors' abstract.

E-1026 Waterman, A.T. , Jr. and Strohbehn, J. W. (both, Stanford Univ. ), Reflection of

radio waves from undulating tropospheric layers. U.S. National Bureau of Standards, Journal of Research, Sec. D, 67(6): 609-616, Nov. /Dec. 1963. 9 figs. , 14

refs. , 8 eqs. DWB, DLC--This report examines the nature of coherent reflections

of radio waves at near grazing incidence, from a horizontal atmospheric layer on which is superimposed a slight wave motion. The existence of reflections of this

type is merely postulated, and the development then proceeds to examine the con- sequences of such a postulate with reference to measurements obtainable in trans- horizon propagation experiments. The properties of angle of arrival, signal level,

fading rate, and Doppler shift are examined, together with their rates of change

with time. --Authors' abstract.

E-1027 Watt, A.D. ; Mathews, F.S.and Maxwell, E.L. (all, DECO Electronics, Inc. , Boulder Div. , Boulder, C olo. ) , Some electrical characteristics of the Earth's crust . Institute of Electrical and Electronics Engineers, N. Y. .Proceedings, 51(6):897-

910, June 1963. 18 figs. , table, 39 refs. , 16 eqs. DLC--Wave propagation over
259

ground, particularly at <. 10 cps is affected by the changing conductivity of sur- face materials and conditions. Measurements of ground conductivity from samples

or in situ by 1) the bridge method, 2) four electrode array and 3) the magnetotelluric method are discussed. Conductivity variations with depth below surface for frequencies between 0-10 cps are considered. Conductivities of various soils,

rocks and water as well as of snow, ice and permafrost are tabulated. Temperature and pressure affect the electric properties of the Earth's surface materials,

the conductivity of which was found to range from 5 mhos/m for sea water to between 10"° and 10-9 mhos/m for very dry rocks. --W. N.

E-1028 Weston, V.H. , Theory of absorbers in scattering . IRE Transactions on Antennas

and Propagation, 11(5): 578-584, Sept. 1963. Fig., table, 10 refs. , 21 eqs. DLC--

Two new theorems are introduced. Considers the effect of absorbers on scattering

from complex shapes, diffracted field taken into account. High frequency scatter- ing from any smooth convex body is examined. Uses the conditions given in the

theorems to determine their effect on the creeping waves, greater attenuation of

which would be less from a perfectly conductive surface. Shows how highly re- fractive absorbers reduce back scattered cross section for smooth convex bodies

in the resonance region. --From author's abstract.

E-1029 Whale, H. A. (Seagrove Radio Research Station, Univ. of Aukland, New Zealand),

Focusing effects in spherical Earth radio propagation. Nature, London, 197(4870):

886-887, March 2, 1963. 2 refs. DWB, DLC-The flat Earth scattering theory for the propagation of short radio waves over long distances has been extended to cover propagation around a spherical Earth. Using a coordinate system, in which

the transmitter is located at the pole and the transmitter is located by means of a co-latitude and a longitude measured from the direction of maximum strength of the

transmitted beam, formulas are given for the distribution of received power, the

standard deviation of the spread of the incoming fan of waves and the extent of

the antipodal area. Along a line at 260° angular distance from the transmitter the

deviation of the main incoming direction from the great circle is zero, irrespective

of the beamwidth, direction or ionospheric scattering coefficient of the transmitter.

It is proposed to call this line the reciprocal line to the transmitter. (Met. Abs.

14. 10-167) --R.B.

E-1030 Wood, H. B. (Standard Telecommunication Labs. , Ltd. ), Performance of v. f . f. m. teleprinter circuits operating over a tropospheric scatter link. Institution of Electrical Engineers, London, Proceedings, 110(11): 1933-1940, Nov. 1963. 10 figs. , 3 refs. , 13 eqs. DLC--The paper describes an investigation undertaken to derive

data on which to base estimates of the telegraph performance to be expected over tropospheric scatter radio links. H.B.LAW has shown how the telegraph error rate depends on the signal/noise ratio at the input to the telegraph equipment for the case of a steady signal, and also for the case of one subject to Rayleigh fading. As the signal received over a tropospheric scatter link has a short term

amplitude distribution following the Rayleigh law, it might be expected that LAW's

results could be applied directly. The problem is complicated, however, by the

fact that most operational scatter links employ frequency modulation of the radio

carrier, with the result that the receiver exhibits threshold effects. When the

fading signal falls below the receiver threshold, which it may frequently do, the

output signal/noise ratio is no longer linearly dependent on the input carrier/noise

ratio. It is shown, however, that, if the output/input characteristic of the radio

receiver is known, the telegraph error rate can still be calculated in terms of the

mean carrier/noise ratio. An empirical law for the output/input characteristic of an f . m. radio receiver is proposed, and, using this law, the telegraph performance

of circuits carried by tropospheric scatter links is then calculated for the cases of

non-diversity and dual and quadruple selector type diversity receiving systems.
260

It was considered desirable to make experimental checks, and an analogue method

was employed in which the effects of the radio path were recorded and used to operate a fading machine, so as to reproduce, in the laboratory, the conditions

which had existed over an actual radio path. A comparison is made of predicted

values of telegraph error rate with experimental results obtained using the fading

machine. --Author's abstract.

E-1031 Zhevakin, S. A. and Naumov, A. P., Q koeffitsiente pogloshcheniia elektromag - nitnykh voln vodianymi parami v diapazone 10 1^+ 2 sm. (Absorption coefficient

of electromagnetic waves by water vapor in the 10 U- t 2 cm range.) U.S.S.R.

Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia Vysshikh Uchebnykh Zavedenrf, Radiofizika, 6(4):674-694, 1963. 17 figs. , 2 tables,

54 refs. , 19 eqs. English summary p. 694. DLC —Calculations are made of the absorption of radiation in the 10/4+2 cm range by atmospheric water vapor. The

shape of lines is obtained from a solution of the kinetic equation and half widths

of lines are calculated by using Anderson's theory. Matrix elements of the direction cosines for the rigid asymmetrical top are used, however, centrifugal perturbation is taken into account in counting the molecular terms of H2O. The results

are in good agreement with experiment. --Authors' abstract.

1964

E-1032 Bell, M.B. ; Hay, D. R.and Johnston, R.W. (all, Univ. of Western Ontario,

London, Ont.), Observations upon clear air stratification in the lower troposphere.

Canadian Journal of Physics, Ottawa, 42(2): 273-286, Feb. 1964. 5 figs. , 2 tables,

27 refs. , 6 eqs. DWB, DLC--A study of the fine structure of air refractivity in the

lower troposphere has been continued through the spring and summer of 1962 by the

observation of weak radio reflections from clear air (radar angels), with a vertically directed radar of special design operating at 6770 Mc/s. These observations

have been limited to the layer of frictional influence, within 1500 meters of the

surface. The interpretation suggests that the reflecting centers are broad strata whose refractivity contrasts weakly with that of their environment, whose vertical

depths are no more than a few centimeters, and which are either flat over horizontal distances of at least several meters or concave downwards with radii of curvature somewhat less than their height above ground. The incidence of transitory

reflections generally follows a regular distribution in the vertical, with a maximum

at 300 m; the form of this distribution is modified by the intrusion of weather fronts,

thermals, and other clear weather structures. The transitory reflecting stratus is

cut off from its generating source early in its life history, to be dispersed into its

environment by molecular or eddy diffusion. The total incidence of transitory

angels fluctuates quasi-periodically in time, with a period of about 10 min; it is

suggested that this periodicity is due to the influence of internal gravity waves in

the atmosphere. In contrast, persistent reflections are associated with a more

stable environment; the maximum incidence is at the lowest heights observed,

with a gradual decrease toward higher levels. Their relationship to clear weather

structure is less certain than for the transitory reflections. The persistent reflecting stratus must be replenished continuously by the generating source during its

lifetime to offset diffusion into the environment. --Authors' abstract.

E-1033 Braam, G. P. A. (Royal Netherlands Meteor. Inst. , De Bilt), Propagation of radio

waves with frequency 99. 9 Mhz as a function of the vertical structure of the atmosphere derived from daily radiosonde observations . U.S. National Bureau of Standards, Journal of Research, Sec. D, 68(2): 257-260, Feb. 1964. Fig., 5 tables, 14

refs. DWB, DLC--A special parameter was derived from radiosonde observations

to indicate the atmospheric structure. The relation between this parameter and the
261

propagation of UHF radio waves beyond the horizon was investigated statistically.

It was found that this relation was strong at midnight, but much weaker, though

not absent, at noon. As an analogous difference exists between summer and winter data, it is suggested that for abnormal propagation apart from special layers

with a large gradient of the refractive index, also, a stable atmosphere in the lower

levels is required. --Author's abstract.

E-1034 Gjessing, Dag T. , An experimental study of the variation of the tropospheric scat- tering cross section and air velocity with position in space . IEEE Transactions on Antennas and Propagation, N. Y. , 12(l):65-73, Jan. 1964. 17 figs. , 10 refs. , 8

eqs. DLC--An experimental study of the spatial homogeneity of the tropospheric

permittivity and air velocity fields is presented. Knowledge regarding the homogeneity is imperative in order to measure the 4 dimensional spectrum of the permittivity fluctuations to be discussed in a later report. It is found that in most cases

the scattering ability of the troposphere is enhanced with height. The variation of

scattered power with position of the scattering volume along a horizontal direction

varies very little. Similarly, it is shown that the wind velocity varies very little with height in the height region under consideration, while the velocity varies

somewhat in a horizontal direction. Velocity and scattered power do not seem to correlate. --Author's abstract.

E-1035 Gjessing, Dag T. and Irgens, F. , On the scattering of electromagnetic waves by

a moving tropospheric layer having sinusoidal boundaries . IEEE Transactions on Antennas and Propagation, N. Y. , 12(l):51-64, Jan. 1964. 12 figs. , 15 refs. , 24 eqs. DLC--The transhorizon signal is assumed to be adequately described by

a simple Waterman scatter model and to be ascribable to a partial reflection from

a rippled atmospheric layer. Here it is assumed that the boundary of this layer is

space sinusoidal in a plane normal to the line determined by the transmitter and

receiver points. The thickness of the layer is approximately uniform and the per- mittivity is assumed to vary in a Gaussian manner. Theoretical and experimental

descriptions of the vertical transverse permittivity spectrum are obtained and compared. A corresponding comparison is made between the theoretical and Waterman

experimental received power vs azimuth angle patterns. In both cases, there is a qualitative agreement provided the ratio of ripple amplitude wavelength is large. In addition an estimate of the transhorizon signal power spectrum is compared with

experimental observations. Experimentally, the power spectrum is found to broad- en with increasing scattering angle and beamwidth, while the present scatter model

yields a power spectrum whose width is an inverse function of scattering angle

and beamwidth. --Authors' abstract.

E-1036 Kane, Julius (U. of R. I. , Kingston) and Karp, Samuel N. (Div. of Electromagnetic

Research, N. Y.Univ. ), Simplified theory of diffraction at an interface separating

two dielectrics . U. S. National Bureau of Standards, Journal of Research, Sec. D,

68(3):303-310, March 1964. Figs., 10 refs. , 18 eqs. DWB, DLC -Many electromagnetic problems involving more than one dielectric medium are not susceptible

to an exact solution, when the appropriate boundary conditions are considered.

The purpose of the present paper is to formulate a new boundary condition, which

is capable of leading to mathematically tractable problems, with limited sacrifices in accuracy. --Authors' abstract.

E-1037 Misme, Pierre, Le feuilletage atmospherique. (Atmospheric foliation.) Annales

des Telecommunications, Paris, 19(1-2) -.49-59, Jan. /Feb. 1964. 6 figs. , 2 tables,

17 refs. , 22 eqs. DLC -It is shown that irregularities of the horizontal fields of

temperature and humidity at a given level manifest themselves as pressure
262

irregularities at another level. Horizontal air movements in the atmospheric layer

between these two levels are studied. It is found that above a certain altitude the

horizontal oscillatory movements destroy the source of the pressure irregularity and

this leads to "foliation" The atmosphere is considered as a thermal machine containing warm and cold sources, the difference between the two being maintained by

the radiative balance. This makes it possible to calculate the amount of thermal

energy being transformed into movement. Using Obukhov's hypothesis, the smallest size of turbulent elements is calculated, which makes it possible to determine

the vertical distance between "foils". The study is generalized to apply to all levels of the atmosphere. Experimental examples taken from different authors are

in agreement with this theory. An appendix indicates a method for identifying

foliation in the upper stratosphere. --Transl. of author's abstract.

E-1038 Misme, P. , Radioelectricite et troposphere (Commission II. 14 Assemble e Generale de l'U. R.S. I. . Tokyo. Sept. 1963) . (Radioelectricity and troposphere,

Commission 2, 14th General Assembly of the I. U.S. R. , Tokyo, Sept. 1963.)

L'Onde Electrique, Paris, 44(444): 234-237, March 1964. 2 figs. DBS-Contains

brief summaries of reports presented to the Commission by some 20 authors on

progress achieved in the study of atmospheric models, radio climatology, radar

meteorology, tropospheric influences on space communication, influence of ter- rain irregularities, and propagation of millimeter waves. --G. T.

E-1039 Wait, James R. (Central Radio Propagation Lab. , Nafl. Bur. of Standards, Boulder,

Colo.), Oblique propagation of ground waves across a coastline. Pt. 3. U.S. National Bureau of Standards, Journal of Research, Sec. D, 68(3): 291 -295, March

1964. 8 figs. , 5 refs. , 16 eqs. DWB, DLC--This paper, which is a continuation

of two earlier papers of the same title, (See E-1023), contains numerical results

for the field anomaly near a coastline when the surface impedance changes in a

linear manner between land and sea. The earlier results for an abrupt boundary

are recovered as the width of the transition region is reduced to zero. In general,

it is found that the characteristics of the transition region will not produce significant modifications of the transmitted field. However, the magnitude of the re- flected field is greatly reduced as the width of the transition zone is increased

beyond about one-quarter wavelength. --Author's abstract.

E-1040 Wait, J. R. (Central Radio Propagation Lab. , Nat'l. Bur. of Stds. .Boulder, Colo.),

Coherence theories of tropospheric radio propagation . IEEE Transactions on Antennas and Propagation, N. Y. , 12(5):649-651, Sept. 1964. 11 refs. , 6 eqs.

DLC --Using a model atmosphere refractive index, which is maximum at ground

level, decreasing monotonically to the free space value at greater height, an

attempt is made to appraise the existing and fundamentally disagreeable two approaches to the problem. --W. N.

E-1041 Wait, J. R. and Jackson, CM. (both, Central Radio Propagation Lab. , Nat'l. Bur.

of Stds. , Boulder, Colo.), Influence of the refractive index profile in VHF reflection from a tropospheric layer. IEEE Transactions on Antennas and Propagation,

N. Y. , 12(4): 512-513, July 1964. 3 figs. , 4 refs. , 16 eqs. DLC -This theoretical

investigation shows what happens when the change of refractive index ( ) is not

abrupt but is a continuous function of height . Notwithstanding consideration to the finite horizontal extent of the tropospheric layers as in a practical situation,

the results presented provide insight into gradient-type reflection. --W. N.

E-1042 Wait, J. R. (Nat'l. Bu. of Standards, Boulder, Colo.), Note on VHF reflection from

a tropospheric layer. U.S. National Bureau of Standards, Journal of Research,

Sec. D, 68(7):847-848, July 1964. 2 figs. , 4 refs. --Some remarks concerning re- flection from tropospheric layers are made with special reference to a recent paper

by Bean, Frank, and Lane on the subject. It is indicated that the finite vertical

extent of the layer must be considered in the analysis.
263

SUPPLEMENTARY MATERIAL

Ames, L.A. ; Martin, E. J. and Rogers, T.F. (all, A. F. Camb. Res. Ctr. , Bedford, Mass.), Some characteristics of persistent VHF radiowave field

strengths far beyond the horizon . Institute of Radio Engineers, N. Y. , Proceedings, 47(5, Pt. 1): 769-777, May 1959. 13 figs. , 32 refs. DWB-The

most recent results of a continuing research program devoted to the study

of long distance VHF radiowave propagation are presented. Data obtained

from measurements made at 50 and 220 mc on the surface and in the air are given which extend our previous results and clarify some important aspects

of tropospheric and ionospheric propagation at extreme distances and

heights. (Met. Abs. 11 E-9) -Authors' abstract.

Barghausen, A.F. ; Decker, M.T. and Maloney, L.J. , Measurements of

correlation, height gain, and path antenna gain at 1046 megacycles on spaced antennas far beyond the radio horizon. Institute of Radio Engineers, N. Y. , Convention Record, Pt. 1:78-81, 1955. 5 figs. DLC

(TK 6541. 15) --Studies made and reported by the National Bureau of Standards in 1953 on the correlation of 1046 Mc radio fields on spaced antennas

at distances far beyond the radio horizon are supplemented by more recent

measurements. Measurements were made on the NBS Cheyenne Mountain

transmission path in Colorado and Kansas at a frequency of 1046 Mc, the

receiving location being at an angular distance of 27 milliradians (for

standard atmosphere), i. e. , approximately 150 mi beyond the transmitter

radio horizon. In addition to the correlation of instantaneous fields, the

correlation of hourly median fields and the diurnal variation of the re- ceived signals are shown. (Met. Abs. 8J-65)--From authors' abstract.

Barsis, A. P. ; Herbstreit, J. W. and Hornberg, K. O. , Cheyenne mountain tropospheric propagation experiments . U.S. National Bureau of Standards, Circular

No. 554, Jan. 3, 1955. 39 p. 46 figs. , 2 tables, 18 refs. , eqs. -Measurements

at five frequencies from 92 to 1046 Mc/s were conducted over 393 and 617 mi

paths and reported on. The studies include effects of rough terrain, dependence

of transmission loss on refractive index profiles, height gain functions and application of related theories, e.g. the new theory of propagation embodying

Booker-Gordon's scattering principles as extended by Staras. — W. N.

Barsis, A. P. and Capps, F. M. (Nat'l. Bur. of Standards, Boulder, Colo.),

Effect of superrefractive layers on tropospheric signal characteristics in the

Pacific coast region. Institute of Radio Engineers, IRE Wescon Convention

Record, Pt. 1:116-133, 1957. 11 figs. , table, 10 refs. DLC-Results of

tropospheric radio wave propagation measurements over two paths between

San Nicolas Island and the California coast near Pt. Mugu are correlated with

the characteristics of refractive index profiles determined at the path terminals

simultaneously with the radio measurements. The radio paths extend to the

vicinity of and slightly beyond the radio horizon. Specifically, it was found

that the existence of superrefractive layers (either ground-based or elevated)

favors the occurrence of prolonged space-wave fadeouts for the within-thehorizon path, and increases the short term fading range for the beyond-thehorizon path. It was found that the base and top elevations of a superrefractive
264

layer, and also the magnitude of the refractive index gradient within the layer

have a noticeable effect on various characteristics of the received signal for both paths. An example of this is found if the hourly median basic transmission loss for the beyond-the-horizon path is plotted as a function of the layer

heights. These results generally agree with earlier observations by Smyth and

Trolese. --Authors' abstract.

E-1047 Bean, Bradford R. and Cahoon, 3. A., The effect of atmospheric horizontal inhomoqeneity upon ray tracing. U.S. National Bureau of Standards, Journal of

Research, Sec. D, 63(3) -.287-292, Nov. /Dec. 1959. 6 figs. , 2 tables, 11 refs.,

9 eqs. DWB, DLC. Also issued as: U.S. National Bureau of Standards, NBS

Report No. 6054, April 10, 1959. 13 p. 6 figs. , 2 tables, 10 refs. , 9 eqs.

DWB (621.384 U585ef)--The tracing of radio rays is normally carried out under

the assumption that the refractive index varies only in the vertical direction.

Although this assumption appears to be quite reasonable in the average or climatic sense, it is seldom satisfied under actual conditions and is strongly

violated by horizontal air mass changes occurring near frontal and land-sea

interfaces. This latter case is investigated by tracing rays through two instances of observed marked horizontal variation of the refractive index. The

bending for these ray paths were then compared with values obtained under the

normal assumption of horizontal homogeneity. Although at one kilometer and

above these horizontal changes appear to have little effect, rays emitted at low

elevation angles are sensitive to extreme horizontal variations of the atmosphere

near the surface, such as those associated with ducting conditions. However,

since it appears that such conditions occur less than 15% of the time at most

locations, the majority of ray path calculations may be carried out under the

normal assumption of horizontal stratification of the refractive index. (Met. Abe.

12. 6-142) -Authors' abstract.

E-1048 Beckmann, Petr, Statistical distribution of the amplitude and phase of a multiply

scattered field. U. S. National Bureau of Standards, Journal of Research, Sec. D,

66(3): 231-240, May/June 1962. 19 figs. , table, 13 refs. , 52 eqs. DWB, DLC--

The probability distribution of the amplitude and phase of the sum of a large

number of random two-dimensional vectors is derived under the following general

conditions: Both the amplitudes and the phases of the component vectors are random, the distributions being arbitrary within the validity of the Central Limit

Theorem; in particular, the distributions of the individual vectors need not be

identical, the amplitude and phase of each component vector need not be independent and the distributions need not be symmetrical. The distributions formerly derived by Rayleigh, Rice, Hoyt, and Beckmann are shown to be special cases of this distribution. --H.T. D.

E-1049 Bogle, A. G. , Some aspects of microwave fading on an optical path over sea . Institution of Electrical Engineers, London, Proceedings, Pt. Ill, 99(61) :236-240,

Sept. 1952. 6 figs. , 9 refs. DLC --Long term measurements of microwave transmission over a 39 mi optical path have shown fading too deep to be easily ac- counted for by simple theory. It is concluded from experimental evidence that

both scattering from turbulence and movements of the interference pattern contribute to the fading. --
265

E-1050 Bremmer, H. , On the theory of fading properties of a fluctuating signal imposed

on a constant signal. U. S. National Bureau of Standards, Circular 599, May 25,

1959. 32 p. 9 refs. , eqs. DLC (Q C 100. U555) --This paper deals with a theoretical investigation of the fading properties of a signal composed of a fluctuating

contribution, and another steady contribution with fixed amplitude and phase. It is assumed that the central limit theorem may be applied to two proper quantities

describing the fading signal as a quasi-monochromatic function of the time. The

results are applicable to any autocorrelation function for the fluctuating contribution. The first part of the paper (sections 1 - 16) is mainly restricted to the

idealized case in which any two components of the fluctuating part of the complete signal that are in quadrature with respect to their phase do have identical

statistical properties; the fluctuating part is then termed a "random" signal.

This idealized case is fhown to constitute but an approximation if applied to the

fluctuating field due to first order scattering in a turbulent atmosphere. Therefore,

in the second part of the paper (sections 17 - 26), the theory has been extended

to fluctuating contributions (then termed "quasi-random" contributions) not

satisfying the above condition of isotropy. All results then depend on two complex correlation functions a(r) and b(r) instead of on the single function a(r)

governing the simplified theory. In contrast to a(r) the function b(r) does not

exclusively depend on the energy spectrum of the fluctuating contribution.

--From author's abstract.

E-1051 Brilliant, Martin, Fading loss in diversity systems. Institute of Radio Engineers,

Transactions on Communication Systems, 8(3):173-176, Sept. 1960. Fig. , 27 eqs.

DLC --In a communication system using optimum diversity combining the mean

signal-to-noise ratio of the combined signal is the sum of the mean signal-to-noise

ratios of the separate signals. However, the effective signal-to-noise ratio of

the combined signal is less than this. The ratio of the mean to effective signalto-noise ratios of the combined signal is called the fading loss. The effective

signal-to-noise ratio, and hence the fading loss, depends upon the measure of

effectiveness used, which in turn depends upon the form of information conveyed

by the signal. In a high quality speech system, the fading loss is shown to depend principally upon the order of diversity (the number of signals combined). In a binary communication system, the fading loss is shown to depend principally

upon the mean signal-to-noise ratio of the separate signals. The system design

considerations in these two cases are therefore different. --Author's abstract.

E-1052 Clarke, R.H. (Bell Tel. Labs. , Inc. , Holmdel, N. J. ) and Hendry, G. O. (Brobeck

& Ass. , Berkeley, Calif.), Prediction and measurement of the coherent and in- coherent power reflected from a rough surface. IEEE Transactions on Antenna and

Propagation, N. Y. , 12(3): 353-363, May 1964. 6 figs. , table, 15 refs. , 57 eqs.

DLC --Experimental measurements of the behavior of radio wave signals of 8-40

mm reflected from a rough sea surface are described. A slightly modified ver- sion of Manton's original apparatus was used. The two components of the random

signal; one in phase with the constant signal, the other in phase quadrature, are not equal in variance except for very rough surfaces. The theoretical results are shown to conform with the experimental ones. --W. N.

E-1053 Crain, C. M. and Booker, H. G. (both, Rand Corp.), Effects of nuclear bursts in

space on the propagation of high frequency radio waves between separated Earth

terminals . Journal of Geophysical Research, Wash. ,D.C. , 68(8): 2159-2166,

April 15, 1963. 3 figs. , 4 tables, ref. , 21 eqs. DWB, DLC -Discusses a possible method for detecting nuclear bursts in space. The method is based on the
266

effects that the bursts should have on the phase and amplitude of high frequency

radio transmission between separated terminals on the Earth's surface. Relations

are derived that show how these effects should vary with time after the nuclear

detonation and how they are related to bomb temperature, yield, and distance

from the Earth. The phase shift is independent of bomb temperature over a wide

range of temperatures, whereas attenuation decreases by a factor of about 10 (db)

for each 50% decrease in bomb temperature. Thus, absorption measuring techniques

become decreasingly attractive for detecting cooler bombs. It is concluded that

measurements of high frequency phase and amplitude change, in conjunction with

very low frequency phase measurements, may provide a very sensitive means for detecting nuclear bursts in space by ground based radio equipment, even for quite

cool bombs. The possibility of determining bomb temperature is also shown.

(Met. Abs. 14. 9-165) -Authors' abstract.

E-1054 Decker, Martin T. , Airborne television coverage in the presence of cochannel

interference. U.S. National Bureau of Standards, Technical Note No. 134, Jan. 1962. 16 p. Appendix with 56 figs, (no pagination), 19 refs. DLC --Predictions are made of the coverage to be expected from a network of airborne television

transmitters operating in the UHF television band. Various system performance

and interference conditions are assumed. The results are presented in a series

of graphs with probability of service as a function of receiving location and in

terms of the total effective area of a station or network of stations. System re- quirements for a coverage approaching 100% of a large area are indicated.

--Author's abstract.

E-1055 Dougherty, H.T. and Maloney, L.J. (both, Central Radio Propagation Lab. , Nat'l. Bur. of Standards, Boulder, Colo.), Application of diffractions by convex surfaces

to irregular terrain situations. U.S. National Bureau of Standards, Journal of Research, Sec. D, 68(2): 239-250, Feb. 1964. 10 figs. , 25 refs. , 18 eqs. -Previous

solutions by Rice and by Wait and Conda are combined and extended to provide more readily evaluated formulas for the diffraction of radio waves by the "rounded

obstacles" encountered in irregular terrain situations. A comparison with experimental data is also provided. --Authors' abstract.

E-1056 Freeman, J. A. and Chen, Y. Y. (NASA Goddard Space Flight Center. System

Analysis Office, Beltsville, Md. ), Compensation of tropospheric effects on Doppler tracking. IEEE Transactions on Antennas and Propagation, N. Y. , 12(4):

513-514, July 1964. Fig. , 2 tables, 4 refs. DLC --Condensed description of a method of measurements of range rate. Details to appear shortly in a NASA

Technical Note. --W. N.

E-1057 Gough, M. W. , VHF and UHF propagation within the optical range. Marconi

Review, No. 95, 12(4): 121-139, Oct. -Dec. 1949. 14 figs. , tables, refs. in

footnotes, eqs. DLC --The mechanism of VHF and UHF propagation can be ex- plained in terms of five major factors, namely: (1) atmospheric refraction; (2)

ionospheric reflections; (3) tropospheric reflections; (4) diffraction; (5) Ground

reflections. (5) is the dominant influence on propagation within the optical range,

and it is with this aspect of the problem that this article is concerned. From the

ray concept of propagation, a technique has been evolved using simple microwave field strength measurements to forecast the behavior of VHF and UHF transmissions over a specific optical path. In particular, the method predicts, without further measurement, the best height for the receiving aerial on any frequency

in the VHF or UHF band. The process is based on the assumption that ground
267

reflection is confined to a point. This assumption becomes increasingly invalid

with increasing wavelength and may lead to errors. However, these can be cor- rected to a large extent by evoking Fresnel's zone theory, which defines what

region of the path is involved in reflection. Furthermore, by examining the

ground irregularities in this region the reflecting power of the ground can be

assessed. This article develops the theory of the microwave survey technique

and describes and interprets a survey made over a test path, from which the

behavior of specific longer waves is predicted. It concludes with a description

of confirmatory experiments made over the same path which verify the predictions.

The "calibration" of optical paths by the use of microwaves eliminates the necessity for tests on operational wavelengths, and coupled with the lightness and

compactness of microwave equipment, saves experimental labor, particularly if the path is to carry transmissions on more than one wavelength. --Author's

abstract.

1058 Gudmandsen, P. and Larsen, B. F. , Statistical data for microwave propagation

measurements on two oversea paths in Denmark. Institute of Radio Engineers,

N. Y. , Transactions on Antenna and Propagation, 5(3):255-259, July 1957.

7 figs. , 4 refs. DLC --Measurements were carried out on 6.4 cm and 17 cm

wavelength on two optical paths, 54 km and 82 km long, stretching over sea

nearly East-West and starting at the same point. For the greater part of the

measurements, height spaced receivers were used. The bulk of the statistical

data comprises distributions of field strengths for every day of measurement.

Curves for single receivers and diversity combinations of two receivers have

been worked out. Distributions for every hour of a day, as well as distributions

of fadurations for a few days with special propagation conditions, were obtained.

A study of special fading phenomena with almost coinciding fades on the re- ceivers in operation has been made. The data reveal that the field strength distribution for single receivers on days with a great number of fades generally approximates the Rayleigh distribution irrespective of wavelength path, and an- tenna height within the range of height considered. The field strength distributions for diversity systems approximate the diversity Rayleigh distribution,

which is derived from two uncorrelated Rayleigh distributed signals. Deviations

from appropriate Rayleigh distribution toward more serious fading conditions seem

to be more frequent and more pronounced for diversity systems than for single re- ceivers. Distributions of fade durations are found to be log-normal. Measurements on three height spaced receivers on 17 cm wavelength indicate that the

simple two ray theory is insufficient to describe the fadings on a path over sea. --Authors' abstract.

Herbstreit, J. W. (Nat'l. Bur. of Standards, Boulder), Radio refractometrv. International Scientific Radio Union. Commission II on Radio and Troposphere,

Monograph on radiowave propagation in the troposphere: Proceedings of the

Commission, 13th General Assembly of URSI, London, 1960. Amsterdam,

Elsevier Pub. Co. , 1962. p. 187-196. Table, 44 refs. , 2 eqs. English and

French summaries p. 187. DLC (QC973. 1575), DWB (M10. 62 I61mo)«

A discussion of the refractive index measurement of the troposphere at radio

frequencies, with particular reference to measurements made by the radiosonde

technique and by radio refractometers. The application of radio refractometry

to propagation problems is also considered. (Met. Abs. 14. 9-171)--Author's

abstract.
268

E-1060 Hubbard, R. W. and Thompson, M.C.Jr. (Nat '1. Bur. of Standards, Boulder,

Colo.), Phase generator for tropospheric research. Electronics, N. Y. , 29(10):

220-223, Oct. 1956. 4 figs. , photo. , 7 refs. DLC- -Laboratory standard instrument provides phase displaced signals, either pulses or sinusoids, for checking

and calibrating phase shifting networks, oscilloscope sweeps, phase meters and

other instruments where separation of periodic signals is important. Phase displacement may be selected in steps of two electrical degrees over range of 360°.

--Authors' abstract.

E-1061 Ikegami, F. , Influence of an atmospheric duct on microwave fading. Institute of

Radio Engineers, N. Y. , Transactions on Antenna and Propagation, 7( ):252-

257, 1959. (Unchecked) --The results of continuous observation of a duct carried

out utilizing a tower 312 meters high are presented together with those of measurements of microwave fading conducted simultaneously. The variation of duct

height with time, as well as the influence of the duct on fading for a horizontal

and an oblique propagation path, are investigated in detail. A ray-theoretical

analysis is given, indicating that fading may be attributed to the divergence or the convergence of radio waves and to the interference of two or more rays,

caused by existence of a duct, or, more generally, of nonlinear M-profile. A

comparison of calculation with experimental results shows that many of the characteristics of microwave fading are well explained by means of this interpretation.

—Author's abstract.

E-1062 Joint Technical Advisory Committee (IRE-RTMA), Radio spectrum conservation : program of conservation based on present uses and future needs . A report of the

Joint Committee of the Institute of Radio Engineers and the Radio-Television

Manufacturers' Association. N. Y. , McGraw-Hill, 1952. 221 p. Figs., bibliog.

p. 199-208. DLC (HE8667. J65)--This survey gives an evaluation of the radio

spectrum related to industrial, scientific and medical use. Allocations of different frequency bands are suggested, and some general characteristics of propagation at different frequencies are discussed in relation to meteorological conditions in the ionosphere and troposphere. (See ref. E-10)--W. N.

E-1063 Joint Technical Advisory Committee (IRE-RTMA), Radio transmission by ionospheric and tropospheric scatter. Pt. 1. Ionospheric scatter transmission . Institute

of Radio Engineers, Proceedings, 48(l):4-29, Jan. 1960. 23 figs. , tables, 83

refs. Pt. 2. Long range tropospheric transmission. Ibid., p. 30-44. 10 figs. , tables, 43 refs. "This- is a supplement to the earlier comprehensive report, Radio

spectrum conservation, issued by the Joint Committee of the Institute of Radio

Engineers and the Radio Television Manufacturers Association, (abstracted

separately), published N. Y. , McGraw-Hill, 1952." DLC -The ionospheric and

tropospheric scatter communication techniques are summarized individually; the

present knowledge on ionospheric propagation theories, instrumentation practice,

etc. , including frequency allocation, is treated in the first part. Second part

deals with the same as applied to the troposphere. (Met. Abs. 12. 8-113) --W. N.

E-1064 Katz, Isadore (Appl. Phys. Lab. , Johns Hopkins Univ. , Silver Spring, Md. ), Radar reflectivity of the ocean surface for circular polarization . IEEE Transactions on Antennas and Propagation, N. Y. , ll(4):451-453, July 1963. 2 figs. , 4 refs. , 16 eqs. DLC --The vector model of rough sea reflectivity is extended to include

circular polarization. Some of the problems to which the technique discussed,

are applicable include: (1) Prediction of coverage pattern of a search radar; (2)

discrimination against rain clutter up to 17 db and (3) airport radar tracking of

aircraft during storms. --W. N.
269

Kiely, D. G. and Carter, W. R. , An experimental study of fading in propagation

at 3 cm wavelength over a sea path. Institution of Electrical Engineers, London,

Proceedings, 99(58):53-60, March 1952. 8 figs. , 4 tables, 8 refs. DLC--The

paper describes an experimental study of fading in propagation over a sea path

within the radio horizon at a wavelength of 3 cm carried out between July 1950

and Jan. 1951. Horizontal polarization was used. The object of the investigation was to record the general fading characteristics (i. e. depth, duration and

frequency of occurrence) for summer, autumn and winter and to present the results

in such a form that the effects of fading on the operational ranges of radar experiments would be readily appreciated. An initial assessment of the transmitter

power required for reliable operation of a beacon under given conditions has also

been made. --Authors' abstract.

Kirby, R.C. and Little, C.G. , Conference on Arctic Communication . U.S. National Bureau of Standards, Journal of Research, Sec.D, 64(l):73-80, Jan. /Feb.

1960. DWB, DLC--A Conference on Arctic Communication was sponsored by the

Central Radio Propagation Laboratory and held at the Boulder Laboratories, National Bureau of Standards, March 3 to 6, 1959. Approximately 275 persons

attended, representing universities and research, consulting, and engineering

organizations, as well as the Department of Defense and other government

agencies. Foreign representation included Canada, Great Britain, SHAPE Air

Defense Technical Center, and (by communication) the Norwegian Defense Research Establishment. The objectives of the conference were to review the re- sults of recent arctic radio research and to discuss current research and operational problems. The opening session was devoted to a review by various

laboratories of their arctic research programs. Forty-six papers were then pre- sented at four open and two classified sessions. The conference closed with an informal discussion period, during which three panels, devoted respectively

to communication at VLF to LF, HF to VHF, discussed fields requiring further

research. The full proceedings of the conference will not be published, as it is

expected that appropriate papers will be published in technical journals by individual authors. (Met. Abs. 14. 8-137) --Authors' abstract.

Kitchen, F. A. ; Joy, R.R.and Richards, E.G. (all, Admiralty Signal and Radar

Establishment, Portsdown, Cosham), Influence of the semi-permanent low level ocean duct on centimeter wave scatter propagation beyond the horizon . Nature,

London, 182(4632): 385-386, Aug. 9, 1958. 3 figs. , 7 refs. DWB--A number of

observations conducted since 1949 by the Admiralty Signal and Radar Establishment showed the extra-diffraction signal levels relative to free space to be 10-15

db lower at 10, 000 Mc than at the corresponding levels at 3000. Some characteristic interference patterns are plotted. There were no marked discrepancies

when the measured free space level of the contributing lobes, rather than the

theoretical values, were used. --W. N.

Koch, J. W. ; Harding, W. B. and Jansen, R.J. (Nat'l. Bur. of Standards, Boulder,

Colo.), Fading rate recorder for propagation research. Electronics, N. Y. , 32(51):78-80, Dec. 18, 1959. 3 figs. , photo, 3 refs. DLC -Continuous, simultaneous recordings of radio signal strengths and fading rates are needed in radio

propagation research. An instrument is discussed which provides strip-chart re- cordings of fading rates from almost zero cps up to 300 cps, and which provides

a means for comparing average fading rates for various propagation conditions

and transmission frequencies. --Authors' abstract and P. A.K.
270

E-1069 Krevsky, Seymour (RCA Surface Communication Systems Labs. , N. Y.),

HF and VHF radio wave attenuation through jungle and woods. IEEE Transactions

on Antennas and Propagation, N. Y. , 11(4): 506-517, July 1963. Fig., table,

7 refs. , 3 eqs. DLC --Extension of Stratton and Wheeler's theory is applied to propagation experiments in New Guinea. The spread of typical physical constants at 3 Mc and at 30 Mc are tabulated and the upper and the lower limits are plotted. --W. N.

E-1070 Kuperov, L.P. , Kratkosrochnoe radioprognozirovanie na radiolinii o. Diksona - Moskva v navigatsiiu 1958 g. (Short range radio forecasting on the Dickson

Island-Moscow radio path during the 1958 navigation period. ) Problemy Arktiki

i Antarktiki, Leningrad, No. 1:119-, 1959. DWB, DLC --From Aug. to Nov. 1958

O.L.Solovskii and L. A. Iudovich of the Dickson Island Observatory, carried out

short range forecasts of the passage of short radiowaves along the Dickson IslandMoscow route. Four 6-hr forecasts were made daily. The forecasts were made

according to the method developed in the Arctic and Antarctic Institute. During

Oct. -Nov. the verification of forecasts of non-passage of the waves was 86.8%;

the verification of recommendations of operating frequencies was 89%. --I.L.D.

E-1071 Lewin, L. , Diversity reception and automatic phase correction. Institution of

Electrical Engineers, London, Proceedings, Pt. B, 109(46): 295-304, July 1962.

12 figs. , 8 eqs. DLC--The interference between the direct ray and a ground

reflected ray gives rise at the receiver of a communication link to a sinusoidal

field pattern in the vertical plane consisting of nodes and maxima. The position

and pattern w wavelength of this field depend on the receiver and transmitter

heights and spacing and on propagation conditions in an effective curvature parameter, C. This parameter varies in time and is the cause of most fading at a

single antenna. Its upper limit, which may be as high as 2. 5 for a small percentage of the time, determines minimum antenna heights for line-of-sight trans- mission under extreme conditions. C is normally about 3/4. Its range of variation determines the optimum spacing of a pair of diversity antennae, and suitable

design formulas are given. Experiments using a pair of mirrors, a varying transmitter frequency, and photographs of osolograph traces indicate an extreme lower

value of C over water of -1. 5. A moving film display shows that conditions can

vary rapidly from minute to minute, although at other times the display is steady

for hours at a time. An automatic phasing junction has been designed for insertion in the feed from two diversity antennas, the drive for the phasing element

being taken from the receiver. A combined signal nowhere smaller than the

greater of the received signals is obtained from the combining element, and when

the diversity spacing is chosen with regard to the extreme values of curvature obtained on the path, an excellent overall response is ensured. Some preliminary

figures are given for the performance of an improved combining network and phase

control apparatus operating in conjunction with a height - diversity microwave

system over a 69 mi overwater path. --Author's abstract.

E-1072 McPetrie, J.S. and Saxton, J. A. , Diffraction of ultra-short waves. Nature,

London, 144(3649): 631, Oct. 7, 1939. Table, 3 refs. DLC --In this set of ex- periments with 3 m waves, the transmitter was located at a fixed position, about

200 yds from the edge, whereas the receiver was moved to several locations of a slope at Dunstable Downs, England. It was found that the vertical electric field

increased relative to its horizontal equivalent when the receiver was moved down

hill into the shadow. The results presented in a table are discussed. (See E-32)

--W. N.
271

E-1073 Ortwein, N. R. , An annotated bibliography of literature pertinent to tropospheric

scatter propagation, 1945-1957. U.S. Navy Electronics Laboratory, San Diego,

Calif., Research Report No. 858, Aug. 4, 1958. 28 p. 18 refs. --The bibliography

includes a total of 126 references (of which 77 are annotated) arranged chronologically in alphabetical order by the authors' names. The brief introduction is fol- lowed by individual summaries of theoretical and experimental works. An author

index, but no subject index, is given. --W. N.

E-1074 Ortwein, N.R.andVoss, P.L. (both, U.S. Navy Elect. Lab. , San Diego, Calif. ), A study of the oceanic duct between San Diego and Hawaii at 445 Mc and 220 Mc.

Navy Science Symposium, 5th, Annapolis, April 1961, Proceedings, Vol. 3, pub.

1961. p. 823-833. 6 figs. DWB (359 N327pr) -Extensive and persistent temperature and refractive index inversions were found in the trade wind areas. These

are sharp enough to trap VHF signals and propagate them to extreme ranges. The

characteristics of the signals received ground to ground, the effect of holes in the

duct, and some anomalies of the attenuation rate are discussed. The radio meteorological data given indicate the necessity of a continuous duct between terminals

in order to obtain ground to ground, ground to air, or air to air contact. On the

other hand, when the duct is continuous the radio data indicate the lack of the at- tenuation with distance which would be expected. Since the duct is not limited

in the horizontal direction, the absolute signal strength would be expected to de- crease at least as fast at inverse distances. This is apparently contradicted by

the presence of the signal plateaus. A possible explanation is suggested. (Met.

Abs. 13. 10-292) -E.Z.S.

E-1075 Pivarunas, Frank A. , Tropospheric and Ionospheric scatter propagation in the

transition zone . U.S. Air Force Cambridge Research Center, Bedford, Mass.,

Technical Report, No. 59-136, April 1959. Figs., 15 refs. (Unchecked) -There

is a zone of receiver distances in which a transition from tropospheric to ionospheric scatter propagation for the received signals can and does take place for frequencies generally used for ionospheric scatter propagation (between about 35

and 60 Mc). The diurnal and seasonal variations of the median signal levels in

each mode determine when and where the signal levels of both modes are within

a few db of each other so that the transition region can occur. Since the fading

rates peculiar to the ionospheric scatter mode are different from those of the

tropospheric scatter, the transition region is readily recognized by the superimposed fading rates on signal level recordings. The scatter volumes for the transition zone are in the stratosphere for the tropospheric scatter mode. This may ac- count for some of the changes in tropospheric scatter signal characteristics as distance increases to reach the transition zone. A mode diversity system to improve reception of signals in this zone by using optimum beamwidths and orientations of the antennas used in transmitting and receiving was proposed. --Author's

abstract.

E-1076 Rice, Philip L. (Nat'l. Bur. of Standards, Boulder, Colo.), Tropospheric fields

and their long term variability as reported by TASO. Institute of Radio Engineers,

N.Y. , Proceedings, 48(6): 1021-1029, June 1960. 13 figs. , table, foot-refs.

DLC--This report presents data from long term recordings of radio field strength over a large number of propagation paths, and presents curves for predicting field

strength over a smooth earth for frequencies between 40 megacycles and 1000

megacycles per second. The basic data provided for the Television Allocations

Study Organization during 1957 and 1958 include recordings made in several parts

of the world and over various types of terrain and were supplied by numerous

sources. --Author's abstract.
272

E-1077 Ruina, J. P. and Angulo, CM., Antenna resolution as limited by atmospheric

turbulence . IEEE Transactions on Antenna and Propagation, N. Y. , 11(2):153-

161, March 1963. 5 figs. , 10 refs. , 28 eqs. DLC--The purpose of this theoretical examination was to determine the resolution capability of microwave

antennas as governed by the effects of the refractive index variations on the

phase and the amplitude of a radio wave propagating through the atmosphere.

--W. N.

E-1078 Samoilov, G.P. , DaTn ii priem televizionnvkh peredach. (Long distance reception of television broadcasts.) Moscow. Gos. izd-vo lit-ry po voprosam sviazi

i radio, 1957:199. 34 refs. , all Russian. (Unchecked) --In the first chapter,

after reviewing the mechanism of the propagation of meter waves, the author dis- cusses long distance and very long distance reception of television programs.

Chapters two through six deal with equipment for long distance reception and

techniques for improving reception. The final chapter discusses techniques and

possibilities of long distance television programs. --R. M.

E-1079 Sharpless, William M. , Measurement of the angle of arrival of microwaves.

Institute of Radio Engineers, N. Y. , Proceedings, 34(11) -.837-845, Nov. 1946.

8 figs. , 3 refs. DLC--This paper describes a method of measuring the direction

from which microwaves arrive at a given receiving site. Data which have been

collected on two short optical paths using a wavelength of 3 1/4 centimeters

are presented to illustrate the use of the method. Angles of arrival as large as 1/2 degree above the true angle of elevation have been observed in the vertical

plane, while no variations greater than + 1/10 degree have been found in the

horizontal plane. These results indicate that radar directions for low angles of

elevation may be in error by several tenths of a degree during times when anomalous propagation conditions are present. Possible solutions to the problems

introduced by variations in the angle of arrival are suggested. --Author's abstract.

E-1080 Saxton, J. A. et al. (all, Radio Research Station, DSIR), Layer structure of the

troposphere: simultaneous radar and microwave refractometer investigations . Institution of Electrical Engineers, London, Proceedings, 111(2) :275-283, Feb.

1964. 8 figs. , 3 tables, 25 refs. , 23 eqs. DLC--A discussion is presented of

the manner in which layer type echoes may arise and be observed using a 10 cm

radar at vertical incidence; such echoes are due to variations in the gaseous

refractive index and not to water droplets in clouds or precipitation. Specular

reflection and scattering processes are compared and the conditions indicated

when an echo may be due to one or the other process, although the applicability

of the turbulence theories used to relatively thin layers needs to be established.

The results of the analysis are discussed in relation to data obtained from simultaneous soundings of the troposphere by radar and airborne microwave refractometers. Some comments are made regarding further experimental and theoretical

investigations of the fine structure of elevated layers. --Authors' abstract.

E-1081 Silberstein, Richard (U.S. Nat'l. Bur. of Standards, Boulder, Colo.), Tropospheric

effects on 6 Mc pulses . Institute of Radio Engineers, N. Y. , Proceedings, 46(12):

1968, Dec. 1958. 2 refs. DLC —Describes test of independent measurement of

the virtual height of echoes, conducted at Boulder, Colo. , over a 5. 2 km northsouth path. The mountainous area in west apparently caused the scatter with

fluctuations producing variable multipath interference of that part of ground wave

signal remaining when discriminated against by substituting the dipole with a

rotating vertical loop antenna1. --W. N.
273

Suzuki, M. , Experimental analysis of equivalent reflection coefficient of various

reflecting rough surfaces in microwave propagation. ETJ of Japan, 4:3-6, 1958.

(Unchecked) -The reflection coefficient is evaluated for various angles of incidence and types of surfaces and terrain with crop cover. —H. T. D.

Texas. Univ. , Austin. Electrical Engineering Research Lab. , Bibliography of

technical reports, publications, and theses. Feb. 1959-Feb. 1961 . Contract

Nonr 375(01) NR 371 032, Report No. 121, Feb. 28, 1961. 16 p. DWB, DLC--

This bibliography supplements Electrical Engineering Research Laboratory Report

No. 106 which presented a consolidated listing of publications of the laboratory

through 1958. The present report is specifically concerned with publications

covering 1959 and 1960. No effort was made to list informal reports of the memorandum or quarterly status variety except where significant technical information is involved. The bibliography lists serially, first, the technical reports of

sponsoring agencies. In addition to the title, the authors and the contract number are noted. The next group of titles are designated as technical publications.

Authors and publication sources are noted. The third grouping of titles is devoted to master's and doctoral theses. The bibliography is followed by a complete distribution list. (See ref. E-337)--M. B. G.

Ugai, Shigetaka, Statistical consideration of the structure of atmospheric re- fractive index. Reports of EC L, Japan, 7:253-289, Aug. 1959. (Unchecked)--

A 300 meter tower is employed to obtain 12 level samplings of the refractive

index gradient on an hourly basis over a two month period. These are compared

with radiosonde data obtained twice a day for the same period. The resulting

distribution of vertical refractive index gradient was found to be approximately

normal. The analysis is then extended to determine the resulting mean and

standard deviations from radiosonde data between 900 and 1000 mb levels on a monthly basis and for 8 geographical locations. --H.T. D.

Volland, H. , Comparison between mode theory and ray theory of VLF propagation.

U.S. National Bureau of Standards, Journal of Research, Sec. D, 65(4):357-361,

July/Aug. 1961. 4 figs. , 2 tables, 16 refs. , 12 eqs. DWB, DLC--It is shown

that the field strength according to mode theory and ray theory in the VLF band

are derivable from the same expression of the original vector potential, and the

result of one theory is the analytic continuation of the other one in another range

of convergence. In fact, both ranges of convergence overlap. Estimates of

these ranges are made and an example shows that within this overlapping region

(between distances of 300 and 2000 km) both theories give the same result. Using

this fact calculations of frequency spectra are possible which in the case of

white noise dipole show some similar features to measured frequency spectra of

lightning discharges. (Met. Abs. 14. 10-99) —Author's abstract.

Wait, James R. , Excitation of surface waves on conducting, stratified, dielectric clad, and corrugated surfaces. U.S. National Bureau of Standards, Journal

of Research, 59:365-377, Dec. 1957. 27 refs. DLC--An expression for the field

of an electric dipole located over a flat surface with a specified surface impedance Z is derived from the formal integral solution by a modified saddle point

method. Using the value of Z appropriate for a homogeneous conducting ground,

the general expressions reduce to those given by Norton. In this case the phase

of Z lies between and 45°. When the phase exceeds 45°, as it may for a

stratified ground, the radiated wave of the dipole becomes partially trapped to
274

the interface. This effect is most pronounced for an inductive surface where the

phase of Z is 90°, in which case the energy of the wave is confined within a small distance from the surface. Such inductive surfaces are a metallic plane

with a thin dielectric film or a corrugated surface. This unifying treatment provides a link between the surface waves of Zenneck, Sommerfeld, Norton, and

Goubau, and indicates that the phase angle of Z controls the extent to which

these waves may exist for a dipole excitation. --Author's abstract.

E-1087 Wait, J. R. and Murphy, Anabeth, Further studies of the influence of a ridge on

the low frequency ground wave. U.S. National Bureau of Standards, Journal of

Research, 61:57-60, July 1958. 4 figs. , foot-refs. DLC --Computations are presented in graphical form for the perturbation of a plane wave by a semicylindrical

boss on an otherwise flat ground plane of perfect conductivity. The height of the

ridge is comparable to the wavelength. This is an extension of earlier work on

the semielliptical boss. --Authors' abstract.

E-1088 Wait, J. R. and Conda, A.M., On the measurement of ground conductivity at VLF. Institute of Radio Engineers, N. Y. , Transactions on Antennas and Propagation, 6(3):273-277, July 1958. 3 figs. , 8 refs. , 21+ eqs. --The applicability

of the four electrode methods of measuring ground conductivity at VLF is discussed. The general theory is extended to include anisotropy in the substrata.

In view of the spurious coupling between the current and potential line in conventional configurations, an alternative array is proposed which is arranged so

that the inductive coupling is zero. A number of charts are computed which

facilitate the interpretation of the measured or apparent conductivity in terms

of a two-layer earth. --Authors' abstract.

E-1089 Wait, J. R. , Transmission and reflection of electromagnetic waves in the pres- ence of stratified media. U.S. National Bureau of Standards, Journal of Research,

61:205-232, Sept. 1958. 12 figs. , 15 refs. , eqs. DLC--A general analysis is

presented for the electromagnetic response of a plane stratified medium consisting of any number of parallel homogeneous layers. The solution is first developed

for plane-wave incidence and then generalized to both cylindrical and spherical

wave incidence. Numerical results for interesting special cases are presented

and discussed. The application of the results to surface wave propagation over

a stratified ground is considered in some detail. --Author's abstract.

E-1090 Wait, J. R. , Guiding of electromagnetic waves by uniformly rough surfaces . Pt. 1-2. Institute of Radio Engineers, Transactions on Antennas and Propagation,

Special supplement to Vol. 7, Dec. 1959. p. 154-168. 8 figs. , 35 refs. , eqs.

DLC--A simple derivation is given for the reflection of electromagnetic waves

from a perfectly conducting plane surface which has a uniform distribution of

hemispherical bosses whose electrical constants are arbitrary. The spacing between the centers of the bosses is taken to be small, which is the justification

for neglecting the incoherent radiation. The excitation of surface waves on the

rough surface is then discussed. It is indicated that to a first order, a rough

surface of the kind described here possesses an inductive surface reactance and

will support a trapped wave. The effect of finite conductivity of the bosses is to damp exponentially this trapped wave. In Pt. 2, using the model of a single

rough surface described in Pt. 1, the influence of curvature is considered. The

starting point is a residue series solution for a vertical dipole over a sphere with an arbitrary surface impedance. It is shown that the curvature has a profound in- fluence on the nature of the surface wave, although it uniformly approaches the

conditions for a plane boundary as the radius of curvature approaches infinity.

--Author's abstract.
275

E-1091 Wait, J. R. and Conda, A.M., Diffraction of electromagnetic waves by smooth

obstacles for grazing angles. U.S. National Bureau of Standards, Journal of

Research, Sec. D, 63(2): 181-197, Sept. -Oct. 1959. 8 figs. , 26 refs. , 42 eqs.

DLC--The diffraction of electromagnetic waves by a convex cylindrical surface is

considered. Attention is confined primarily to the region near the light shadow

boundary. The complex integral representation for the field is utilized to obtain

a correction to the Kirchhoff theory. Numerical results are presented which il- lustrate the influence of surface curvature and polarization on the diffraction pattern. Good agreement with the experimental results of Bachynski and Neugebauer

is obtained. The effect of finite conductivity is also considered. --Authors' abstract.

E-1092 Wait, J. R. , On the excitation of electromagnetic surface waves on a curved

surface. Institute of Radio Engineers, N. Y. , IRE Transactions on Antenna and

Propagation, AP-8(4): 445-448, July 1960. 2 figs. , foot-refs. DLC--The excitation and propagation of surface waves on a spherical inductive boundary are considered. The source is taken to be a vertical electric dipole. The circumferential

attenuation rates of the various modes are discussed where it is indicated that the

dominant mode is very similar to the trapped surface wave for a plane inductive

boundary. The results appear to conflict with those of Barlow, but are in sympathy with some numerical data of Elliott for the circumferential attenuation rate of

the dominant mode. --Author's abstract.

E-1093 Wait, J. R. , Survey and bibliography of recent research in the propagation of

VLF radio waves. U. S. National Bureau of Standards, NBS Technical Note, No. 58,

May 1960. 44 p. Bibliog. p. 14-44. Also issued in: International Scientific

Radio Union. Commission IV on Radio Noise of Terrestrial Origin. Amsterdam,

Elsevier, 1962. DWB (M(055) U585te)--The subject is discussed in terms of

theoretical studies, analyses of experimental data, recent applications of VLF

and suggestions for future work. The valuable bibliography which covers the

literature period 1919-1960 contains a total of 320 references classified individually and listed alphabetically by authors under the breakdown of 17 topics into

which the subject is divided. (Met. Abs. 14. 2-126) --W. N.

E-1094 Wait, J. R. , On the theory of mixed path ground wave propagation on a spherical

Earth. U.S. National Bureau of Standards, Journal of Research, Sec. D, 65(4):

401-410, July/Aug. 1961. 2 figs. , 20 refs. , 51 eqs. -The problem formulated concerns the mutual impedance between two vertical dipole antennas A and B

located near the surface of a spherical smooth earth. The path between A and B

is made up of a number of homogeneous segments where the surface impedance

is constant. Various formulas are developed, for two- and three-section paths,

which are suitable for computation. Certain limiting cases are discussed and

where possible, a physical interpretation of the results is given. Comparisons

with previous work are made. --Author's abstract.

E-1095 Wait, J. R. , Electromagnetic waves in stratified media. N. Y. , Macmillan,

1962. Price $15. 00. 372 p. Figs., tables, refs. (International Series of

Monographs on Electromagnetic waves, Vol. 3). CU-S, DLC. Review by

H. J.Hagger in Physics Today, N. Y. , 17(4):76, April 1964. -This book is intended to be used as a reference. Though basically of a theoretical nature, numerous

numerical examples and references to experimental data are included. The introductory chapter contains references to supplementary reading. Ch. II contains a
276

general analysis for the electromagnetic response of a plane stratified medium

consisting of any number of parallel homogeneous layers. In Ch. Ill, the reflection of electromagnetic waves from planar stratified media is discussed. Ch. IV

considers the oblique reflection of plane electromagnetic waves from a continuously stratified medium. The basic theory of wave propagation around a sphere

is given in Ch. V. In Ch. VI, a self contained treatment of the waveguide mode

theory of propagation is presented. In Ch. VII, the mode theory of VLF propagation is considered from another point of view. In Ch. VIII, the influence of a steady or d. c. magnetic field on reflection from ionized media is considered in

some detail. In Ch. IX, approximate techniques for solving the VLF modal

equation are described. In Ch. X, the mode theory of propagation of electromagnetic waves at extremely low frequencies (1. - 3000 c/s) is considered. In Ch. XI, the physical connections between mode and ray theory are developed.

In Ch. XII, the theory of propagation in a spherically stratified medium is considered. --E. Z. S.

E-1096 Watt, A.D. ; Coon, R.M.; Maxwell, E.L. and Plush, R. W. , Performance of

some radio systems in the presence of thermal and atmospheric noise. Institute

of Radio Engineers, N. Y. , Proceedings, 46(12): 1914-1923, Dec. 1958. 20 figs.,

36 refs. , 6 eqs. DLC--The performance of several basic types of communication

systems are determined experimentally and in some cases theoretically, under

typical conditions with steady or fading carriers, and in the presence of thermal

and atmospheric noise. The relative efficience of various carriers and the interference factor of various types of noise are found to be dependent upon the characteristics of the particular communication system as well as the characteristics

of the carrier and noise themselves. Methods are considered for calculating

errors expected from a given system, based upon the amplitude distribution of

the noise envelope. --Authors' abstract.

E-1097 Wong, Ming S. (AFCRC Propagation Lab. , Bedford, Mass.), Refraction

anomalies in airborne propagation. Institute of Radio Engineers, Proceedings,

46(9): 1628-1638, Sept. 1958. 16 figs. , foot-refs. , 5 eqs. DLC -Propagation

at 250-10,000 Mc of ten encounters dense fadings, radio holes, antiholes or radio ducting. These anomalies are portrayed by ray tracings using a differential

analyzer which solves the simplified ray equation

dx2 h

Both hypothetical prototype and complex measured refractive index profiles of the

atmosphere are used for the analog computation of the ray tracings which are interpreted to explain refraction anomalies in radio wave propagation, and are compared with signal strength measurements. They involve divergence of rays, and

concentration and crossing of direct rays in multipath transmission. Resulting

radar angular and range errors are shown, as are spatial variations of elevation

angles of arrival of interfering rays at the points where they cross, corroborating

radio astronomical data on angular deviation of stars. (Met. Abs.

--From author's abstract.
277

ANONYMOUS

E-1098 Arctic Radio Communication Conference . U. S. National Bureau of Standards,

Technical News Bulletin, 43(11):213-217, Nov. 1959. --R.C. Kirby (Boulder

Labs.) served as conference chairman over the some 250 scientists, engineers

and other professionals from U.S.A. and abroad, assembled at U.S. National

Bureau of Standards Laboratories at Boulder, Colo. , March 4-6, 1959. A sum- marized report of the several aspects, involved in ionospheric as well as tropospheric radio wave propagation in the Arctic, are given. --W. N.

E-1099 Effect of sub-refraction on radar range . Marine Observer, 27(176): 114-116, April

1957. DLC--W. BURGER inquired whether radar horizon at sea can be reduced to 1-3 mi as a result of sub-refraction. R.F.JONES regarded this as impossible.

CAPT. WYLIE agreed. (Met. Abs. 8 J-159)--C. E. P. B.

E-1100 Forward scatter of radio waves. Pt. II. Tropospheric forward scatter. Pt. HI. Causes and theories of propagation by scattering due to turbulence. U.S. National Bureau of Standards, Technical News Bulletin, 40(2):24-29, Feb. 1956.

7 figs. , 9 refs. --First part deals with ionospheric scattering. Pt.II deals with

work on tropospheric scatter propagation which began Jan. 1949. Instrumentation and facilities involved in the experimental transmissions are described

briefly. Pt.III is devoted to the causes and theory of scattering due to turbulence in the troposphere, as well as in the ionosphere. Some of the results obtained are mentioned. --W. N.

E-1101 Inauguration de la liaison hertzienne experimentale Paris - Nancay de la Compagnie Generate d'Electricite. (Inauguration of an experimental radio link between Paris and Nancay created by the Compagnie Generate d'Electricite.

)

Onde Electrique, 40(400/401): 544-545, July/Aug. 1960. 2 figs. DLC--Brief

report on experimental scatter communication link between Paris and Nancay,

a distance of 180 km. The purpose of the link is to investigate equipment

operating in the 900 Mc band. Such equipment is to be installed in the AlgiersSetif-Constantine-Bone system in 1961. The transmitting station in Paris has a 2 kw transmitter, a 4 cavity klystron amplifier, and a parabolic antenna 10 m in

diameter. A double or quadruple diversity receiving system, with two 10 m

parabolic antennas, is situated at Nancay. The link has a capacity of 84 telephonic channels.

E-1102 Konferentsiia po voprosam dal'neqo rasprostraneniia UKV. (Conference on problems of forward scatter of ultrashort waves. ) Radiotekhnika, Moscow, 12(4):

67-68, April 1957. Transl. in Radio Engineering, N. Y. , 12(4):80-83, 1957. DLC--

Report of a conference in Jan. 1957 on forward scatter of ultrashort waves which

was sponsored jointly by the A.S.Popov Society, the All-Union Scientific Council

for Radio Physics and Radio Engineering, find the Institute of Radio Engineering

and Electronics. Five papers were devoted to problems in tropospheric scatter. P.P.Biriulin's paper dealt with an integral equation for the vector potential of the

scatter field in a medium with fluctuating permittivity. V. A.Zverev described

methods of computing the mean intensity of the scatter of radio waves by random

irregularities. D. M. Vysokovskii's paper was concerned with a critical analysis

of the derivation of the general formula for the effective scattering volume in the
278

troposphere. The paper by A. A.Semenov and G. A. Karpeev described the results

of an experimental investigation of rapid fluctuations in the amplitude of signals

reflected from two fixed reflectors and received by two spaced antennas. L.Ia.

Kazakov and A. N. Lomakin devoted their paper to a survey of the principle of performance and design of a radio refractometer for measuring the irregularities in

permittivity. A. N. Kazantsev surveyed the materials of the 8th Plenary Confer- ence on Ionospheric Forward Scatter of Meter Waves. He also dealt briefly with

the utilization of meteor trails in this form of communication. In his paper,

Ia.L. Al'pert described results of a theoretical analysis of ionospheric scatter

using a correlation function of a particular form. B. N. Gershman derived the ef- fective area of ionospheric scatter taking into account the turbulent shifting of

ionized gas. M. V.Boenkov surveyed the problems of using forward scatter of

6-10 meter waves by reflection from layers of the ionosphere. The papers by

S. F. Mirkotan and L. A. Drachev, and by Iu. V. Berezin described the investigation of the irregular structure of the ionosphere using frequency diversity and re- cording the variations of the phase path of the reflected signal. The reports by

V. A.Bubnov, A. I. Khachaturov and S.I.Sotnikov were devoted to various cases

of the long distance reception of meter waves, foreign television programs, etc. --R.M.

E-1103 Measurement of service area for television broadcasting . U.S. National Bureau

of Standards, Technical News Bulletin, 41(8):113-115, Aug. 1957. 5 figs. , table, ref. DLC--Some of the advantages of the new method of area concept of

service as developed by NBS, are discussed comparatively with the contour

concept method heretofore used. --W. N.

E-1104 NBS establishes radio refractive data center. Electronics, N. Y. , 34(49):28,

Dec. 8, 1961. DWB, DLC -The National Bureau of Standards has established

a Radio Refractive Index Data Center at its Boulder, Colo. Lab. to assist

studies of radio propagation in the earth's atmosphere. Data on meteorological

parameters affecting refractivity is sent to Boulder by more than 300 weather

stations and ships around the world. More than seven million punched card

records have been prepared. The center can compute index profiles for certain areas or make cards available. (Met. Abs. 14. 7-118) --S. N.

E-1105 Radar and meteorological conditions. Marine Observer, London, 33(202):212-

214, Oct. 1963. Table. DWB, DLC -The following aspects of anomalous propagation of radar waves, as influenced by the refractive index of the atmosphere,

are discussed, namely: sub-refraction, superrefraction, and ducting, second

or multiple trace echoes, and atmospheric discontinuities. --I.L.D.

E-1106 Radio waves round corners. Discovery, London, 23(7): 5-6, July 1962. DLC--

A brief note on a successful experiment carried out by IBM engineers in transmitting low power microwaves using the principle of knife edge diffraction by

a mountain ridge. --R. B.

E-1107 The Radio Research Station. Slouah. Nature, London, 181(4624): 1642-1643,

June 14, 1958. DWB, DLC -When the Radio Research Board visited the Research Station, Britain, on May 20, 1958, the research programs now underway

at the station were shown. The major research work is intended to help radio
279

services in the area of field communication. Substations connected with the

main stations are quoted. Above all, a new technique for studying high fre- quency radio propagation was displayed. They have developed also a new

microwave refractometer for exploring meteorological conditions in the troposphere and relating these to the associated radio phenomena. --N. N.

E-1108 Tropo-scatter antenna cuts installation costs . Electronics, N. Y. , 34(46):149,

Nov. 1961. DWB, DLC--The antenna developed by the Boeing Co. is claimed

to operate up to 500 mi without signal boosters. Available in 30, 60, and

120 ft reflector widths, the parts (3/4 usual) when color coded, permit assembly

of a 60 ft antenna in 50 hr by unskilled non-English speaking men. (Met. Abs.

13. 8-228) --W.N.

E-1109 Tropospheric scatter propagation: 200 mi transmission on frequencies in the

UHF band. Wireless World, London, 61(6): 253-254, June 1955. Fig. , 2 refs.

DLC--The turbulent troposphere is visualized as made up of a number of spherical blobs in which the dielectric constant differs from that of the medium as a whole. These scatter the energy, mainly forward, and are usable by highly

directive beam aerials up to 200 mi. Practical applications are described.

(Met. Abs. 8J-115)»C.E.P.B.

E-1110 A tropospheric scatter system. Point to Point Telecommunications, 3(l):20-28,

Oct. 1958. 4 figs. , ref. DLC--For two years the Marconi Co. has operated an experimental tropospheric scatter system to assess the potentialities of this

medium of communication and to provide data on attenuation and fading characteristics. A full scale scatter circuit was set up between Start Point in Devon

and Galleywood, near Chelmsford, in Essex, a distance of 200 mi. Measurements are being made using a multichannel telephony system. Frequency modulation is being used and tests using single sideband modulation in conjunction

with a linear transmitter are being made to provide comparative data. Wideband

transmissions are also to be made to assess the possibility of using channel

capacities of up to 600 telephone circuits. Television pictures are also to be

transmitted over the link. Some findings to date are evaluated. The route and

profile of the link are shown. --R. M.
280

AUTHOR INDEX

Aslakson, Carl I. , E-89

Abbott, Richard L. , E-441, 684

Abild, Bruno, E-151, 152, 347

Abraham, L. G. , Jr. , E-793

Adams, R.T. , E-947

Aden, Arthur L. , E-180

Aida, Kazuo, E-571

Akima, Hiroshi, E-685, 686

Akita, Kin -Ichiro, E-464, 639, 904

Aksenov, V.I. , E-520, 794

Albright, W. G. , E-248

Al'pert, Ia.L. , E-181

Altman, Frederick J. , E-348-351

Altovsky, V. , E-367

Ament, W.S. , E-182, 352, 581

Ames, L. A. , E-267, 268, 353, 486,

603, 687, 1043

Ammerman, C. R. , E-257

Anastassiades, M. A. , E-521, 874

Anderson, J.Bach, E-960

Anderson, Loyd J. , E-153, 183-185,

269, 378, 522, 593, 681

Anderson, W.L. , E-604, 688

Andrieux, G. , E-689, 717

Angell, B.C. , E-523

Angulo, CM. , E-1077

Anway, Alan C. , E-961

Aono, Yuichiro, E-270

Arenberg, A. G. , E-436, 504

Arendt, P. R. , E-962

Armand, N. A. , E-795, 796, 875, 876

Arnold, P. , E-151

Arnold, P. N. , E-14

Arsac, Jacques, E-877

Arsen'ian, T.I. , E-878

Arvola, William A. , E-187, 400, 437

Asai, Jun-ichi, E-524, 690

Ashwell, G.E. , E-408

Ashwell, P. C. , E-148

Ataev, O. M. , E-770

Atkinson, N. W. , E-963

Atlas, David, E-605, 606

Attwood, Stephens., E-87

Austin, J. M. , E-33

Badcoe, S. R. , E-588

Baeyer, H.J. , E-607

Baldinger, E. , E-124

Balzer, Martin, E-260

Bankston, L. , E-879

Barghausen, A.F. , E-271, 797, 964,

965

Barghausen, A. F., E-1044

Barlow, Howard Everard Monteagle,

E-880

Barrows, E.C. , E-939

Barsis, A.P. , E-235, 272, 319,

354. 355, 798-800, 881,

882, 965, 1045, 1046

Bartels, G. , E-172

Barton, John H. , E-883

Bass, F.G. , E-533, 608, 644, 645,

691, 801, 884, 966

Basu, Amal, E-438

Bauer, John R. , E-525

Bauer, L.H. , E-439, 802

Baur, K. , E-440

Bayot, R. , E-692

Bazer, J. , E-885

Beach, C. D. , E-967

Bean, Bradford R. , E-186, 236, 237,

273, 356, 441-443, 526, 609-

615, 693-698, 803-808, 886,

887, 968-970, 996, 1017, 1047

Beard, C.I. , E-357, 444

Beckmann, B. , E-154

Beckmann, Petr, E-445, 527, 699,

700, 1048

Belkina, M.G. , E-547

Bell, M.B. , E-1032

Bellaire, F.R., E-187

Bellman, Richard, E-701

Benoliel, I. , E-809

Berg, Eduard, E-446

Bergmann, Peter G. , E-38

Berry, J. A. , E-251

Beyers, Norman J. , E-447, 604, 688

Bickelhaupt, M.H. , E-680

Bigler, Stuart G. , E-528

Birnbaum, George, E-90, 125, 274

Blake, Lamont Vincent, E-888

Blomquist, Ake, E-702

Bogle, A. G. , 1049

Boithias, L. , E-703, 889

Bolgiano, R. , Jr. , E-529, 616, 704,971

Bolljahn, J. T. , E-358

Bonavoglia, Luigi, E-530

Booker, H. G. , E-39, 56, 91, 92, 126,

275, 448, 890, 1053

Boudouris, George, E-449, 972

Bowhill, S. A. , E-810

Boyd, J. E. , E-93, 127

Braam, G. P. A. , E-1033

Braaten, A.M., E-55, 179

Bradshaw, J. A. , E-793, 973
281

Braham, Roscoe R. , Jr. , E-531

Brandejs, Stanislav, E-94

Braude, S.Ia. , E-532, 533, 653, 654,

811, 891

Bray, W. J. , E-276

Bremmer, H. , E-71, 95, 188, 238,

534, 705, 892, 1050

Brilliant, Martin, E-1051

Britt, CO. , E-264

British Institution of Radio Engineers,

London, E-277

Brocks, Karl, E-128, 155, 278

Broussaud, G. , E-706

Brown, F. B. , E-93

Brown, J. , E-880

Browne, Ian C. , E-189

Browne, L.C. , E-148

Bugnolo, Dimitri S. , E-617, 707

Bull, Gunther, E-708

Bullington, Kenneth, E-47, 96, 97,

190, 279, 280, 450, 618

Burrows, Charles R. , E-17, 18, 87, 893

Bussey, Howard E. , E-274

Buxton, A.J. , E-535

Byam, L.A. , Jr. , E-lll, 191

Byatt, W.J. , E-812

Cabessa, R. , E-709

Cahoon, B. A. , E-442, 694, 698, 805,

1047

Cahoon, B.A„ E-443

Campen, Charles F. , Jr. , E-281, 369, 484

Capps, F. M. , E-253, 390, 1046

Carl, Helmut, E-359

Carlson, G. , E-557

Carr, Thomas R. , E-360

Carroll, Thomas J. , E-239, 240, 282,

361, 953

Carter, W. R. , E-1065

Carzan, C. , E-746

Casini, G. , E-813

Cassedy, E.S. , E-814

Cayzac, J. , E-689, 717

Chapman, C. W. , E-839

Chapman, J.H. , E-374, 451

Chen, Y. Y. , E-1056

Chernov, Lev Aleksandrovich, E-710

Cherenkova, Elena Lazarevna, E-536

Cheydleur, Raymond D. , E-98

Chisholm, J.H. , E-283, 362, 537,

619, 815, 894

Christall, F. I. , E-156

Chu, Chiao-Min, E-363

Churchill, Stuart W. , E-363

Clara, Jose Maria, E-364

Clarke, R.H. , E-974, 1052

Clarke, Robert F. , E-365

Clavier, Andre G. , E-366, 367

Clemmow, P.C., E-192

Clinger, A.H. , E-711

Clutts, C.E. , E-816

Cole, Allen E. , E-281

Collier, James S. , E-284

Colloque International sur les

Problemes d'Actualite dans la

Propagation des Ondes Radioelectriques, Paris, Sept. 1956,

E-452

Colwell, R.C., E-13, 20-22, 25, 28

Conda, A.M., E-1088, 1091

Conference on Radio Meteorology,

Univ. of Texas, Austin, Nov.

1953, E-193

Coon, R.M. , E-1096

Cornell University. School of Electrical

Engineering, E-99, 129-132, 157

Comford, E.C. , E-79

Coroniti, S.C. , E-453

Cosgriff, R.L. , E-564

Cowan, Leslie W. , E-194, 195

Craig, Richard A. , E-40

Crain, Cullen Malone, E-100-102,

158, 159, 196-198, 241, 285,

368, 374, 1053

Crawford, Arthur B. , E-23, 24, 41,

160, 458, 620, 895

Crysdale, J.H. , E-286

Cubitt, J. D. , E-156

Cunningham, Robert, E-369, 484

Das, P.M. , E-454

Dattan, W. , E-72

David, P. , E-975, 976

Davids, H.H. , E-817

Davidson, David, E-287

Davies, H. , E-73

De, A.C., E-454, 621

Deam, A. P. , E-158, 196, 288, 622,

896, 948

de Belatini, P. CM., E-623

de Bettencourt, J. T. , E-275, 283

Decino, Alfred, E-18

Decker, M.T. , E-271, 736, 1044,

1054

de Jong, A. , E-818

Denisov, N. G. , E-538, 624

Denman, Eugene D. , E-712

Dennis, Arnett S. , E-819, 897

Deppermann, K. , E-242

De Vault, G. P. , E-812

Dezerega, Bartolome, E-898
282

Dickson, F.H. , E-199, 286

Dinger, Harold E. , E-539

Dixon, J.M. , E-820

Dockes, J. , E-713

Doherty. L.H. , E-49, 200, 204, 625,

626, 977

Dolukhanov, M.P. , E-161, 455, 627

Domb, C. , E-48

Domingue, Jules C. , E-674

Dougherty, H.T. , E-308, 391, 1055

Doundoulakis, George, E-389

Drimmel, Julius, E-978

Dropkin, Herbert A. , E-540

duCastel, Francois, E-541, 542, 628,

703, 714-716, 899-901

Ducot, C. , E-689, 717

Durkee, A.L. , E-57, 280

Dutton, E.J. , E-695, 806, 821, 822,

968

Eccles, W.H. , E-7

Eckart, Gottfried, E-289, 543

Eckersley, T.L. , E-15

Edinger, James G. , E-823

Egli, J.J. , E-199, 286, 456

Eklund, F. , E-558

Elder, P. H. , E-800

Englund, Carl Robert, E-23, 24

Epstein, Jess, E-201, 370

Essen, L. , E-164

Evans, H. W. , E-635

Evdokimov, M. A. , E-544

Fagioli, —, E-813

Fainberg, J. , E-814

Fannin, B. M. , E-288, 371, 457, 604,

788

Fast, N. , E-879

Fehlhaber, L. , E-887, 913

Feinberg, E.L. , E-181, 563, 629,

761, 824

Feinstein, Joseph, E-133, 243, 244,

290

Felix, M.O. , E-535

Felsen, L.B. , E-718

Fersenheld, R.A. , E-545

Fenton, Lawrence F. , E-719

Ferrell, E.B. , E-17

Fickeissen, Omar O. , E-89

Filipp, N. D. , E-825

Fine, H. , E-162, 202, 245

Finney, R. G. , E-630

Flavell, R.G. , E-902

Flecher, Robert D. , E-35

Flock, W.L. , E-546

Flood, Walter A. , E-439

Florman, Edwin F. , E-291, 720

Fok, Vladimir Aleksandrovich, E-42,

103, 372, 547

Foot, J.B.L. , E-523, 826

Ford, L.H. , E-43, 44

Forest, A. , E-692

Forsgren, K.H. , E-147

Fostoff, B. , E-721

Fowler, C.S. , E-408

Franceschetti, Giorgio, E-979

Frank, V.R. , E-969

Frantsesson, A. V. , E-668

Franz, Walter, E-242, 246

Freeman, J. A. , E-1056

Freeman, J. J. , E-903

Friedman, Bernard, E-134

Friend, Albert W. , E-20-22, 25, 29, 37

Friis, H.T. , E-458

Froome, K. D. , E-164, 292

Frost, C.E. , E-650

Frundt, H. J. , E-247

Fuji, Yoshihisa, E-551

Fujikawa, Masatoshi, E-524, 690

Fukushima, M. , E-163, 311, 730, 904

Funakawa, Kenji, E-905

Furutsu, Koichi, E-293, 373, 459,

631, 906, 980, 981

Gallet, R.M. , E-610

Gangopadhayaya, M. , E-454

Garner, W. E. , E-539

Gast, E. , E-164

Gates, D. M. , E-982

Geiger, G.V. , E-722

Gerhardt, J. R. , E-69, 101, 102, 159,

196, 241, 261, 374, 480

Gerks, Irvin H. , E-135, 294, 375, 907

Germany. Deutscher Wetterdienst in der

U.S. Zone, E-136

Gerson, Nathaniel Charles, E-58, 453

Ghose, Rabindra Nath, E-223, 248

Ghosh, S.N. , E-827

Gjessing, Dag T. , E-1034, 1035

Gibbs, W.J. , E-249

Gibson, Theodore W. , Jr. , E-104

Ginzburg, V.L. , E-181

Glenn, A.B. , E-908

Goliashov, A.V., E-983

Golitsyn, G.S. , E-950

Golubtsov, M.G. , E-768

Goodman, S. J. , E-815

Gorbach, V. I. , E-653, 654

Gordon, William E. , E-59, 91, 92,

295, 448, 909
283

Gorelik, G.S. , E-376

Goss, R.N. , E-407

Gossard, Earl E. , E-183-185, 269,

377, 378, 460, 723, 910

Gough, M. W. , E-137, 296, 548,

724, 911, 984, 1057

Graf, Calvin R. , E-549

Grant, Arthur S.G., E-165, 250

Gray, Richard E. , E-350, 461, 828

Green, James W. , E-105

Grisdale, G.L. , E-725

Gronlund, M. , E-379

Grosskopf, J. , E-138, 380, 381,

912, 913

Grozier, A.L. , E-550

Grudinskaia, Galina Petrovna, E-726

Grun, Artur, E-74

Gubskii, V.F. , E-665

Gudmandsen, P. E. , E-297, 462, 743,

1058

Guiraud, F. O. , E-964

Gusiatinskii, A. I. , E-632, 829

Hachenberg, O. , E-633

Hakkarinen, W. , E-209

Halbert, H. W. , E-49

Hamilton, D.H. , Jr. , E-539

Hamlin, E. W. , E-59

Hansel, Christian, E-914

Harden, B. N. , E-259, 411

Harding, W.B. , E-1068

Hargreaves, J. K. , E-985

Hargreaves, S. , E-985

Harman, J.C. , E-253

Harrington, Edward L. , E-531

Harris, Donald B. , E-75

Harstad, H. , E-545

Hartman, William J. , E-634, 986

Hasegawa, Taro, E-420

Hathaway, S.D. , E-635

Hauer, A. , E-139

Hay, D.R., E-298, 299, 636, 637,

915, 916, 987, 1020

Hay, H.G. , E-140, 166

Hayre, H.S. , E-830

Head, Howard T. , E-727

Heer, O. , E-300

Heffner, R. W. , E-988

Heightman, D. W. , E-106

Heikkila, W.J. , E-451

Herath, Fritz, E-76

Herbstreit, J. W. , E-170, 199, 203,

272, 301, 638, 728, 850, 917,

1045, 1059

Hershberger, W. D. , E-546

Hessemer, R. A. , Jr. , E-831

Hickin, E. M. , E-729

Hines, CO. , E-141

Hirai, Masaichi, E-463, 551, 572,

730-732, 832, 833, 922, 989,990

Hirao, Kunio, E-167, 302, 382, 464,

552, 639, 778, 834

Hiser, H.W. , E-733

Hoffer, Thomas E. , E-531

Hoffman, J. D. , E-734

Hogarth, J.E. , E-451

Hogg, D.C., E-458, 620, 640, 918

Holden, D.B. , E-755

Holzworth, George C. , E-323

Hood, A. D. , E-204

Hooper, A.H. , E-383, 384

Hopfield, H.S. , E-991

Hopkins, H. G. , E-276

Hopkins, R.U.F. , E-385, 851, 852

Horn, J. D. , E-611, 613, 696, 697,

807, 808

Hornberg, K. O. , E-272, 1045

Howe, Herbert H. , E-432

Hubbard, R. W. , E-1060

Hund, August, E-168

Hund, Loyd E. , E-18

Iakovlev, O.I. , E-386

Ikeda, Masao, E-311

Ikegami, F. , E-735, 1061

litis, Jean, E-721

Inkster, W. J. , E-280

Inoue, Ryosuke, E-732, 922

Institute of Radio Engineers. Committee on Wave Propagation, E-205

Institute of Radio Engineers—International Scientific Radio Union,

Wash. ,D.C. , E-169

International Radio Consultative Committee, E-303

International Scientific Radio Union,

E-919

IRE-URSI Symposium, April 30-May 1-3,

Wash. , D. C. , and Oct. 11-12, 1956,

Berkeley, Calif. , E-465

Irgens, F. , E-1035

Irie, Hiromi, E-656, 776, 777, 904

Ishii, Takahiroo, E-524, 690

Ishizawa, Yoshihiro, E-922

Israel, Hans, E-77

Isted, G. A. , E-553, 554, 992

Iudin, O. I. , E-873
284

Jackson, CM. , E-1041

Jackson, H.B. , E-l

Jakes, W.C. , Jr. , E-160

Janes, H.B. , E-304, 305, 319, 677,

736, 780

Jansen, R. J. , E-1068

Japan. Radio Research Laboratories,

Tokyo, E-306

Japan. Science Council. Japanese

National Committee for the URSI,

E-993

Jarkowski, H. , E-83

Jasinski, W. , E-251

Jatlow, J.L. , E-545

Jehn, K.H. , E-206, 457, 641

Johansen, D. E. , E-867

Johler, J. R., E-466, 737, 835, 956

Johnson, CM. , E-519

Johnson, Mary Ellen, E-555, 565,

798, 881

Johnson, Walter E. , E-207

Joint Technical Advisory Committee,

E-1062, 1063

Jones, D.E. , E-387

Jones, D.S. , E-994

Jones, E.H. , E-142

Jones, F.E. , E-79

Jones, R.F. , E-78, 107, 307, 556

Jones, R.N. , E-253

Josephson, B. , E-557, 558

Jowett, J.K.S. , E-559

Joy, R.R. , E-1067

Joy, W. R.R., E-560, 561, 838

Kajikawa, Makoto, E-524, 690

Kalaba, Robert, E-701

Kalinin, A.I. , E-388, 642, 738,

739, 796, 836

Kalinin, Iu. K. , E-562, 563, 740

Kamen, Ira, E-389

Kandoian, Armig G. , E-350

Kane, Julius, E-1036

Kaner, E. A. , E-608, 643-645,

884, 891

Karapiperis, L. N. , E-874

Kariambas, N. K. , E-874

Karp, Samuel, E-108, 885, 1036

Karpeev, G. A. , E-669, 670

Kashprovskii, V. E. , E-995

Kato, Joji, E-905

Katz, Isadore, E-33, 356, 444, 1064

Katzin, M. , E-741

Kazansky, B. , E-252

Keary, T. J. , E-646

Kennaugh, E. M. , E-564

Kennedy, R.N. , E-816

Keitel, G.H. , E-223

Kerr, Donald E. , E-60, 143

Kerr, F. J. , E-61

Kido, Yoshihisa, E-732

Kiely, D.G. , E-208, 1065

Kinber, B. E. , E-742

Kirby, Roberts., E-170, 253, 308,

390, 391, 467, 799, 837, 965,

1066

Kirby, S.S., E-14

Kirke, H.L. , E-80

Kirkpatrick, A. W. , E-780

Kitchen, F. A. , E-276, 468, 565,

566, 838, 1067

Kleinsteuber, Werner, E-74

Klinger, Hans Herbert, E-62

Klinker, Ludwig, E-254, 309, 310,

392, 393, 469-471

Knighting, E. , E-109, 144

Knopfel, W. , E-472

Knudtzon, N.H. , E-743, 920

Koch, G.F. , E-744

Koch, J. W. , E-1068

Koenig, J. D. , E-746

Koido, H. , E-921

Kono, Tetsuo, E-311

Koo, B.Y.C, E-741

Koono, Tetsuo, E-922

Kopeck, R. , E-871

Koreicho, W. , E-713

Krasil'nikov, V. A. , E-81, 394, 923

Krauz, L.I. , E-594

Kreielsheimer, K.S., E-491

Krevsky, Seymour, E-1069

Krylov, G. N. , E-924

Kuhn, Udo, E-473, 474

Kulshrestha, S.M., E-925, 926

Kummer, W.H. , E-620, 647

Kuperov, L.P. , E-1070

Kurihara, Yoshitaka, E-312, 730

Kuzubov, F.A. , E-995

La Frenais, N. D. , E-722

La Grone, Alfred H. , E-171, 313, 648,

745, 839

Lane, J. A. , E-32, 840, 902, 968,

969, 996

Lange, Heinz, E-708

Langille, R.C , E-299

Larsen, B. F. , E-1058

Latorre, V.R. , E-927

Laurens, A. , E-746, 928

Lauter, Ernst A. , E-172, 254

Laver, F. J. M. , E-314

Lee, Chi-chen, E-997

Lehfeldt, Wilhelm, E-82
285

Lemoine, P. , E-747

Leonhard, J. , E-401

Leontovich, M. , E-34

Levatich, J.L. , E-953

Levine, D.J. , E-545

Levshin, LP. , E-666

Lewin, L. , E-1071

Lieberman, G. , E-908

Lilley, CM. , E-737, 835

Little, C.G. , E-1066

Lizuka, Keigo, E-998

Long, William G. , E-475

Longley, A. G. , E-667

Lotova, N. , E-748

Love, A.E.H. , E-ll

Lowell, P.D. , E-209

Lu, Pao-wei, E-649

Lucas, W.J. , E-523, 722, 826

Lucke, W.S., E-358

Lucy, R.E. , E-395

Lund, CO. , E-379

Luscombe, G. W. , E-491

MacCollum, Robert, E-841

MacDonald, F.C, E-581, 861

MacDonald, H. M. , E-2, 5, 9

Mack, CL. , Jr., E-315, 401

Mackey, CL. , E-749

Mackey, R.C , E-546

MacLean, K.G. , E-26

Maenhout, A. G. , E-396, 842, 843,

930, 999

Maheshwari, R.C, E-931

Maksimov, G.S. , E-864

Malaviya, V. , E-827

Malkowski, G. , E-567

Malnar, L. , E-706

Maloney, L.J. , E-271, 651, 837,

1044, 1055

Mansfield, W.V. , E-320

March, H. W. , E-8

Marconi, Guglielmo, E-16

Marriott, Robert H. , E-10

Marshall, J.S. , E-932

Mathews, F.S., E-1027

Martin, Edward J. , E-353, 486,

687, 1043

Martin, F.L. , E-1000

Martin, S.J. , E-751

Maruyama, Hiroyuki, E-302

Matsuo, Masaru, E-1001

Maxwell, E.L. , E-514, 1027, 1096

Mayer, James H. , E-525

Mc Craken, Leslie G., E-476

Mc Donald, D. J., E-650

Mc Gavin, R.E., E-355, 651, 929, 964

Mc Leish. CW. , E-750

Mc Petrie, J.S. , E-43, 44, 83, 1072

Mc Quate, P.L. , E-308, 391

Meadows, R.W. , E-844

Meany, Frances M. , E-236

Medhurst, R.G. , E-933

Megaw, E.C.S., E-45, 63, 110,

210, 477

Mellen, G.L. , E-316

Men", A. V., E-652-654, 845, 934,935

Merkulov, V.V. , E-478

Meyer, Hans Klaus, E-1002

Meyer, James H. , E-525

Millar, J.Z. , E-lll

Miller, G.A. , E-49

Miller, J. Z. , E-191

Millington, G. , E-27, 84, 479, 568,

655

Millman, George H. , E-397

Milnes, B. , E-112

Misenheimer, Harvey N. , E-398

Misme, P. , E-399, 541, 542, 569,

628, 752-754, 846, 847, 889,

901, 936, 1037, 1038

Moler, W.F. , E-400, 570, 755

Mondloch, A. , E-871

Moore, R.K. , E-830

Morris, D. , E-1003

Morrow, W. E. , Jr. , E-316, 401, 1004

Moyer, Vance E. , E-402, 480

Muchmore, R.B. , E-317, 344, 1005

Muller, K. , E-499

Mumford, W. W. , E-23, 24

Muramatsu, Kinya, E-270

Murphy, Anabeth, E-513, 1087

Naito, K. , E-211, 212, 937

Nakamura, Takuma, E-777

National Research Council, Wash. , D.C , U.S. National Committee on

the International Scientific Radio

Union, E-756

Naumov, A. P. , E-1031

Neal, G. A. , E-626

Nefedov, E.I. , E-1006

Nekrasov, L.B. , E-938

Nemirovskii, A.S., E-757, 848

Neumann, J. , E-173

Newman, P. , E-257

New Zealand. Dept. of Scientific and

Industrial Research, E-145

Nichols, B.E. , E-401

Nicholson, M. A. , E-6
286

Nishikori, Kiyoshi, E-311, 656

Niwa. Shuntaro, E-481, 572

Northover, Francis H. , E-174, 318,

849

Norton, K. A. , E-30, 50, 64, 170,

203, 213, 319-322, 403, 657-

659, 667, 758, 800, 850, 882,

939

Obukhov, A. M. , E-394, 660

Okamoto, Hironobu, E-571

Olivier, M. , E-759

Omberg, A. , E-50

Onoue, Michio, E-482, 572

Orimo, Jinsuke, E-589

Ortwein, N. R. , E-851, 852, 1073,

1074

Ose, Masami, E-571

Ostrovskii, I.E. , E-811

Overcash, Frank J. , E-146

Ozanich, A. M. , Jr. , E-696

Pappas, C.F. , E-853

Paraskevopoulos, P. , E-521

Parke, Nathan Grier, III, E-113

Parkinson, C.E. , E-1007

Parkinson, T. , E-14

Parry, C.A. , E-573, 760, 854,

1008, 1009

Patrick, W.S. , E-1010

Paynter, D. A. , E-725

Pedersen, Peder Oluf, E-12

Pellerin, J. , E-759

Pemberton, E.V. , E-915

Perlat, Andree, E-65, 85, 114, 214

Perers, Olaf F. , E-147

Peterson, C.F. , E-797

Peterson, Donald W. , E-201, 255, 370

Petrovskii, A. D. , E-761

Pezzner, H. , E-741

Pfister, Wolfgang, E-19

Phillips, W.Eric., E-115, 148

Phillpot, H.R. , E-483

Physical Society of London and Royal

Meteorological Society, E-51

Pickard, Greenleaf W. , E-52, 116

Pivarunas, Frank A. , E-1075

Plank, Vemon G. , E-369, 404, 484,661

Pluchard, A. G. , E-762

Plush, R.W. , E-720, 1096

Poeverlein, Hermann, E-323, 405, 406

Pohl, J.E. , E-851, 852

Pollack, L. , E-545

Ponomarenko, L. M. , E-662

Portmann, P. A. , E-283

Pospelov, L.A. , E-884

Pote, Alfred J. , E-287, 316

Potts, D.H. , E-407

Potts, J.B. , E-809

Priimak, G. I. , E-763

Prescott, Howard, E-1011

Pressey, B. G. , E-408

Price, W.L. , E-66

Prokott, Ernst, E-324

Prosin, A.V., E-574, 575, 663-666,

764-767, 855-858

Pryce, M.H.L. , E-48

Pucher, G. , E-945

Radford, W.H. , E-316

Radio Corporation of America. David

Sarnoff Research Center, E-46

Raghavan, S. , E-940

Rai, D.B. , E-859, 860

Rainey, R.J. ,Jr. , E-688, 1012

Rainville, L.P. , E-537, 619

Randall, D.L. , E-209, 256

Rawhauser, R. , E-773

Ray, P.R. , E-733

Reen, J.H. , E-215

Reid, W. M. , E-916

Remizov, L.T. , E-768

Rempel, R. W. , E-407

Rice, P.L., E-203, 216, 319, 322,

638, 667, 800, 837, 853, 882,

1076

Richards, E.G., E-566, 577, 838,

1067

Richmond, I.J. , E-468, 566

Riddle, R.L. , E-257

Rider, G.C., E-217, 578, 579,

941, 1013

Riggs, Lowell P. , E-580, 612,

613, 697

Ring, R.M. , E-282, 1014

Ringwalt, D.L., E-581, 861

Rivet, Pierre, E-409

Robbins, R.L. , E-218

Robinson, G. D. , E-942

Rocco, M.D. , E-86

Roche, J.F. , E-283, 537, 619

Rodak, M.I. , E-668

Roessler, E. , E-325

Roger, T. F. , E-267, 268, 326, 353,

486, 603, 687, 1043

Rogers, G.L. , E-485

Root, H.G. , E-537, 619

Rowden, R.A. , E-487, 582

Royal Meteorological Society, E-51

Rubinshtein, la. M. , E-769

Ruina, J.P. , E-1077
287

Runge, W. A. , E-790

Rydbeck, OlofE.H. , E-67

Ryerson, J.L. , E-680

Ryzko, Stanislaw, E-488

Ryzhov, Iu.A. , E-873, 943, 1015

Sacco, Luigi, E-327

Sadoun, B. , E-219

Saito, Hiromu, E-551

Sakurazawa, Akira, E-589

Salamonovich, A. E. , E-770

Samoilov, G.P., E-1078

Sanin, F.S. , E-811

Santomauro, Luigi, E-862

Sapporo District, Japan. Central

Meteorological Observatory,

E-489

Satow, P.G. , E-117

Satyanarayana, R. , E-679

Sawaji, Kazuaki, E-S75

Saxton, J. A., E-118, 149, 258, 259,

276, 328, 333, 410, 411, 490,

491, 771, 944, 1072, 1080

Schachenmeier, Richard, E-150, 220,

412, 633

Schaetti, N. , E-124

Schafer, G.E. , E-203

Schelleng, J.C. , E-17

Schensted, C.E. , E-413

Schikorski, W. , E-151

Schlesinger, S.P. , E-519

Schmelovsky, Karl Heinz, E-414, 583

Schulkin, M. , E-175

Schunemann, R. , E-492, 493, 584,

945

Selvidge, H. , E-31

Semenoy, A. A. , E-669, 670, 878

Senn, H.V. , E-585

Shabel'nikov, A.V., E-415

Shaft, Paul D. , E-863, 946

Sharp, C.E. , E-395

Sharpless, William M. , E-41, 1079

Shiro, Isao, E-639

Short, P. J. , E-320

Shur, A. A. , E-864

Sichak, William, E-350, 351, 947

Siegel, K. M. , E-718

Siforov, V.I. , E-671

Silberstein, Richard, E-1081

Silleni, Stelio, E-329

Silverman, Richard A. , E-260, 330, 416,

494

Simon, J.C. , E-331, 877

Sindler, Iu. B. , E-865

Siscinski, L. , E-83

Slobodeniuk, G. I. , E-666

Smith, Ernest K. , Jr. , E-221

Smith, Dillon E. , E-35

Smith, H. W. , E-120, 313

Smith-Rose, R.L. , E-68, 119, 332,

333, 866, 1016

Smyth, John B. , E-53, 86, 385, 586

Sofaer, E. , E-587

Soicher, H. , E-962

Sokolov, A.V. , E-505

Sollfrey, William, E-108

Sommerfield, A. , E-4

Sommermeyer, K. , E-77

Soundararajan, K. , E-940

Spencer, C. W. , E-176

Spetner, L. M. , E-357

Springer, P. , E-773

Spizzichino, A. , E-772, 901

Stack-Forsyth, E. F. , E-334

Staley, R.C. , E-206

Stanley, Glen M. , E-774

Staras, Harold, E-335, 417,495,672

Stark, J. W. , E-487, 582

Starkey, B. J. , E-418, 588

Stamecki, B. , E-83

Stein, S. , E-867

Stetson, Harlan T. , E-52, 116

Stiles, K.P. , E-673

Straiton, A. W. , E-69, 120, 198, 261,

264, 313, 419, 502, 711, 775,948

Strand, Kaj G. , E-222

Stranz, Dietrich, E-121

Strohbehn, J. W. , E-1026

Stroud, J.C. , E-736

Stjernberg, BoK.E. , E-147

Suda, K. , E-262

Suzuki, Michiya, E-420, 1082

Svien, A.J. , E-375

Svien, Arlon S. , E-674

Swanson, D. A. , E-49

Swarm, H. M. , E-223

Sweezy, W. B. , E-1017

Swingle, Donald M. , E-122, 224, 225

Symposium on electromagnetic wave

theory, Univ. of Michigan, June

20-25, 1955, E-421

Tagholm, L.F. , E-582

Takahashi, Kozo, E-496

Takahira, Akira, E-656, 776, 777

Tao, Kazuhiko, E-163, 167, 263, 336,

422, 497, 498, 589, 675, 778

Tatarskii, Valerian I. , E-423, 590,

676, 779, 923, 949, 950

Taumer, F. , E-499
288

Taylor, A. P. , E-384

Teachman, A.E. , E-539

Telford, M. , E-500

Texas Univ. Electrical Engineering

Research Lab. , E-337, 501,1083

Thayer, G. D. , E-614, 615, 694,

698, 822, 868, 970

Treloar, H. M. , E-36

Thompson, Leland E. , E-70

Thompson, M.C., E-301, 677, 780,

1060

Thompson, M. G. , E-982

Thompson, Owen, E-781

Thorn, D.C., E-1012

Tidd, W.H. , E-338

Tipton, CD. , E-264

Tiufiakin, L.S. , E-768

Tohsha, M. , E-339, 951

Tolbert, C.W. , E-261, 264, 419,

502, 775

Toman, Kurt, E-782

Tomlinson, H.T. , E-678

Tratas, Iu. G. , E-1018

Trecker, J. M. , E-816, 967

Tremblay, Real, E-877, 952

Trenev, N. G. , E-591, 592

Troitskii, V. N. , E-424-426, 683, 783

Trolese, L.G. , E-53, 340, 385, 593

Tsel'min, A.E. , E-594

Tsuchiya, Kiyoma, E-524, 690

Tsvetkov, A. N. , E-575

Tsydypov, Ch.Ts. , E-1019

Turner, H. E. , E-987, 1020

Turner, W. R. , E-588

Twersky, Victor, E-503

Ugai, Shigetaka, E-1084

Unwin, R.S., E-88, 112, 140, 166,228

U. S. Air Force. Third Air Weather

Group, Ent Air Force Base, Colorado

Springs, E-177

U.S. Army, E-226

U.S. Naval Research Laboratory,

E-869

U.S. Navy Electronics Laboratory,

E-227

U.S. Navy Weather Research Facility,

E-595, 784

U.S. Office of Naval Operations, E-341

U.S. Office of Scientific Research and

Development. National Defense

Research Committee, E-87

Uyesugi, Y. , E-163, 167

Vainshtein, L.A. , E-547

Vassy, Arlette, E-178 . Vassy, Etienne, E-178

Venkateswarlu, P. , E-679

Verbitskii, I.L. , E-966

Vergara, W.C. , E-953

Vetter, M.J. , E-982

Vickers, G.A. , E-1021

Villars, F. , E-265, 342

Voge, Jean, E-214, 229-231, 541,

542, 628, 785-787, 976

Vogelman, J. H. , E-680

Vogler, L.E. , E-320, 322, 853

Vogt, K. , E-381

Volland, H. , E-1085

Vollhardt, Dieter, E-898 von Handel, Paul, E-19 von Rautenfeld, Friedrich, E-576

Von Rosenberg, C.E. , E-198

Voss, P.L. , E-1074

Vvedenskii, B. N. , E-504, 505, 795,

796

Vysokovskii, D. M. , E-433, 506-508,

596, 597

Wade, H. D. , E-788

Waibel, E. , E-1022

Wait, James R. , E-266, 427-432,

509-513, 598, 954, 955, 1023-

1025, 1039-1042, 1086-1095

Walker, G.B. , E-948

Walters, L.C. , E-737, 956, 1025

Waterman, Alan T. , Jr. , E-343, 599,

600, 1026

Watt, A. D. , E-514, 1027, 1096

Waynick, A.H. , E-54

Weeks, Ray R. , E-475

Weintraub, Stanley, E-221, 232

Weisbrod, S. , E-681

Weisskopf, V.F. , E-265, 342

Wells, P.I. , E-305

Wensien, H. , E-151

Weston, V.H. , E-1028

Whale, H. A. , E-1029

Wheelon, A. D. , E-317, 344, 345,

434, 515, 516, 672, 682, 1005

Wickizer, G.S. , E-26, 55, 179, 199,

233

Wiesner, Jerome B. , E-316, 321, 517

Wiggins, M.J. , E-1010

Wilkerson, J. , E-634

Wilkerson, Robert E. , E-957

Wille, H. , E-518
289

Williams, C.E. , E-241, 368

Williamson, V.L., E-789

Willson, F.E. , E-790

Wilson, AlvinC, E-870

Wiltse, J.C. , E-519

Wolf, E. , E-871

Wolf, James M. , E-958

Wolin, Samuel, E-234

Wong, MingS. , E-1097

Wood, H.B. , E-1030

World Meteorological Organization,

E-435

Wright, F.E. , E-959, 1Q00

Yamada, Ryozo, E-346

Yeh, L.P. , E-601. 602

Yerg, Donald G. , E-123

Yoshida, Noriaki, E-311

Yoshino, Takeo, E-872

Zenneck, J. , E-3

Zhevankin, S.A. , E-683, 1031

Zinichev, V.A. , E-873

Zlotykamin, C. , E-791

Zverev, V. A. , E-624, 792

ANONYMOUS - 1098-1110
290

SUBJECT INDEX

Absorption, E-3, 10, 82, 87, 121, 356, 683,

769,827,888,972,976

by fog, E-871

byH^O, E-62, 264, 441, 518, 770, 775,

A 827,871,905,1031

by 2, E-62, 264, 441, 770, 775, 827, 871

by

3

, E-827

by N20, E-827

Air masses, E-55, 107, 187, 197, 239, 263,

281, 307, 400, 605, 610, 696,

755,916,972

Continental, E-843

Polar, E-206,612,673

Inductive capacitances, E-876

Maritime, E-581,843

Moist, E-115,206,374,581,915

Monsoon, E-58

Tropical, E-58, 206, 843

Unstable, E-843

Air pressure, E-l, 94, 114, 151, 155, 209,

212, 221, 222, 224, 291, 310,

383, 474, 525, 527, 550, 556,

611,682,696,807

Aircraft (See: TECHNIQUES AND

METHODS, p. xxx)

Attenuation, E-26, 43, 44, 87, 147, 201, 214,

237, 298, 366-368, 560, 561, 578,

594, 640, 727, 774, 775, 801, 888,

905, 954, 988, 1024, 1028, 1040

by duct layers, E-339, 546

by fog, E-621

by H2C E-214, 502, 640, 729

by 2

, E-506, 640, 729

by03

, E-214

Atlases, E-341,675

Atmospheric altitudes, E-153, 214, 1046

100 meters E-615

125 E-274

128 E-274

300 E-662, 916

*?500 E-327

500 E-155,469, 735

600 E-88

750 E-409

1000 E-703, 753, 862

1140 E-409

1500 E-862,916, 1032

2000 E-904

3000 E-151

8000 E-154

0-1

0.25

1-2

3

4

6

8.45

<= 10

18

0-20

1-20

20

0. 1-70

12

3

<= 15

32

50

100

=-100

150

200

8-220

300

350

400

600

900

0-1000

1000

1200

1000-2000

2000

2200

<3000

3000

3800

4000

4560

<5000

5000

4000-6000

6000

7000

30-7800

1000-8000

8000

9800

km

ft.

E-897

E-502

E-21

E-805, 808

E-502

E-58

E-662

E-175, 188

E-25

E-776

E-273, 322

E-846

E-694

E-101

E-101

E-101

E-261

E-101

E-40, 101, 159

E-40, 78, 127, 166

E-54, 55

E-40

E-40, 621

E-204

E-40

E-166

E-1017

E-334

E-1017

E-145

E-40

E-1017

E-145, 942

E -209, 861

E-307, 577

E-755

E-222,637,723

E-257

E-485, 869

E-189

E-131

E-550, 580, 948,

1017

E-581

E-861

E- 146, 838

E-203

E-24

E-383, 485

E-525
291

3000-10, 000 f t. E-223

10, 000 " E-79, 195,418

11,000 1 E-196

6220-14,110 1 E-355

20, 000 1 E-79, 195, 281, 285

25, 000 ' E-281

30, 000 • E-79

40, 000 E-142

60, 000 E-385,622

70, 000 E-1017

100, 000 E-522

130, 000 11 E-441

1000 millibars E-1084

900 " E-921, 951, 1084

950-900 II E-176

850 11 E-999

700 " E-176, 474

500 II E-400, 862

Atmospheric convective activity, E-374,

404

Atmospheric density, E-613

Atmospheric gases (see also humidity,

moisture, water vapor p. 279)

Argon, E-164

Nitrogen, E-164

Oxygen, E-164, 640

Water vapor, E-640

Absorption, E-62, 264, 441, 518,

770, 775, 827, 871, 905, 1031

Attenuation, E-214, 502, 640, 729

Pressure, E-10, 33, 52, 77, 84, 115,

123, 212, 249, 278, 309, 334,

422

Atmospheric inhomogeneities, E -344, 345,

470, 493, 506, 543, 544, 556,

661,670,682,1048

Atmospheric mirage, E-163

Atmospheric stability, E-846, 847

Atmospheric thermodynamic stability,

E-569

Atmospheric structure, E -345, 455, 902,

976

Atmospheric vertical structure, E- 1033, 1040

Atmospheric vertical motion, E-400, 469-

471,599

Auroras, E-20

Bibliographies (=- 50 refs. ), E-14, 46, 76,

87, 98, 129, 136, 168, 181, 192,

205, 255, 276, 277, 314, 322, 325,

337, 397, 404, 406, 436, 449, 452,

465, 501, 505, 595, 597, 605, 646,

658, 659, 676, 684, 710, 744, 769,

771, 796, 824, 841, 875, 880, 883,

886, 950, 972, 987, 993, 1031

1073, 1083, 1093

C - region, E-22, 23

Clouds

Cloud base heights, E-861

Cloud scattering, E-113

Cloud structure, E-438

Cumulus, E-374, 484, 531, 661

Stratocumuli, E-524

Thunderclouds, E-77,439

Collected works, E-126, 227, 421, 452, 919

Conductivity

-of different soils, E-1027

-of ice, E-1027

-of permafrost, E-1027

-of rocks, E-1027

-of snow, E-1027

Surface, E-34, 252, 262, 432, 440, 644,

645, 983, 995, 1025, 1027, 1085,

1095

Seasonal variations, E-977

Contrasts near coastlines, E-960

Sea conductivity, E-1025

Great Lakes, E-977

Cosmic rays, E-12

Curves,

Basic propagation loss, E-927

Calculating absorption for different

atmospheric layers, E-827

Calculating field strength, E-48, 140,

497,559, 728,977

Communication prediction, E-941

Communication system engineers,

E-456

Coupling loss/narrow beam antennas,

E-918

Ground wave propagation, E-303,432,

737, 1025

Polarization, E-84

Reflection, E-48

Refraction. E-175

Data publications, E-40, 60, 61, 70, 76, 118,

132, 145, 241, 322, 460, 680,

688, 696

Design considerations (see Pt. 4, p. xxviii)

Dew point, E-10, 40, 122, 153, 155, 222, 224

Dielectrics

Dielectric constant, E-77, 87, 94, 99,

100, 115, 134, 141, 238, 289,

415, 440, 507, 642, 644, 664,

738, 742, 761, 872, 954, 977.

983, 1048

Boundary conditions, E-691, 1036

Discontinuities, E-849

Distribution, E-318

Fluctuations, E-344, 434, 515, 516,

649, 755, 836,859, 1034, 1086

Irregularities, E-424,448, 494, 649,

712, 723
292

Survey, E-426

Loss, E-90,872

Magnetic field intensity, E-3,9,12

Noise, E-617,707

Plane layered dielectrics, E-1003

Spectrum, E-852

Transmitivity fluctuations, E-766

Wedges, E-108

Diffraction, E-6, 17, 19, 31, 42, 70, 86, 93,

108, 137, 138, 150, 201, 217, 219,

299, 304, 373, 406, 455, 459, 472,

485, 551, 560-562, 568, 691, 692,

709, 718, 726, 744, 795, 836, 838,

844, 848, 876, 885, 899, 956, 985,

994, 1006, 1055, 1057, 1090

Knife edge diffraction, E-201, 1046

Loss, E-96,328,551

Zones, E-248

Ducts, E-l, 3, 6, 39, 64, 65, 73, 78, 85, 93,

95, 99, 107, 109, 120, 127, 134,

140, 144, 145, 148, 163, 166, 173,

183-185, 195, 204, 208, 228, 261,

278, 334, 339, 365, 372, 385, 414,

446, 547, 581, 609, 621, 656, 708,

726, 741, 776, 806, 821, 860, 861,

869, 962, 979, 1024, 1061, 1067,

1074, 1097

Echoes

Amplitude, E-23, 423, 590, 643, 653, 654,

682, 699, 730, 737, 739, 779, 826,

844, 884, 922, 923, 934, 943, 945,

949, 952, 956, 973, 975, 998, 1023,

1025,1048, 1050

Gaussian, E-743

Angle of arrival, E-41, 69, 87, 99, 160,

317,344, 538, 894, 1026,1079,1097

From cloudless sky (radar angels),

E-178, 404, 457, 528, 556, 605,

606, 823, 916, 938, 958, 1032

From horizontally stratified atmosphere,

E-189, 1080

New type, E-571

Phase, E-423, 590, 643, 652-654, 677,

582, 699, 737, 779, 845, 864, 884,

923, 934, 939, 943, 949, 956, 973,

975, 998, 1003, 1023, 1025

Short range echoes, E-834

Eddies, E-149, 330, 531, 915, 916, 937

Effects on radio communication (See:

RADIO COMMUNICATION,

p. xxiii)

Fading, E-81, 91, 111, 147, 179, 191, 215,

229, 235, 237, 261, 286, 294, 297,

298, 302, 308, 314, 338, 366, 393,

426, 462, 469, 481, 494, 518, 524,

Fading (cont'd.

539, 557, 559, 579, 581, 620, 626,

627, 656, 666, 670, 682, 755, 769,

783, 826, 856, 874, 907, 912, 920,

952, 1046,] 049,1051,1058,1097

Doppler shift, E-1026

Duration, E-720, 722, 743, 913

Fadeouts, E-237,881

Fading rate, E-39, 340, 382, 494, 523,

579, 601, 625, 637, 670, 690,

722, 751, 844, 861, 913, 1026,1075

Fading regions, E-821,992

Mechanism, E-23, 382, 420, 643,1061,1065

Rapid fading, E-669, 699, 738

Selective fading, E-730, 863, 894, 988

Short term fading, E-965

Slow fading, E-738, 742, 865

Field strength, E-13-15, 19, 26, 30, 38, 43,

48, 55, 70, 81, 91, 93, 105, 111,

132, 142, 147, 149, 166, 179, 185,

187, 191, 201, 206, 208, 213, 223,

228, 230, 248, 258, 261, 262, 282,

296, 297, 299, 307, 309, 310, 313,

314, 318, 327, 328, 347, 355, 392,

418, 422, 426, 432, 434, 594, 597,

603,60 ,610.675,678,700,725-

727, 732, 736, 764, 769, 772, 774,

786, 796, 799, 805, 809, 832, 843.

847, 856, 857, 861, 874, 877, 878,

907, 912-914, 921, 928, 945, 960,

969, 983, 984, 992, 1007, 1015,

1018, 1026

Annual variation, E-473

Beyond horizon, E-16, 17, 19, 37, 39, 48,

81, 133, 149, 216, 219, 237, 254,

263, 271, 279, 282, 301, 316, 322,

325, 326, 345, 367, 386, 406, 453,

468, 477, 493, 558, 559, 570, 577,

582, 588, 597, 599, 600, 605, 618,

620, 666, 682, 690, 716, 717, 732,

755, 843, 847, 962

Curves, E-48, 140, 497, 559, 728, 977

(See also under TECHNIQUES

AND METHODS, p. xxx-xxxiv)

Daily variation, E-309, 473, 474, 497,

548, 690, 724, 735

Diffused field, E-772

Field intensity measurements, E-151,

132, 163, 172, 184, 266, 267, 270

Ground waves, E-80, 258, 259, 679,

702, 820

Statistical evaluation, E-576,878,

952

Within optical range, E-317,322,

373, 682

Hourly variation, E-336

Rayleigh Distribution, E-320, 445, 521,

539, 584, 601, 626, 630, 643, 651,

699, 718, 743, 844, 945, 973, 1030
293

Reflected field, E- 772, 878

Scatter fields, E-345, 356, 358, 463

Seasonal variation, E -497, 690, 743

Fog, E-398,454,940

Absorption, E-871

Attenuation, E-621

"Foliation", E-1037

Formulas

Batchelor's/scatter cross section, E-577

Booker and Gordon's formula, E-171,

216,275

Bremmer's formula, E-432

Brogg's statistical formula, E-950

Debye's expression/refractive index,

E-886

Domb and Pryce's formula, E-43

Einstein - Focker's formula, E-538

Fresnel's formula, E-656

Fresnel - Kirchoff's formula, E-985

Gordon's/spherical Earth, E-312

Green's functions, E-246,446

Hankel's functions, E-956

Hufford's formula, E-534

Kirchhoff's approximation, E-373, 520

Laplace's differential operations, E-346

Leontovich and Fok's formula, E-662

Maxwell's formula, E-134, 543, 950, 980

Norton's prediction formula/a new regression coefficient, E-941

Pekeris, Booker and Gordon's integral

expressions, E-417

Poisson's formulas, E-346

Riccati's differential equation/solution,

E-956

Sommerfield's formula, E-238

Van der Pol's formula, E-432

Van der Pol and Bremmer's formulas,

E-981

Watson's formula/diffraction, E-373

Watson's formula/transformation, E-446

Whittacker's functions, E-446

Wong's equations/ray curvature, E-1000

Absorption, E-683

Angle diversity correlation, E-922

Angle of scattering, E-748

Antenna gain loss, E-766,922

Atmospheric structure, E-942

Attenuation coefficient, E-42

Attenuation function, E-562, 563, 594

Bandwidth estimation, E-1009

Conductivities, E-975

Correlation functions/amplitude-frequency

-multipath distortions, E-730

Correlation functions/phase and amplitude, E-652,654,943

Correlation functions/transhorizon system design, E-665

Cross noise power, E-767

Cross talk calculation, E-663

Dielectric constants, E-975

Diffraction, E-48, 138

Diffraction prediction, E-994

Diffraction/surface waves, E-591,

592

Directional transmission, E-3

Eddy diffusion, E-776

Effective scattering volume, E-1043

Eigenvalues, E-318, 662

Field strength, E-48, 166, 309, 344, 405,

434,459,836,981

Ground wave field strength, E-30

Ground wave/property definition, E-440

Height gain differential equation/solution, E-892

Intermodulation noise, E -863, 947

Light shadow zones, E-42

Maximum range of radars, E-50

Narrow beam bandwidth, E-275

Nonspherical Earth, E-312

Percent of tune/non-interference of

signals, E-658

Radio refractive index, E-164, 177,

595, 975

Radio refractive index, analog computer solution, E-207

Radio wave propagation, E-53, 629,

731,773

Radio wave refraction, E-155,868,

976, 1012

Radio wave refraction, prediction,

E-970, 994

Relative beam curvature, E-128

Scattering of radio waves, E-496, 506-

508

Signal strength/antenna characteristics,

E-1015

Signal strength/diversity effects, E-832

Signal strength/fluctuation prediction,

E-38

Surface wave problem solution, E-34

System design, E-851,854

System loss, E-658

System performance, E-854

TV band (300-900 Mc/s), E-162

TV distortion/estimation, E-829

3 - D ray paths, E-1000

Transmission loss, E-403

Tropospheric influence/Doppler shift/

satellite signals, E-991

USW propagation, E-18

Volume, E-171

Wave phase, E-67

Waves, E-282
294

Frequencies (bands), (See: WAVE CHARACTERISTICS, p. xvi-xix)

Frequency bandwidth, E-295, 738, 852, 890,

967

Bandwidth capabilities, E-295, 338, 424,

462, 468, 490, 682, 731, 816, 848,

857,863,946, 1009

Frequency correlation of radio waves, E-891

Frequency correlation of signal scintillation, E-1005

Frequency dependency, E-758, 815, 829,

884,990

Frequency fluctuations, E-939, 967

Sweep frequency studies, E-647

Voice frequency, E-1030

Fronts, E-52, 55, 65, 167, 310, 377

Arctic fronts, E-637

Coastal fronts, E-249

Cold fronts, E-22, 40, 108, 612, 641, 921

Polar fronts, E-612,637

Structure, E-942

Warm fronts, E-40, 610, 921

General reviews and surveys, E-33,45,68,

87, 106, 121, 130, 145, 160, 180,

240, 241, 276, 279, 285, 314, 325,

329, 359, 380, 394, 395, 407, 410,

435, 437, 480, 504, 536, 555, 582,

589, 618, 624, 638, 646, 659, 824,

899,920,929,944,1061

British works, E-944

Japanese works, E-993

Soviet bloc works, E-883

U.S. works since 1957, E-895

Scattering theories, E-920

Theories/index of refraction, absorption

and dispersion, E-972

Theories of radio wave propagation in

terrestrial waveguides, E-1024

Graphical methods (See: TECHNIQUES AND

METHODS, p. xxxi)

Gravitational stratification, E-953

History, E-181, 671, 893

Humidity, moisture, water vapor, E-10, 36,

40, 56, 60, 73, 74, 78, 93, 102, 104,

126, 128, 153, 154, 159, 177, 180,

189, 209, 221, 250, 265, 284, 291,

329, 334, 347, 365, 374, 400, 404,

525, 527, 530, 542, 550, 609, 611-

613, 637, 696, 703, 723, 770, 806,

846, 862, 871, 916, 921, 940, 942,

987, 1020, 1037, 1074

Dew point, E-10, 40, 122, 153, 155, 222,

224

Fog, E-398,454,940

Mist, E-940

Influences on radio communication (See:

Effects on radio communication,

p. xxiii)

Instruments, (See p. xxvii - xxx)

Inversions, E-22, 28, 40, 56, 66, 76, 77, 112,

114, 123, 127, 152, 154, 173, 174,

176, 177, 189, 220, 307, 309, 310,

321, 360, 385, 422, 469, 470, 474,

487, 489, 546, 547, 581, 609, 741,

823, 849, 926, 942, 1074

Detection, E-179

Ionosphere, E-544, 687, 769, 1024

Upper air conditions, E-284,469

Ionization, E-12, 77, 82, 453

Auroral displays, E-20

Electron density, E-896

Free electron lifetime, E-12

Scattering, E-448,468

Meteor scattering, E-488, 646,

708, 726, 1043

Layers

Ground layers, E-660, 770, 780, 785-

787, 1002, 1046

Influence on geodetic measurements, E-780

Influence on radio navigation,E-780

Inversion layers, E-41, 229, 489, 525.

546, 566, 724, 849, 904, 921,1002

Lower layers, E-72, 74, 93, 116, 862,

934,938,951,1041

Influence on field strength, E-151,

400

Moving layers, E-1035

Reflective layers, E-909, 910, 922

Small layers, E-969

Stable layers, E-542, 846, 900, 936

Superrefractive layers, E-1046

Turbulent layers, E-542, 852

Undulated layers, E-937, 1026

Lectures, E-16, 139, 210, 933

Losses

Antenna beam deflection, E-922

Antenna gain loss, E-596, 738, 765,

766, 796

Antenna-to-medium coupling loss,

E-625, 680, 700, 722, 833, 852,

916, 918, 998, 1008

Dielectric loss, E-90, 872

Evaluation of losses, E-714

Frequency loss, E-916

Path losses, E-218, 486, 523, 525, 551,

572, 603, 616, 636, 687, 703, 709,

714, 720, 727, 736, 789, 797, 800,

338, 843, 894, 897

System loss, E-658, 719, 760
295

Transmission losses, E-190, 199, 203,

213, 218, 236, 272, 273, 286, 305,

308, 311, 322, 340, 353, 390, 391,

403, 441, 450, 462, 472, 486, 495,

523, 525, 569, 572, 577, 600, 603,

616, 625, 636, 658, 659, 667, 686,

687, 703, 709, 714, 720, 722, 721,

731, 736, 738, 758, 760, 765, 766,

789, 796, 797, 799, 800, 805, 828,

833, 843, 852, 887, 894, 897, 916,

918,922,998,990

Manuals, E- 195, 226

Maps

Air-sea refractive index difference,

E-460

Annual temperature, E-341

Ground conductivity/U. S. ,E-245,252,

977

Humidity, E-341

USA, Average absolute humidity,

E-442

World wide, E-441

Inversion frequency, E-194, 341

Probable service coverage of radio sta- tions, E-1021

Refractive index, E-341, 808, 840

World wide (sea level values),

E-611,696

mb, E-176, 400, 474, 862, 921, 951, 999

Meteor scattering, E-646, 708, 726,

Methods, (See: TECHNIQUES AND

METHODS, p. xxx-xxxiv)

Models (q. v. p. viii)

Monographs, E-12, 42, 67, 76, 147, 165, 173,

222, 240, 281, 293, 297, 310, 389,

405, 406, 418, 432, 483, 536, 583,

699, 821, 822, 824, 875, 895, 909,

912, 917, 923, 932, 936, 942, 944,

1059

Nitrogen (N^O) absorption, E-827

Nomenclature, E-221, 348, 526

Nomograms, E-263,456

Refractive index, E-79, 122, 123, 196

Oxygen (02) absorption, E-62, 264, 441,

770, 775, 827, 871

Oxygen attenuation, E-506, 640, 729

Ozone (OJ absorption, E-827

Ozone attenuation, E-214

Polarization, E-397, 411, 456, 543, 579,

720, 738, 744, 774, 884, 896,

973,988

Horizontal, E-23, 32, 43, 48, 84, 86,

519,659,702,844,984

Vertical, E-23, 32, 48, 84, 192, 519,

RQR. 653. 7^2 R3P 984

Propagation modes, E-188, 785, 786, 1085

Duct propagation, E-36, 67, 73, 200,741

Ground wave propagation, E-258, 428-

432, 450, 499, 509-513, 534, 563

591, 592, 655, 679, 702, 737, 740

880, 885, 906, 907, 955, 988, 995

1003, 1023, 1025, 1039, 1086-

1095

Ionospheric propagation, E-314, 319,

321, 332, 345, 649, 901, 1075,

1098, 1100

Reciprocal propagation, E-685

Scatter propagation, E-321, 345, 380,

403, 410, 426, 488, 490, 555, 571

623 (See also: Scattering)

Studies, E-75, 182, 183, 192, 201, 204,

206, 320, 321, 360, 367, 368,371,

375, 380, 394, 420, 423, 425,429.

432, 441, 443, 450, 457, 466,470.

477, 488, 490, 492, 509, 543,553,

554, 557, 562, 563, 591, 592,616-

618, 627-629, 649, 714, 741, 785,

786, 944, 949, 966, 967, 975,

1003, 1005, 1019, 1024, 1026,

1029, 1065, 1075

Mechanism, E-296, 426, 469-471, 492,

505, 515, 519, 546, 553, 555,

565, 567, 584, 588, 618, 620,

623, 625, 630, 649, 656, 708,

714-716, 726, 741, 755, 760,

785, 786, 796, 866, 880, 911,

937, 952

Velocity, E-3, 79, 291

(See also: RADIO COMMUNICATION, p. xxii-xxvii)

Radio communication

Effects on radio communication

(q. v. p. xxiii-xxiv)

Forecasting conditions for radio communication, E-35, 37, 38, 106,

163, 183, 269, 296, 308, 312, 322,

368, 443, 477, 480, 667, 712, 718,

719, 773, 797, 800, 882, 890, 931,

941,995,1009

From detractive index surface values,

E-803, 809, 819, 879, 970

From meteorological conditions,

E-580, 595, 615, 755, 805, 819,

874,877.940

Prediction curves, E-941

Radar transmission. E-339. 385
296

Paths

Path lengths (See p. xxv-xxvii)

Radar methods (See p. xxxii)

Radio methods (See p. xxxii)

Radio station aerial coverage probabilities, E-381, 837, 992, 1021

Telegraphy, E-714, 1030

Teletype aerial coverage E-619,686,

818, 1030

TV station aerial coverage, E-648, 731,

745,818,837,992

Prediction method, E-370, 648, 745

Survey technique for TV and radio

ranges, E-467, 922

Voice communication, E-619,627,

1030

Telephone, E-650, 709, 714, 818,

1021

Reflection, E-l, 6, 10, 17, 20, 22, 28, 54, 66,

72, 77, 82, 83, 87, 95, 132, 133,

188, 225, 318, 393, 406, 455, 469,

471, 476, 484, 583, 605, 678, 754,

769, 847, 910, 916, 967, 1057

Boundaries, E-24, 25, 53, 72, 206, 220,

393, 425, 445, 458, 541, 755, 901

Coefficients, E-801, 1082

Double reflection, E-13

From clear air strata (angels), E-1032

From coastlines, E-1023

From ground, E-45, 137, 138, 201, 844,

911

From ice, E-118

From rough sea surfaces, E-532,834,

973 1052

From rough terrain, E-445, 503, 651^ 1019,

1082

From sand, E-57

From snow, E-118

From tropospheric inhomogeneities,

E-425, 642, 726

From tropospheric layers, E-149, 708,

777, 785, 786, 922, 990, 1026,

1040, 1041

From water, E-45, 357, 444

Partial reflection, E-715, 755, 772, 785,

786,900,945,952

Specular reflection, E-901

Refraction, E-7, 10, 17, 19, 26, 35, 39, 47, 52,

55, 65, 72, 82, 86, 115-117, 126-

128, 137, 149, 150, 154, 155, 165,

172, 175, 179, 201, 221-223, 300,

301, 309, 310, 321, 339, 396, 415,

423, 433, 443, 457, 483, 493, 502,

508, 531, 593, 604, 633, 653, 657,

677, 681, 688, 693-698, 708, 726,

742, 769, 803, 811, 819, 822, 834,

853, 868, 879, 886, 887, 903, 907,

915, 921, 936, 961, 970, 991, 994,

997, 1006, 1040, 1041, 1057,1059

Molecular refractivity, E-807

Prediction, E-615

Water drop refractivity

Subrefraction, E- 1041, 1045 , 1099

Superrefraction, E-36, 39, 41, 56, 61, 73,

93, 95, 103, 109, 117, 126, 156,

178, 188, 194, 208, 237, 240, 249,

282, 284, 327, 339, 365, 372, 385,

425, 437, 438, 454, 539, 541, 567,

806,860,925,940

Nocturnal, E-135

Prediction, E-365

Refractive index (See p. ix-x and p. xxxiii)

Research programs, 1043, 1066, 1107

Cheyenne Mountain Propagation Program,

E-237,271,272

Japan's Antarctic Research Expedition,

E-571

Research reports

Committee reports, E-49, 51, 87, 124,

303, 586, 648, 728, 756,1062,1063

Project reports

The "Arowa" project, E-595

The Canterbury project, E- 145, 228

Scientific reports, E-33, 35, 36, 67, 87,

101, 108, 129-132, 145, 200, 255,

261, 264, 369, 385, 437, 480, 501,

595, 641, 788, 813, 823, 851, 869,

888, 987, 998, 1014, 1073

Technical reports, E-34, 93, 99, 113, 122,

140, 146, 151, 152, 157, 177, 194,

195, 197, 215, 269, 272, 298, 337,

343, 360, 397, 418, 531, 580, 622,

638, 659, 667, 737, 789, 798, 800,

819, 821, 822, 835, 837, 879, 882,

929, 963, 964 , 1054, 1075, 1083,

1093

Scattering, E-82, 87, 110, 135, 149, 183, 188,

210, 219, 254, 265, 283, 295, 309,

310, 317, 318, 321, 331, 332, 335,

342-344, 363, 382, 406, 416, 417,

448, 455, 462, 468, 496, 498, 500,

508, 520, 529, 532, 549, 557, 561,

578, 584, 589, 594, 596, 599, 600,

605, 607, 632, 637, 643, 649, 660,

662, 671, 674, 680, 700, 707, 712,

749, 754, 755, 758, 764-766, 769,

779, 788, 792, 794, 797, 810, 818,

836, 844, 848, 851, 852, 859, 864,

873, 898, 912, 913, 923, 927, 937,

944, 997, 1028, 1034, 1049

Angles, E-507, 508, 538, 634, 748, 852,

873, 1035

Coefficients, E-927

Cross section, E-1034

Distribution of scatterers, E-533, 639
297

Doppler shifting, E-494

From auroras, E-20

From "chaffs", E-831

From drifting scatter centers, E-844

From inhomogeneities, E-425, 642, 668,

682, 726, 792, 834, 836, 949, 950

From ionized regions, E-453,493

From meteors, E-488, 646, 708, 726, 1043

From moving layers, E-1035

From refractive absorbers, E-1028

From rough land surfaces, E-352, 503,

628, 793

From rough sea surfaces, E-519, 532,

587, 834, 995 * From sinusoidal surfaces, E-520

From terrain, E-830, 859, 995

From trochoidal surfaces, E-520

From wavy layers, E-937

Mechanisms, E-362, 494, 496, 506, 519,

852, 950

Theories (See p. vi)

Review, E-920

Scintillation, E-120, 210, 317, 344, 423, 502,

524, 682

Frequency correlation, E-1005

Solar activities, E-10, 12, 25, 397, 544, 890

Statistical data, E-82, 131, 162, 167, 198,

241, 260, 289, 297, 331, 379

Storms, E-l, 29, 215,612

Monsoon storms, E-438

Rainstorms, E-317, 344, 932, 977, 1004

Snowstorms, E-10, 398

Thunderstorms, E-10, 298, 438, 514, 567,

925. 978

Stratification, E-21, 22, 52, 93, 105, 134,172,

189, 263, 318, 339, 346, 347, 377,

385, 400, 493, 542, 554, 580, 584,

588, 604, 637, 703, 704, 714, 735,

753, 755, 771, 777, 779, 788, 811,

823, 827, 842, 877, 900, 901, 936,

942, 945, 979, 996, 1040, 1041,

1047, 1080

"Foliation", E-1037

Gravitational stratification, E-953

Thermal stratification, E-823

Water vapor stratification, E-823

Surveys (See: General reviews and sur- veys)

Symposia, Conferences, E-169, 193,

227, 306,407,421,452,465,

526, 570, 646, 728, 875, 919,

1038, 1043, 1066, 1098, 1102

Techniques and methods, theoretical and

applied (See p. xxx-xxxiv)

Temperature, E-10, 33, 36, 40, 56, 60, 73, 74,

76, 81, 89, 94, 101, 104, 115, 122,

123, 126, 128, 151, 153, 155, 159,

177. 180, 183, 187, 196, 209, 212,

214, 221, 222, 249, 252, 263, 278,

284, 291, 309, 329, 334, 360, 365,

377, 400, 404, 416, 422, 448, 474,

483, 489, 525, 527, 542, 556, 569,

609, 611, 613, 696, 723, 806, 807,

862, 871, 940, 987, 1020, 1037 1074

Textbooks, E-71, 143, 161, 168, 181, 436,

449, 575, 597, 676, 687, 693, 699,

710, 769, 784, 880, 1095

Theories (See p. iv-vi)

Theses, E-242

Compilations, E-98, 337, 501, 1083

Transmission experiments, E-7, 10, 29, 45, 53,

70, 75, 87, 110, 112, 114-116, 142,

147, 183, 201, 203, 204, 206, 217,

247, 257, 271, 272, 280, 283, 286,

288, 311, 312, 315, 319, 324, 338,

345, 350, 367, 390, 398, 411, 461,

530, 537, 565, 566, 620, 674, 688,

731, 815, 816, 831, 837, 846, 847,

921,952

Beam swinging, E-599, 619, 647, 692, 732,

852,922,937,990

Digital information, E-817

Facsimile information, E-817

FM radio links, E-575, 663, 739, 829,

848, 932

Intermittent teletype VHF transmission,

E-686

Multichannel, E-4, 316, 338, 350, 475,

663, 689

Telephony, E-575, 663, 673, 932

Radio telephone tests, E-364, 410,486,

490, 545, 627, 650, 673

Simultaneous recording, E-26, 111, 280,

390, 616

TV, E-333, 338, 410, 467, 468, 490, 500,

545, 549, 582, 648, 727, 829, 928,

932,978,1007

Interurban TV, E-575

Two-path transmissions, E-858

Laboratory experiments, E-60, 316, 987,

1030

Turbulence, E-93, 101, 110, 127, 135. 206, 211,

240, 257, 282, 301, 309, 310, 318,

322, 335, 343, 345, 394, 463, 470,

492, 495, 506, 516, 529, 531, 542,

565, 588, 590, 594, 597, 649, 657,

664, 676, 704, 766, 771, 719, 785,

786, 852, 915, 923, 934-937, 939,

942, 943, 952, 968, 1002, 1049

Eddies, E-149, 330, 531, 916, 937

Microstructure, E-377, 660
298

Wave types

Alfven's hydromagnetic waves, E-67

Creeping waves, E-1028

Gravity waves, E-377, 1032

Ground waves, E-4, 30, 80, 226, 252,

258, 266, 303, 319, 408, 429,

510, 511, 631, 655, 659, 667,

1081, 1086-1095

Ground wave atlases, E-203

Ground wave field strength, E-80, 270

Ground wave surveys, E-259

Internal tropospheric waves, E-910

Light waves, E-230

LF waves, E-408, 509, 513

Ocean waves, E-444

Polarized waves, E- 598, 659, 839, 844

Sonic waves, E-890

Surface waves E, E-591

Surface waves H, E-591

Surface waves, Norton's, E-466

Surface waves, Sommerfield's, E-407

Tidal waves, E-890

VLF waves, E-1024

Wavelengths, E- 12, 738, 796

mm A, E-62, 214, 877, 1037

2. 5 mm E-62

3. 35 " E-502

4.3 " E-261,264, 502

6 " E-62

8 " E-770

8. 6 " E-261 , 419, 502, 905

Cm A, E-19, 73, 83, 214, 406, 783, 961,

962, 278

1-42 Cm E-57

60 E-361

75 E-870

86 E-823

1 Cim E-128, 147

1.25 ii E-41,160

1.5 ii E-122

>1.5 I E-224

3

ii E-45,59,73,83,93, 147,

183,204,228,454,567,

838,860,925,940

> 3

•i E-57

3.1 ii E-lll

3.2 ii E-59, 120, 261, 297, 340,

544, 560, 932

4.7 ii E-585

6

ii E-300

6-10 ii E-932

6.4 i E-297

9.3 I E-340

9

ii E-45, 82, 83, 183

9.2 " E-44

9.2 cm-1] . 5 m, E-43

10 m-10 cm, E-43

10.7 Cm E-585

16.2 ii E-lll

17 " E-297

23 ii E-93

24 ii E-340

25 " E-345

dm A, E-19, 47, 76,150,278,783,406,

525, 633

1. 07 dm E-585

1.62 " E-lll

1.7 " E-297

2. 3

" E-93

2. 4

" E-340

2. 5

" E-345

6. " E-361, 228

7. 5

" E-870

8. 6

" E-823

M A, E-19, 149, 150,278,406,470,471,

491, 525, 565, 566, 594

1. 36 m E-687

1.4 " E-326

1. 6-5 " E-23

2 " E-85, 114

3 " E-152, 206, 310, 392, 396

3. 5 " E-45

3. 4

" E-176, 843

3. 75 " E-548

5 m-2 cm E-842

7.

" E-72

10 " E-128

< 10 " E-56,85,325,406

10 m-10 cm E-43

14 m E-15

50 " E-15

125 " E-485

Wavelength dependence on distance,

E-617, 738

Winds, E-36, 55, 78, 102, 183, 256, 257, 278,

365, 404, 469, 524, 625, 755, 877,

925,940,1034

Air flows, E-339, 1037

Anticyclones, E-28, 487, 546, 560

Anticyclonic conditions, E-1007

Anticyclonic regions, E-860

Cirocco, E-l

Cyclones, E-l, 28, 377, 438

Gales, E-l

Trade winds, E-869

Tsunamis, E-377

Wind velocities, E-340, 973, 1034
299

LIST OF JOURNALS

Academie des Sciences, Paris, Comptes Rendus

Acta Electronica, Paris

Acta Meteorologica Sinica, Peking

Acta Technica, Budapest

Acta Technica, Prague

Advances in Electronics, New York

Akademie der Wissenschaften, Berlin, Wissenschaftliche Annalen

Akademiia Nauk SSSR, Moscow, Doklady

Akademiia Nauk SSSR, Institut Fiziki Atmosfery, Moscow, Trudy

Akademiia Nauk SSSR, Institut Zemnogo Magnetizma, Ionosfery i Rasprostraneniia

Radiovoln, Moscow, Trudy

Akademiia Nauk SSSR, Izvestiia, Ser. Fizika

Akademiia Nauk SSSR, Izvestiia, Ser. Geogr. i Geoiiz.

Alta Frequenza, Milan

American Geophysical Union, Washington, D.C. , Transactions

American Meteorological Society, Boston, Bulletin

Annalen der Meteorologie, Offenbach a. M.

Annalen der Physik, Leipzig, Ser. 4

Annales de Radioelectricite, Paris

Annales des Telecommunications, Paris

Annali di Geofisica, Rome

Archiv der Elektrischen Ubertragung, Wiesbaden

Australian Journal of Scientific Research, Melbourne

BRF, Technische Mitteilungen

Beitrtge zur Physik der Atmospha're, Frankfurt a. M.

Belgium. Vlaamse Academie voor Wetenschappen, Letteren en Schdhe Kunsten van, Beige. , Klasse der Wetenschappen, Mededelingen

Bell System, N. Y. , Technical Journal

British Communication and Electronics, London

British Institution of Radio Engineers, London, Journal

Canadian Journal of Physics, Ottawa

Ceskolovenska Akademie Ved, Prague, Acta Technica

Chalmers Tekniska Ho'gskolas, Gothenburg, Handlingar

Ciel et Terre, Brussels

Communication and Electronics, New York

Current Science, Bangalore

Deutsche Hydrographische Zeitschrift, Hamburg

Deutscher Wetterdienst in der U.S. Zone, Berichte

Discovery, London
300

Electrical Communication, New York

Electronic Technology (Formerly: Wireless Engineer), London

Electronics, New York

Electrotechnick, The Hague

Elektron, Munich

Elektronische Rundschau, Berlin

Elektrosviaz* Moscow

Engineering Journal, Montreal

FTZ. Fernmeldetechnische Zeitschrift, Brunswick

G.E.C. , Journal of Science and Technology, London

Geofisica Pura e Applicata, Milan

Geomagnetizm i Aeronomiia, Moscow

Germany (Democratic Republic). Meteorologischer u. Hydrologischer Dienst,

Abhandlungen

Great Britain. Telecommunications Research Establishment, Technical Note

Hemel en Dampkring, The Hague

Hochfrequenztechnik und Elektroakustik, Leipzig

Hochschule ftfr Elektrotechnik, Ilmenau, Wissenschaftliche Zeitschrift

Idojaras, Budapest

Indian Journal of Meteorology and Geophysics, Delhi

Ingenio'rvidenskabelige Skrifter, Copenhagen, Ser. A

Institute of Electrical and Electronics Engineers (Formerly: Institute of Radio

Engineers), New York, Convention Records

Institute of Electrical and Electronics Engineers (Formerly: Institute of Radio

Engineers), New York, Proceedings

Institute of Electrical and Electronics Engineers (Formerly: Institute of Radio

Engineers), New York, Transactions

Institution of Electrical Engineers, London, Journal

Institution of Electrical Engineers, London, Proceedings

Institution of Radio Engineers, Sydney, Proceedings

Institution of Telecommunication Engineers, New Delhi, Journal

Israel Meteorological Service, Meteorological Notes, Ser. A

Japan. Antarctic Record, Tokyo

Japan. Journal of Meteorological Research, Tokyo

Japan. Radio Research Laboratories, Tokyo, Journal

Japan. Radio Research Laboratories, Tokyo, Quarterly Review

Japan. Radio Research Laboratories, Tokyo, Review

Japanese Journal of Geophysics, Tokyo

Journal of Applied Physics, New York

Journal of Atmospheric and Terrestrial Physics, London

Journal of Geomagnetism and Geoelectricity, Tokyo

Journal of Geophysical Research, Washington, D.C.

Journal Scientifique de la M4teorologie, Paris

Journal of the Aero/Space Sciences. New York (Formerly: Journal of the Aeronautical Sciences)
301

Leningrad. Glavnaia Geofizicheskaia Obpervatoriia, Trudy

Marconi, Rome

Marconi Review, Chelmsford

Marine Observer, London

Meteorological Magazine, London

Meteorologische Rundschau, Berlin

Meteorologicke Zpravy, Prague

Nachrichtentechnik, Berlin

NTZ. Nachrichtentechnische Zeitschrift, Brunswick

Nature, London

Nederlands Tijdschrift voor Natuurkunde, The Hague

Nordwestdeutscher Rundfunk, Technische Hausmitteilungen, Hamburg

Nuevo Cimento, Bologna

L'Onde Electrique, Paris

Optical Society of America, New York, Journal

Papers in Meteorology and Geophysics, Tokyo

Papers in Physical Oceanography and Meteorology, Cambirdge, Mass.

Philips Technical Review, Eindhoven

Philips Telecommunication Review, Hilversum, The Netherlands

Philosophical Magazine, London

Physica, Amsterdam

Physical Review, New York

Physical Society of Japan, Tokyo, Journal

Physical Society of London, Proceedings

Point to Point Telecommunications, Chelmsford, England

Pure and Applied Mathematics, New York

QST, West Hartford, Conn.

Radio Engineering, New York (English translation of the Russian journal:

Radiotekhnika, Moscow)

Radio Engineering and Electronics, New York

Radio und Fernsehen, Leipzig

Radiotekhnika i Elektronika, Moscow (English transl. by the American Institute

of Electrical Engineers, titled: Radio Engineering and Electronic Physics, N. Y.)

Reviews of Geophysics, Washington, D.C.

Review of Scientific Instruments, New York

Rivista di Meteorologia Aeronautica, Rome

Royal Institution of Great Britain, Proceedings

Royal Meteorological Society, Canadian Branch, Publications

Royal Meteorological Society, London, Q uarterly Journal

Royal Society of London, Philosophical Transactions, Ser. A

Royal Society of London, Proceedings, Ser. A

Royal Society of New Zealand, Transactions

Rundfunktechnische Mitteilungen, Hamburg
302

Science, Wash., D.C.

Scientia Sinica, Peking

Scientific American, New York

Seppyo (Snow and Ice), Tokyo

Services Electronics Research Laboratory, S.E. R.L. Technical Journal, Baldock,

Hertfordshire

Siemens Entwicklungsberichte, Berlin

South African Journal of Science, Johannesburg

Soviet Astronomy AJ, New York

Soviet Physics; Acoustics, New York

Teknisk Ukeblad, Oslo

Tele - Radio, Warsaw

Telecommunications, New York (English translation of Russian journal: Elektrosviaz)

Telefunken Zeitung, Berlin

Telephony, Chicago

Television Society, Journal, London

Tijdschrift van het Nederlandsch Radiogenootschap, Baam

U.S. National Bureau of Standards, Circulars

U.S. National Bureau of Standards, Journal of Research, Wash. ,D.C. ,Sec. D

U.S. National Bureau of Standards, Technical News Bulletin

U.S. National Bureau of Standards, Technical Notes

U.S.S. R. Ministerstvo Vysshego Obrazovaniia, Izvestiia Vysshikh Uchebnykh

Zavedenii, Radiofizika

U. S.S. R. Ministerstvo Vysshego i Srednego Spetsial'nogo Obrazovaniia, Izvestiia

Vysshikh Uchebnykh Zavedenii, Radiofizika

Weatherwise, Boston

Wetter und Leben, Vienna

Wire and Radio Communications, Ridgewood, N.J.

Wireless World, London

Zeitschrift fur Angewandte Physik

Zeitschrift f&r Meteorologie, Berlin

Zeitschrift fur Naturforschung, Wiesbaden

Zhurnal Technicheskoi Fiziki, Moscow

US. GOVERNMENT PRINTING OFFICE . 1965 O —764-279