NBSIR 88-381 51

. National Institute of

Technology on Aug.

the Omnibus Trade

’ness Act was signed.

of technology by U•S.

NEW NIST PUBLICATION

October 18, 1988

Center for Electronics and

Electrical Engineering

Technical

Progress

Bulletin

Covering Center Programs,

January to March 1988,

with 1988 CEEE Events Calendar

July 1988

U.S. Department of Commerce

National Bureau of Standards

National Engineering Laboratory

Gaithersburg, Maryland 20899
INTRODUCTION TO JULY 1988 ISSUE OF THE CEEE TECHNICAL PROGRESS BULLETIN

This is the twenty- second issue of a quarterly publication providing information on

the technical work of the National Bureau of Standards Center for Electronics and

Electrical Engineering. This issue of the CEEE Technical Progress Bulletin covers

the first quarter of calendar year 1988.

Organization of Bulletin: This issue contains abstracts for all Center papers released for publication by NBS in the quarter and citations and abstracts for Center

papers published in the quarter. Entries are arranged by technical topic as identified in the table of contents and alphabetically by first author under each subheading within each topic. Unpublished papers appear under the subheading "Released for

Publication" . Papers published in the quarter appear under the subheading "Recently

Published" . Following each abstract is the name and telephone number of the individual to contact for more information on the topic (usually the first author) . This

issue also includes a calendar of Center conferences and workshops planned for calendar year 1988 and a list of sponsors of the work.

Center for Electronics and Electrical Engineering: Center programs provide national

reference standards, measurement methods, supporting theory and data, and traceability to national standards.

The metrological products of these programs aid economic growth by promoting equity

and efficiency in the marketplace, by removing metrological barriers to improved

productivity and innovation, by increasing U. S. competitiveness in international

markets through facilitation of compliance with international agreements, and by

providing technical bases for the development of voluntary standards for domestic and

international trade. These metrological products also aid in the development of

rational regulatory policy and promote efficient functioning of technical programs of

the Government

.

The work of the Center is divided into two major programs: the Semiconductor Technology Program, carried out by the Semiconductor Electronics Division in Gaithersburg, MD, and the Signals and Systems Metrology Program, carried out by the Electrosystems Division in Gaithersburg and the Electromagnetic Fields and Electromagnetic

Technology Divisions in Boulder, CO. Key contacts in the Center are given on the

back cover; readers are encouraged to contact any of these individuals for further

information. To request a subscription or for more information on the Bulletin,

write to CEEE Technical Progress Bulletin, National Bureau of Standards, Metrology

Building, Room B-358, Gaithersburg, MD 20899 or call (301) 975-2220.

Center sponsors: The Center Programs are sponsored by the National Bureau of Standards and a number of other organizations , in both the Federal and private sectors

;

these are identified on page 29.

Note on Publication Lists: Guides to earlier as well as recent work are the publication lists covering the work of each division. These lists are revised and reissued

on an approximately annual basis and are available from the originating division. The

current set is identified in the Additional Information section, page 26.
CEEE Technical Progress Bulletin - July 1988 Page 1

TABLE OF CONTENTS

INTRODUCTION

SEMICONDUCTOR TECHNOLOGY PROGRAM

inside front cover

. . . .

• . 2

Silicon Materials 2

Analysis Techniques 2

Dimensional Metrology 2

Photodetectors 2

Power Devices 3

Integrated Circuit Test Structures 3

Device Physics and Modeling 4

Insulators and Interfaces 5

Other Semiconductor Metrology Topics 5

FAST SIGNAL ACQUISITION, PROCESSING, & TRANSMISSION 6

Waveform Metrology 6

Cryoelectronic Metrology 8

Laser Metrology 9

Pulse Power Metrology 9

Antenna Metrology 9

Noise Metrology 11

Microwave and Millimeter-Wave Metrology 11

Optical Fiber Metrology 11

Electro-Optic Metrology 11

Complex Testing 12

Other Fast Signal Topics 13

ELECTRICAL SYSTEMS 14

Power Systems Metrology 14

Superconductors 17

Other Electrical Systems Topics 20

ELECTROMAGNETIC INTERFERENCE 21

Radiated Electromagnetic Interference 21

Conducted Electromagnetic Interference 26

ADDITIONAL INFORMATION 26

1988 CEEE CALENDAR 27

SPONSOR LIST 29

KEY CONTACTS IN CENTER, CENTER ORGANIZATION back cover
Page 2

SEMICONDUCTOR TECHNOLOGY

Silicon Materials

Released for Publication

Geist, J., Migdall, A., and Baltes

H . P . , Analytic Representation of the

Silicon Absorption Coefficient in the

Indirect Transition Region.

An eleven-parameter equation is

presented to describe the 298-K

experimental silicon absorption

coefficient data of Weakliem and

Redfield from 1.05 eV to 2.7 eV. The

standard deviation of the difference

between one and the ratio of the values

calculated from this equation to the

Weakliem and Redfield experimental

values for the same photon energies is

2.5 percent.

[Contact: Jon Geist, (301) 975-2066]

Recently Published

Bennett, H.S., Indirect Energy Gap of

Si: Doping Dependence, Properties of

Crystalline Silicon, Chapter 7.3, EMIS

Datareview (Institute of Electrical

Engineers, London, February 1988), pp

174-181.

The doping dependence of the indirect

energy gap of silicon is reviewed for

the Electronic Materials Information

Services (EMIS) of IEE (London) . This

review is a guide with commentary to

assist readers in selecting which values

are best for their applications. Our

state of knowledge in this area is such

that in many cases the intended

application for the data on bandgap

changes determines the appropriate

values to use. Data from interpreting

both electrical and optical measurements

are given.

[Contact: Herbert S. Bennett, (301)

975-2081]

Analysis Techniques

CEEE Technical Progress Bulletin - July 1988

Jach, T. , Novotny, D.B., Carver, G.P.,

Geist, J., and Spal , R.D., An X-Ray

Monochromator Crystal Which Detects the

Bragg Condition, Nuclear Instrumentation and Methods in Physics Research,

Vol. A263 (North-Holland, Amsterdam,

1988), pp. 522-524.

We have fabricated a (111) silicon x-ray

monochromator crystal with a diode

diffused into its surface. Without

suffering any apparent degradation in

its rocking- curve width at the Bragg

condition, the crystal provides a dc

current which changes dramatically at

the diffraction of a monochromatic x-ray

beam. The current change is directly

attributable to extinction at the Bragg

angle. It provides a new means to align

the two crystals of a double-crystal xray monochromator using a feedback

circuit

[Contact: Donald B. Novotny, (301) 975-

2699]

Dimensional Metrology

Released for Publication

Young, M. , Spatial-Filtering Microscope

for Linewidth Measurements

High-pass filtering has been relatively

little used in microscopy, yet it may

have application to linewidth measurement and visualization of phase objects.

I have designed and built a spatialfiltering microscope entirely of

conventional microscope objectives. For

linewidth measurement, the spatial

filter has an optimum width that allows

linewidths to be measured within a few

percent. Phase lines can also be

examined, but phase contrast microscopy

may be more suited to weak phase objects

such as integrated optical waveguides.

[Contact: Matt Young, (303) 497-3223/-

5342]

Photodetectors

Recently Published Released for Publication
CEEE Technical Progress Bulletin - July 1988 Page 3

Photodetectors (cont'd.)

Geist, J., Migdall, A., and Baltes,

H . P . , Analytic Representation of the

Silicon Absorption Coefficient in the

Indirect Transition Region.

An eleven-parameter equation is

presented to describe the 298-K

experimental silicon absorption

coefficient data of Weakliem and

Redfield from 1.05 eV to 2.7 eV. The

standard deviation of the difference

between one and the ratio of the values

calculated from this equation to the

Weakliem and Redfield experimental

values for the same photon energies is

2.5 percent.

[Contact: Jon Geist, (301) 975-2066]

Power Devices

Released for Publication

Blackburn, D.L., Power MOSFET Failure

Revisited, to be published in the PESO

'88 Record, Proceedings of the 1988

IEEE Power Electronics Specialists Conference, Kyoto, Japan, April 11-14,

1988.

The failure of power MOSFETs during

avalanche breakdown is discussed. A

theory is presented that relates the

failure to the temperature rise of the

chip during avalanche breakdown and to a

critical current for failure. It is

shown that the energy that can be

safely dissipated during avalanche

breakdown decreases as the starting

current increases or as the case

temperature increases . Thus , if power

MOSFETs are to be rated for their

energy dissipation capability during

avalanche breakdown, both the starting

current and temperature must be

specified, as it is these two parameters

that determine the failure limits.

[Contact: David L. Blackburn, (301)

975-2068]

Integrated Circuit Test Structures

Released for Publication

Schafft, H.A.

,

Lechner, J.A., Sabi, B.,

Mahaney, M. , and Smith, R.C., Statistics for Electromigration Testing, to

be published in the Proceedings of the

26th Annual Reliability Physics

Symposium, Monterey, California, April

12-14, 1988.

A comprehensive statistical basis is

given for the design and conduct of

electromigration stress tests that

allows for the efficient use of test

parts, equipment, and test time. It

shows how to select the size of the

sample, the required control of the

stress conditions, and the number of

failures required before halting the

test in order to characterize metallization interconnects with a quantifiable

level of confidence. The results are

applicable to any failure mechanism for

which the failure times obey a normal or

a log-normal distribution.

[Contact: Harry A. Schafft, (301) 975-

2234]

Recently Published

Kim, J.S., Linholm, L.W.

,

Barley, B.L.,

Hanes, M.H.

,

and Cresswell, M.W.

,

A

Microelectronic Test Structure for

Thickness Determination of Homogeneous

Conducting Thin Films in VLSI Processing, Proceedings of the 1988 IEEE

International Conference on Microelectronic Test Structures, Long Beach,

California, February 22-23, 1988, pp

.

34-38.

This paper describes a new test

structure for use in determining the

thickness of a uniform conducting film.

The structure incorporates the van der

Pauw cross method to determine the

effective sheet resistance of a

vertical, uniformly doped cross section

of a polysilicon film and a bridge

resistor to determine the thickness of

the film. By using a composite

structure, which consists of the

vertical cross structure and a conventional planar cross-bridge test

structure, it is possible to obtain the

thickness, linewidth, and resistivity of
Page 4

IC Test Structures (cont'd.)

a conducting line.

[Contact: Jin S. Kim, (301) 975-2238]

Buehler, M.G., Linholm, L.W. , Tyree,

V.C., Allen, R.A. , Blaes , B.R., Hicks,

K.A. , and Jennings, G.A., CMOS Process

Monitor, Proceedings of the 1988 IEEE

International Conference on Microelectronic Test Structures, Long Beach,

California, February 22-23, 1988, pp

164-168. [Identical publication

entitled Proposed End-of-Fabrication

Parametric Test Structures for the CMOS

Process Monitor will appear as Jet

Propulsion Laboratory Report #D-4520.]

This document describes a proposed endof-fabrication CMOS process monitor for

VHSIC/VLSI wafer fabrication qualification. The discussion of the CMOS

process monitor includes a description

of the test structures, test methods,

and data analysis techniques needed to

acquire 26 key electrical parameters

that characterize a CMOS process. This

process monitor has been under development for a number of years at JPL's VLSI

Technology Group and the University of

Southern California/Information Sciences

Institute MOSIS Project.

[Contact: Loren W. Linholm, (301) 975-

2052]

Linholm, L.W. , Khera, D., Reeve, C.P.,

and Cresswell, M.W. , A Developmental

Expert System for Test Structure Data

Evaluation, Proceedings of the 1988

IEEE International Conference on

Microelectronic Test Structures, Long

Beach, California, February 22-23,

1988, pp. 160-163.

This paper describes a developmental

expert system, rule generation techniques, a test chip, data handling

methods, and statistical data reduction

techniques for characterizing the

performance of a 1-pm lithography

process. Examples of test results and

an expert system diagnosis are given.

[Contact: Loren W. Linholm, (301) 975-

2052]

CEEE Technical Progress Bulletin - July 1988

Schafft, H.A., and Albers, J., Thermal

Interactions Between Electromigration

Test Structures, Proceedings of the

1988 IEEE International Conference on

Microelectronic Test Structures, Long

Beach, California, February 22-23,

1988, pp. 132-137.

The thermal interaction between

electromigration test structures on a

test chip, when subjected to a high

current-density stress, must be

considered when making median- time- tofailure measurements.

[Contact: Harry A. Schafft, (301) 975-

2234]

Suehle , J.S., and Galloway, K.F., Test

Circuit Structures for Characterizing

the Effects of Localized Hot-CarrierInduced Charge in VLSI Switching

Circuits, Proceedings of the 1988 IEEE

International Conference on Microelectronic Test Structures, Long Beach,

California, February 22-23, 1988, pp

126-131.

Data are presented that were collected

from test circuit structures that were

hot-carrier-stressed under conditions

existing In actual VLSI switching

circuits. It is shown that the

localized nature of hot-carrier- induced

damage to n-channel MOSFETs must be

considered to accurately model these

data by computer circuit simulations.

[Contact: John S. Suehle, (301) 975-

2247]

Device Physics and Modeling

Recently Published

Wilson, C.L., Hydrodynamic Carrier

Transport in Semiconductors with

Multiple Band Minimums, IEEE Transactions on Electron Devices, Vol. 35, No.

2, pp. 180-187 (February 1988).

Carrier transport equations for analysis

of semiconductor devices fabricated in

materials with multiple band minimums,

such as GaAs , are presented. This
CEEE Technical Progress Bulletin - July 1988 Page 5

Device Physics and Modeling (cont'd)

revised formulation has several

advantages over previous models.

Separation of the carrier transport into

central and satellite components

improves numerical stability in

numerical simulations and allows the

physical processes associated with each

band to be modeled in greater physical

detail. This permits processes

previously neglected in hydrodynamic

models, such as electron injection into

insulating substrate material and deep

electron traps in GaAs transistors, to

be included. A model of a GaAs MESFET,

which illustrates the importance of the

new physical effects and achieves

reasonable agreement with experiment

without use of adjustable parameters, is

presented as an example.

[Contact: Charles L. Wilson, (301) 975-

2080]

Insulators and Interfaces

Released for Publication

Dumin, D.J., Dabral, S., Freytag, M. , Robertson, P.J., Carver, G.P., and

Novotny, D.B.

,

Ultra-Thin High Quality

SOS Films for VLSI Applications, to be

published in the Proceedings of the

Symposium on VLSI Technology, San

Diego, California, May 10-13, 1988.

Sub-micron VLSI devices fabricated on

SOI films require very thin, highquality films. At the present time, the

only way SOS films with acceptable

quality have been fabricated has been to

grow the silicon film and then use

successive ion implantations, recrystallizations, etching, and epitaxial

regrowth. The solid-phase epitaxy (SPE)

and regrowth (SPEAR) and double solidphase epitaxy processes have been used

to produce high-quality 0.3-fj.m to 0.5-/im

thick films. However, these processes

certainly add to the cost of an already

expensive substrate. There is need for

a single epitaxial growth process that

will produce high-quality SOS films.

[Contact: Donald B. Novotny, (301) 975-

2699]

Dutta, P., Candela, G.A., ChandlerHorowitz, D., Marchiando, J.F., and

Peckerar, M.C., Nondestructive Characterization of Oxygen-Ion-Implanted

Silicon-on- Insulator Using MultipleAngle Ellipsometry

.

Silicon-on- insulator formed by high-dose

and high-energy oxygen- ion implantation

in silicon, SIMOX, has been characterized nondestructively by multipleangle ellipsometry using a He-Ne laser

at 632.8 nm. A multilayered model

exhibiting two interlayers, one between

the top silicon and the buried oxide and

the other between the buried oxide and

the substrate silicon, offers a good

representation of SIMOX. The distinction between two- temperature furnace

anneal (1150°C) and high- temperature

rapid thermal anneal (1150°C + 1350°C)

on as- implanted wafers is manifested in

terms of the optical properties of these

transition regions. It is shown that

the agreement between the theoretical

model and the experimental results

improves for the high- temperature

annealed SIMOX.

[Contact: Pradip Dutta, (301) 975-

2076]

Other Semiconductor Measurement Topics

Released for Publication

Bouldin, C.E., Bunker, G., McKeown,

D.A. , Forman, R.A. , and Ritter, J.J.,

Multiple Scattering in the XANES [= Xray Absorption Near-Edge Structure] of

Tetrahedral Ge Gases

.

X-ray absorption fine structure (XAFS)

measurements of GeCl4 , Ge^Cl, and GeH4

are made. Since wide-angle multiple

scattering involving H atoms is

negligible, we experimentally isolate

the single- and multiple-scattering

terms in the XAFS of GeCl4 . We find

that multiple scattering (MS) is

nowhere dominant over single scattering

(SS)

,

although within 15 eV of the

absorption edge the two are comparable
Page 6

Other Semiconductor Topics (cont'd.)

CEEE Technical Progress Bulletin - July 1988

in size. However, the multiplescattering term damps out very quickly

with increasing energy above the edge.

Above 40 eV past the edge, the MS/SS

ratio is less than 0.06. Calculations

are found to be in qualitative agreement

with experiment, but they overestimate

the size and energy range of MS.

Results suggest that XAFS data in the

range 1 < k < 3 can be analyzed in

an SS picture in many cases, so long as

good standard compounds are used, and

calculations are used to estimate

possible errors due to neglect of MS.

Also reported is the first evidence of

single scattering observed from H atoms.

[Contact: Charles E. Bouldin, (301)

975-2046]

FAST SIGNAL ACQUISITION, PROCESSING,

AND TRANSMISSION

Waveform Metrology

Released for Publication

Oldham, N.M.Hetrick, P.S., and

Xiangren, Z. , A Calculable, Transportable Audio -Frequency AC Reference

Standard, to be published in the

Conference Digest of CPEM-88, Tsukuba

Science City, Japan, June 7-10, 1988.

A transportable ac voltage source is

described, in which sinusoidal signals

are digitally synthesized in the audiofrequency range . The rms value of the

output waveform may be calculated by

measuring the dc level of the individual

steps used to generate the waveform.

The uncertainty of this calculation is

typically ±10 ppm from 20 Hz to 10 kHz

at the 7-V level.

[Contact: Nile M. Oldham, (301) 975-

2408]

Oldham, N.M.

Petersons, 0., and

Waltrip, B.C., Audio -Frequency CurrentComparator Power Bridge, to be

published in the Conference Digest of

CPEM-88, Tsukuba Science City, Japan,

June 7-10, 1988.

A system for performing active and

reactive power measurements from 50 Hz

to 20 kHz is described. The technique

is an extension of a power bridge based

on a current-comparator capacitance

bridge that was originally restricted to

power frequencies. A digitally

synthesized dual-channel signal source

provides the required voltage and

current signals.

[Contact: Nile M. Oldham, (301) 975-

2408]

Souders , T.M., and Hetrick, P.S.,

Accurate RF Voltage Measurements Using

a Sampling Voltage Tracker, to be

published, in the Conference Digest of

CPEM-88, Tsukuba Science City, Japan,

J une 7-10, 1988.

The radio- frequency (rf) voltage

measurement capability of an equivalent

time-sampling system is described. The

frequency range investigated is 1 to

100 MHz. Over this range, the measured

errors, determined by ac/dc thermal

transfer, are within the stated

uncertainties presently provided by NBS

for thermal converter calibrations. The

system offers several advantages over

conventional thermal transfer techniques: ac/dc transfers are not

required, loading and transmission line

problems are reduced, and direct

measurement of voltages from 2 V to as

low as 10 mV are possible.

[Contact: T. Michael Souders, (301)

975-2406]

Recently Published

Leedy, T.F., and Bell, B.A., Concepts

for ATE Systems Calibration: Transport

Standards to Achieve Traceability to

National Standards, Proceedings of the

1988 Measurement Science Conference,

Long Beach, California, January 23-29,

1988, pp. 307-313.

Technical objectives are presented for a

proposed transport standard to establish

direct traceability of selected lowfrequency electrical quantities between

the National Bureau of Standards and
CEEE Technical Progress Bulletin - July 1988 Page 7

Waveform Metrology (cont'd.)

automatic test systems including

calibration laboratories that support

these automatic test systems. The

transport standard would consist of

precision ac and dc voltage and

frequency sources and could also include

more specialized measurement modules in

future versions. The transport standard

would allow the intercomparison of dc

voltage, ac (root-mean-square) voltage,

total harmonic distortion, phase, and

frequency measurements made using

automatic test equipment systems.

[Contact: Thomas F. Leedy, (301) 975-

2410]

Petersons, 0., NBS Initiatives in

TMDE/ATE Diagnostics, Symposium Record,

National Security Industrial Association Diagnostics/Prognostics Symposium,

Alexandria, Virginia, October 20-21,

1987, pp. 190-193 (1988).

Advances in technology dictate that the

National Bureau of Standards consider

how to provide metrological support for

automatic test equipment (ATE) and the

area of complex systems in general.

Several decades ago, standard instruments were relatively simple devices

such as standard resistors, electrochemical cells for voltage, and relatively

simple electromechanical indicating

meters. Modern precision instruments,

however, such a digital multimeters,

calibrators, and waveform analyzers are

very complex, computer-controlled

systems having a broad spectrum of

parameters including wide frequency and

dynamic ranges and high speeds of

operation. While complete characterization was possible and economical for the

older and simpler standard instruments,

this may not be true for modern

measurement systems. Besides the

calibration itself, consideration must

be given to such items as judicious

selection of a limited number of test

points, test coverage, and confidence

levels. These considerations relate, at

least partly, to the subject of the

Conference. In addition, NBS has strong

interest in the diagnostics of systems

that are required to produce accurate,

reliable, and economical measurements.

Such systems include state-of-the-art

test, measurement, and diagnostic

equipment (TMDE) and ATE as used by

defense forces.

This presentation outlines several

activities along the lines described

above that are conducted at NBS,

particularly in the Electrosystems

Division. First, some basic tools and

expertise that are applicable to TMDE

and ATE diagnostics are discussed,

followed by examples of applications,

particularly to DoD systems and TMDE.

[Contact: Oskars Petersons, (301) 975-

2400]

Turgel, R.S., Phase Meter Calibration at

NBS, Journal of Research of the

National Bureau of Standards, Vol. 93,

No. 1, pp. 53-60 (January- February

1988)

.

To provide a phase meter calibration

service, a phase angle calibration

standard has been developed at NBS.

This standard is a signal generator with

two sinusoidal outputs and uses direct

digital synthesis to generate the

signals. The phase angle between the

two sinusoids is determined by the input

parameters in the calculation of the

sets of digital values from which the

analog output is synthesized. An autozero compensation mode corrects for

residual phase differences in the two

output channels. The phase resolution

is better than 0.002 deg over a

frequency range from 2 Hz to 5 kHz and

0.005 deg from 5 kHz to 50 kHz.

Phase meter calibration data are fitted

to a linear model from which appropriate

corrections for the phase meter readings

can be derived. Statistical treatment

of the data provides an estimate of the

uncertainty of the corrected phase meter

readings relative to the phase angle

calibration standard.

[Contact: Raymond S. Turgel, (301) 975-

2420]
Page 8

Waveform Metrology (cont'd.)

CEEE Technical Progress Bulletin - July 1988

Turgel , R.S., Laug, O.B., and Leedy,

T.E., Electrical Performance Tests for

True -RMS Voltmeters, NBSIR 88-3736

(March 1988)

Electrical performance test procedures

for a true root-mean-square (rms)

voltmeter were developed by the National

Bureau of Standards for the U.S. Army

Communications-Electronics Command. The

report provided detailed, step-by-step

test procedures that are based on the

specifications supplied by the Army for

the purpose of evaluating the bid

samples of this type of instrument.

Examples are provided of the data sheets

and tables for recording of interim data

and the final results.

This report discusses the philosophy

underlying each of the measurement

procedures from a point of view of the

basic metrology required to perform the

measurements. In addition, the sources

of measurement error are discussed.

[Contact: Raymond S. Turgel, (301) 975-

2420]

Crvoelectronic Metrology

Released for Publication

Hu, Q. , Mears, C.A., Richards, P.L., and

Lloyd, F.L.Measurement of Integrated

Tuning Elements for SIS Mixers with a

Fourier Transform Spectrometer.

Planar lithographed quasi-optical mixers

can profit from the use of integrated

tuning elements to improve the coupling

between the antenna and the superconductor-insulator-superconductor (SIS) mixer

junctions. We have used a Fourier

transform spectrometer with an Hg-arc

lamp source as a radio-frequancy (rf)

sweeper to measure the frequency

response of such integrated tuning

elements. The SIS junction connected to

the tuning element served as the direct

detector for the spectrometer. This

relatively quick, easy experiment can

give enough information over a broad

range of millimeter and submillimeter

wavelengths to test both design concepts

and success in fabrication. One type

of tuning element, an inductive wire

connected in parallel with a series

array of five SIS junctions across the

terminals of a bow-tie antenna, shows a

resonant response peak at 100 GHz with a

30% bandwidth. This result is in

excellent agreement with theoretical

calculations based on a simple inductance-capacitance circuit. It also

agrees very well with the rf frequency

dependence of the mixer gain measured

using the same structure. The other

type of tuning element, an opencircuited stub connected in parallel

with a single SIS junction across the

terminals of a bow-tie antenna, exhibits

multiple resonances at 110, 220, and 336

GHz, with bandwidths of 9 to 15 GHz.

This result is in good agreement with

theoretical calculations based on an

open-circuited stub with small loss and

small dispersion. The position and the

bandwidth of the resonance at 110 GHz

also agrees with the rf frequency

dependence of the mixer gain measured

using similar structures.

[Contact: Frances L. Lloyd, (303) 497-

3254]

Kautz , R.L.

Thermally Induced Escape:

The Principle of Minimum Available

Noise Energy.

The average time required for thermally

induced escape from a basin of attraction increases exponentially with

inverse temperature in proportion to

exp (E^/kT) in the limit of low

temperature. A minimum principle states

that the activation energy E^ is the

minimum available noise energy required

to execute a state- space trajectory

which takes the system from the

attractor of the noise-free system to

the boundary of its basin of attraction

and that the minimizing trajectory is

the most probable low- temperature escape

path. This principle is applied to the

problem of thermally induced escape from

two attractors of the dc-biased

Josephson junction, the zero-voltage
CEEE Technical Progress Bulletin - July 1988 Page 9

Crvoelectronic Metrology (cont'd.)

state and the voltage state, to

determine activation energies and most

probable escape paths. These two escape

problems exemplify the classical case of

escape from a potential well and the

more general case of escape from an

attractor of a nonequilibrium system.

Monte Carlo simulations are used to

verify the accuracy of the activation

energies and the most probable escape

paths derived from the minimum principle . [Contact: Richard L. Kautz , (303) 497-

3391/-3988

]

Laser Metrology

Released for Publication

Scott, T.R., Review of NBS Laser Power

and Energy Measurements

.

The National Bureau of Standards (NBS)

maintains a set of electrically

calibrated calorimeters designed and

used for laser energy measurements

.

These calorimeters are used as national

reference standards for the calibration

of optical power and energy meters.

Based on the standard calorimeters and

associated measurement systems, NBS

offers laser power and energy measurement services to the public at a

variety of laser wavelengths and power

ranges. The uncertainties associated

with these measurements have recently

been reevaluated.

[Contact: Thomas R. Scott, (303) 497-

3651]

Pulse Power Metrology

Released for Publication

McComb, T.R.

,

Hughes, R.C., Lightfoot,

H.A.

,

Schon, K. , Schulte, R. , McKnight,

R.B. , and Zhang, Y.X.

,

International

Comparison of HV Impulse Measuring

Systems

.

Present standards for qualifying highvoltage (HV) impulse measuring systems

by unit-step-response parameters are

complex and difficult to apply, and some

systems, which have response parameters

within the limits of the standards, have

unacceptable errors. This paper takes

the first step in providing a simplified

method based on simultaneous measurements of an HV impulse by a reference

system and the system under test.

Comparative measurements have been made

in four national laboratories and the

relative differences are reported. The

results are discussed, and the further

work which is required is outlined.

[Contact: William E. Anderson, (301)

975-2423]

Antenna Metrology

Released for Publication

Baird, R.C., Newell, A.C., and Stubenrauch, C.F., A Brief History of NearField Measurements of Antennas at the

National Bureau of Standards.

The National Bureau of Standards (NBS)

played a pioneering role in the

development of practical planar nearfield antenna measurement techniques.

This paper presents a brief history of

that role, which began with theoretical

studies to determine corrections for

diffraction in a microwave measurement

of the speed of light. NBS contributions to the development of nonplanar

near- field measurement theory and

practice are also described.

[Contact: Ramon C. Baird, (303) 497-

3131]

Camell, D.G., Larsen, E.B., and Anson,

W.J., NBS Calibration Procedures for

Horizontal Dipole Antennas (25 to 1000

MHz) , to be published in the Symposium

Record of the 1988 IEEE International

Symposium on Electromagnetic Compatibility, Seattle, Washington, August

2-4, 1988.

The theoretical basis and test procedures for horizontally polarized dipole

calibrations at the National Bureau of

Standards are described. Two different
Page 10

Antenna Metrology (cont'd.)

CEEE Technical Progress Bulletin - July 1988

techniques and two different test sites

are used for these measurements. The

standard antenna method uses the

calculation of a field strength level,

from the response of a simple half-wave

dipole, to calibrate an antenna. This

method is used at an open-field site in

the frequency range 25 to 1000 MHz. The

standard field method applies the

theoretical gain equations of waveguides

to determine the field strength level.

This latter method is used in an

anechoic chamber in the frequency range

200 to 1000 MHz. Procedures for both

techniques are explained and measurement

setups are illustrated. Measurement

uncertainties are discussed.

[Contact: Dennis G. Camell, (303) 497-

3214]

Recently Published

Hill, D.A. , and Francis, M.H., Out-ofBand Response of Antenna Arrays, IEEE

Transactions on Electromagnetic

Compatibility, Vol. EMC-29, No. 4, pp

282-288 (November 1987) . [Also

appeared in the Proceedings of the 1987

IEEE International Symposium on

Electromagnetic Compatibility,

Symposium Record, August 25-27, 1987,

Atlanta, Georgia, pp . 435-438. An

expanded version appeared as NBSIR 86-

2037 (June 1986).]

The response of antenna arrays to outof-band frequencies has been analyzed

using the effective aperture approach.

An average value of effective aperture

can be obtained by averaging the

incidence angle and the polarization of

the incident field. Far-field patterns

have also been calculated by treating

the array element excitations as random

variables. The randomness in the

element excitations causes a decrease in

directivity and an increase in sidelobe

level

[Contact: David A. Hill, (303) 497-

3472]

R.L. , Spherical -Wave SourceScattering Matric Analysis of Coupled

Antennas; A General System Two-Port

Solution, IEEE Transactions on Antennas

and Propagation, Vol. AP-35, No. 12,

pp . 1375-1380 (December 1987).

Expressions are given for the coupling

between two antennas in terms of each

antenna's spherical-wave sourcescattering matrix. A comparison with

the "classical" scattering matrix

representation is given in sufficient

detail to permit conversion back and

forth between the source-scattering

matrix and the classical scattering

matrix. The paper concludes with

expressions for the transmission

formulas, showing two different

expressions corresponding to reversing

the direction of propagation. However,

if both antennas are reciprocal with

equal characteristic waveguide impedances, then the two-port scattering

matrix is a symmetric matrix.

[Contact: Richard L. Lewis, (303) 497-

5196]

Lewis, R.L., and Wittmann, R.C.,

Improved Spherical and Hemispherical

Scanning Algorithms, IEEE Transactions

on Antennas and Propagation, Vol. AP35, No. 12, pp. 1381-1388 (December

1987) .

A probe-corrected spherical- scanning

algorithm has been developed which is

applicable when the antenna under test

radiates negligibly into its rear

hemisphere. Compared to an efficient

version of the best previously published

full-sphere scanning algorithm, it is

found that our hemispherical scanning

algorithm is over three and a half

times more efficient. Improvements have

also been made to full-sphere scanning,

with the result that our new spherical

scanning algorithm is twice as efficient

as the best previous full -sphere

algorithm. We also show that our new

formulations constitute an exact

inversion of the band- limited sphericalcoordinate representation of the

received signal (i.e., no aliasing

errors are introduced)

Lewis
CEEE Technical Progress Bulletin - July 1988 Page 11

Antenna Metrology (cont'd.)

[Contact: Richard L. Lewis, (303) 497-

5196]

Noise Metrology

Released for Publication

Daywitt, W.C., Design Considerations for

an Accurate Coaxial Noise Standard.

This summary outlines the important

aspects of the design and construction,

and the output noise temperature

calculation, of a cryogenic thermal

noise standard. The coaxial standard

operates up to 12.4 GHz.

[Contact: William C. Daywitt, (303)

497-3720]

Wait, D.F., Daywitt, W.C., and Counas

,

G. , Intercomparison of NBS Noise

Calibration Services.

New, less restrictive thermal noise

calibration services recently established in the frequency range of 2

to 12.4 GHz overlap prior NBS services

and provide an opportunity for intercomparison. The agreement between old and

new calibration systems is better than

0.4%.

[Contact: David F. Wait, (303) 497-

3610]

Microwave and Millimeter-Wave Metrology

Released for Publication

Hill, D.A. , Reflection Coefficient of a

Waveguide with Slightly Uneven Walls.

First-order results are derived for the

reflection coefficient of a waveguide

with slightly uneven walls. Specific

analytical and numerical results are

given for rectangular waveguides and

coaxial transmission lines. Simple

upper bounds are given for reflection

coefficients in terms of the maximum

deviation of the waveguide. For typical

tolerances, the reflection coefficients

are very small (<10 -> ) , but the results

are important in precise six-port

measurements

.

[Contact: David A. Hill, (303) 497-

3472]

Hoer, C.A., An Equivalent Circuit for

Imperfect Transmission Line Connectors.

An exact equivalent circuit for a pair

of transmission line connectors is

developed. New reference planes are

chosen in such a way that all imperfections in the connector pair can be

lumped into one connector or the other.

This makes it possible to compensate for

imperfections in test port connectors

when calibrating network analyzers.

[Contact: Cletus A. Hoer, (303) 497-

3705]

Holt, D.R., Determination of Scattering

Parameters from Precision Coaxial AirLine Standards

.

Scattering parameter expressions are

developed for the principal mode of a

coaxial air line. Dimensional variations in the inner and outer conductors

and skin effect are included in the

model. An error analysis reveals that

accuracy of the scattering parameters is

primarily dependent on the precision of

the measurements of conductor radii.

[Contact: Donald R. Holt, (303) 497-

3574]

Optical Fiber Metrology

Released for Publication

Oates, C.W., and Young, M. , Profile

Inhomogeneity in Multimode -Graded Index

Fibers

.

We have measured the profile parameter

of multimode-graded index fibers and

found that it may vary azimuthally by

0.15 or more

.

[Contact: Matt Young, (303) 497-3223/-

5342]

Electro-Optic Metrology

Released for Publication
Page 12

Electro-Optic Metrology (cont'd.)

CEEE Technical Progress Bulletin - July 1988

Day, G.W.

Lee, K.S., Rose, A.H.,

Veeser, L.R., Papatheofanis , B.J., and

Whitesel, H.K.

Optical Fiber Sensors

for Electromagnetic Quantities , to be

published in the Proceedings of the

Fiber Optics Conference 88, McLean,

Virginia, March 22-25, 1988; and the

Proceedings of the Instrument Society

of America Annual Conference, Albuquerque, New Mexico, May 2-6, 1988.

Several sensors used for the measurement

of both pulsed and ac current, voltage,

and magnetic field are described.

Design considerations, including the

choice of components and configurations,

and performance achievements are

discussed.

[Contact: Gordon W. Day, (303) 497-

5204]

Hickernell, R.K. , Larson, D.R., Phelan,

R.J., Jr., and Larson, L.E., Waveguide

Loss Measurement Using Photothermal

Deflection, to be published in the

Proceedings of the Topical Meeting on

Integrated and Guided Wave Optics

(IGWO'88), Sante Fe, New Mexico, March

25-April 1, 1988.

Photothermal deflection (PTD) is

introduced as a technique for measuring

propagation loss in optical channel

waveguides . A probe laser beam is

deflected by the thermally induced

refractive- index gradient due to the

absorption of guided pump light. The

technique is noncontact and is applicable to a wide range of channel

waveguide geometries and materials,

including buried guides. Scattering

centers and unguided background light

affect the measurement only indirectly,

since the PTD signal depends on the

gradient of the local temperature and

not the light intensity directly.

The pump beam from a HeNe laser of 633-

nm wavelength was mechanically chopped

and coupled into potassium, ionexchanged, glass waveguides. The probe

beam, also of 633-nm wavelength, was

focused on the substrate surface, and

its deflection was measured by a silicon

bicell using lock-in detection. Our

measurements of the PTD signal as a

function of the probe spot position

agree with similar measurements

performed on bulk materials by other

researchers. Scans of the PTD signal as

a function of distance along the

waveguide yielded propagation loss

measurements with lower uncertainty than

scans of the scattered light intensity.

The PTD technique should be useful in

the study of waveguide loss mechanisms.

[Contact: Robert K. Hickernell, (303)

497-3455]

Lee, K.S., and Day, G.W., Effect of

Multiple Internal Reflections on the

Stability of Electro-Optic and MagnetoOptic Sensors.

The effects of multiple internal

reflections are evaluated analytically.

Response functions showing changes in

shape as a function of optical path

length are computed. The variation in

sensitivity is obtained as a function

of the reflectance of the sensing

element and is found to be significant

(several tenths of a percent) even when

the reflectance is reduced to 0.1%.

[Contact: Kyung Lee, (303) 497-5170]

Complex Testing

Recently Published

Petersons, 0., MBS Initiatives in

TMDE/ATE Diagnostics, Symposium Record,

National Security Industrial Association Diagnostics/Prognostics Symposium,

Alexandria, Virginia, October 20-21,

1987, pp. 190-193 (1988).

Advances in technology dictate that the

National Bureau of Standards consider

how to provide metrological support for

automatic test equipment (ATE) and the

area of complex systems in general.

Several decades ago, standard instruments were relatively simple devices

such as standard resistors, electrochemical cells for voltage, and relatively
CEEE Technical Progress Bulletin - July 1988

Complex Testing (cont'd.)

Page 13

simple electromechanical indicating

meters. Modern precision instruments,

however, such a digital multimeters,

calibrators, and waveform analyzers are

very complex, computer-controlled

systems having a broad spectrum of

parameters including wide frequency and

dynamic ranges and high speeds of

operation. While complete characterization was possible and economical for the

older and simpler standard instruments,

this may not be true for modern

measurement systems. Besides the

calibration itself, consideration must

be given to such items as judicious

selection of a limited number of test

points, test coverage, and confidence

levels. These considerations relate, at

least partly, to the subject of the

Conference. In addition, NBS has strong

interest in the diagnostics of systems

that are required to produce accurate,

reliable, and economical measurements.

Such systems include state-of-the-art

test, measurement, and diagnostic

equipment (TMDE) and ATE as used by

defense forces.

This presentation outlines several

activities along the lines described

above that are conducted at NBS

,

particularly in the Electrosystems

Division. First, some basic tools and

expertise that are applicable to TMDE

and ATE diagnostics are discussed,

followed by examples of applications,

particularly to DoD systems and TMDE.

[Contact: Oskars Petersons, (301) 975-

2400]

Other Fast Signal Topics

Released for Publication

Hill, D.A.

,

Fields of Horizontal

Currents Located Above the Earth.

The plane -wave spectrum technique is

used to derive the fields of horizontal

currents located in a horizontal plane

above the earth. The far field is

derived asymptotically, and the near

field is computed by two-dimensional

fast Fourier transform. Specific

numerical results are presented for a pair of oppositely directed dipoles, and

the results have application to

detection of buried objects. When the

antenna is located at low heights, the

field is enhanced in the earth and

decreased in air.

[Contact: David A. Hill, (303) 497-

3472]

Hill, D.A., Magnetic Dipole Excitation

of a Long Conductor in a Lossy Medium.

Formulations for the excitation of

currents on an infinitely long conductor

by electric or magnetic dipoles of

arbitrary orientation are presented.

The conductor can be either insulated or

bare to model ungrounded or grounded

conductors. Specific calculations are

presented for a vertical magnetic dipole

source because this source produces the

appropriate horizontal polarization and

could be used in a borehole- to-borehole

configuration. Numerical results for

the induced current and secondary

magnetic field indicate that long

conductors produce a strong anomaly over

a broad frequency range . The secondary

magnetic field decays slowly in the

direction of the conductor and eventually becomes larger than the dipole source

field.

[Contact: David A. Hill, (303) 497-

3472]

Young, M. , Fresnel Lenses Display

Inherent Vignetting.

Some of the light refracted by a facet

of a Fresnel lens impinges on the axial

(or horizontal) portion of the facet and

is directed away from the focal point.

Loss of this light may be significant in

applications where precise radiometric

measurements are necessary.

[Contact: Matt Young, (303) 497-3223/-

5342]

Recently Published

Bell, B.A.

,

Stenbakken, G.N. , Flynn,
Page 14

Other Fast Signal Topics (cont'd.)

D.R. , Evans, D.J., Burnett, E.D.,

Nedzelnitsky , V. , and Eberhardt, K.R.

Evaluation of a Copy Prevention Method

for Digital Audio Tape Systems, NBSIR

88-3725 (February 1988).

The National Bureau of Standards in

response to requests from the U.S.

Congress tested a system designed to

prevent unauthorized copying by digital

audio tape (DAT) recorders of suitably

encoded audio recordings. The system,

designed by CBS Records, filters out a

narrow range of frequencies from the

spectrum of the original sound in the

region of 3840 Hz, thereby encoding the

material with a "notch" in the frequency

spectrum so that a DAT recorder equipped

with the system's decoding circuitry can

sense the presence of a prescribed notch

in the spectrum and inhibit recording.

The congressional questions and the NBS

conclusions are:

1 . Does the copy prevention system

achieve its purpose?

NBS Conclusion : The system does not

achieve its stated purpose.

2 . Does the system diminish the quality

of the prerecorded material into which

the notch is inserted?

NBS Conclusion : The system's encoder

alters the original electrical signal.

For some listeners for some selections,

this results in a discernible difference

between prerecorded notched and

unnotched material.

3 . Can the system be bypassed and, if

so, how easily?

NBS Conclusion : The copy prevention

system can be bypassed easily.

[Contact: Barry A. Bell, (301) 975-

2402]

Jesch, R.L., Fixed and Base Station FM

Transmitters, National Institute of

Justice, NIJ Standard-0201.01 (September 1987) .

This document establishes minimum

performance requirements and methods of

test for fixed and base station

CEEE Technical Progress Bulletin - July 1988

frequency-modulated (FM) transmitters.

The standard applies primarily to the

law enforcement community, and as such

covers the four frequency bands, 25 to

50 MHz, 150 to 174 MHz, 400 to 512 MHz,

and 806 to 866 MHz. This standard

supersedes NILECJ-STD-0201 . 00 , Fixed and

Base Station FM Transmitters.

[Contact: Ramon L. Jesch, (303) 497-

3496]

ELECTRICAL SYSTEMS

Power Systems Metrology

Released for Publication

Fenimore, C . , The Thermal -Expansive

Growth of Prebreakdown Streamers in

Liquids, to be published in the

Proceedings of the 1988 IEEE International Symposium on Electrical Insulation, Boston, Massachusetts, June 6,

1988.

The growth of electrically conductive,

low-density regions has been observed

in dielectric breakdown in a variety of

liquids. This phenomenon motivates the

development of the present theory for

coupling thermal effects with fluid

mechanical effects in the dynamics of

elongated, impulsively driven bubbles.

The model explicitly describes the timedependent dimensions of a growing

ellipsoidal bubble. The parameters of

the model are the external pressure in

the liquid, the density of energy which

is deposited impulsively in the liquid,

and the length over which energy is

deposited.

In previous work, we have developed a

model for such effects associated with

the growth of a bubble about an arc in a

liquid. In the case of the prebreakdown

streamer, the geometry is not as simple

as for an arc, and the evolution of the

bubble is found in ellipsoidal coordinates. The effect of pressure is to

shorten the time scale of the bubble

dynamics . Even in the case when the

bubble may not be spatially resolved,

the time to recollapse can be es-
CEEE Technical Progress Bulletin - July 1988 Page 15

Power Systems Metrology (cont'd.)

tablished from visual data. Calculations based on the model are shown to be

consistent with experimental results on

the collapse of the streamer.

[Contact: Charles Fenimore , (301) 975-

2428]

Hebner, R.E., Measurement of Electrical

Breakdown in Liquids, to be published

in the Proceedings of the NATO Advanced

Study Institute on the Liquid State and

Its Electrical Properties, Sintra,

Portugal, July 5-17, 1987.

The continuing development of light

sources, high-speed cameras, and highspeed electronic measuring systems have

made it possible to study the breakdown

process in increasing detail. The four

measurements described are high-speed

photography of the breakdown process,

measurement of the voltage and current,

optical spectroscopy, and the measurement of acoustic emission. After a

battery of measurement techniques has

been developed, understanding of the

breakdown process is gained by changing

the system in known ways and determining

the effect of these changes on the

measured results. Parameters which have

been investigated include types of

liquids, chemical additives, particle

density, pressure, viscosity, and the

rate of rise of the applied voltage.

These investigations have led to the

identification of four modes of growth

when the streamer initiates at a cathode

and three modes when it initiates at an

anode

.

[Contact: William E. Anderson, (301)

975-2423]

Misakian, M. , DC Electric Field Effects

During Measurements of Monopolar Charge

Density and Net Space Charge Density

Near HVDC Power Lines.

The influence of a dc electric field on

the measurement of monopolar charge

densities using an aspirator- type ion

counter and the measurement of net space

charge density using a Faraday cage or

filter are examined. Optimum configurations which minimize the effect of the

electric field are identified for each

type of instrumentation.

[Contact: Martin Misakian, (301) 975-

2426]

Misakian, M. , Measurement of Electrical

Parameters Near AC and DC Power Lines,

to be published in the Proceedings of

the IEEE Instrumentation and Measurement Technology Conference, San Diego,

California, April 19-22, 1988.

This presentation surveys the instrumentation, calibration procedures,

measurement techniques, and measurement

standards which can be used for

characterizing (1) fields near ac power

lines and (2) electric field strength,

ion current density, monopolar charge

density, and net space charge near dc

power lines.

[Contact: Martin Misakian, (301) 975-

2426]

Misakian, M. , and McKnight, R.H.

,

DC

Electric Field Effects During Measurements of Monopolar Charge Density and

Net Space Charge Density.

The influence of a dc electric field on

the measurement of monopolar charge

densities using an aspirator- type ion

counter and the measurement of net space

charge density using a Faraday cage or

filter is examined. Optimum configurations which minimize the effect of the

electric field are identified for each

type of instrumentation.

[Contact: Martin Misakian, (301) 975-

2426]

Moore, W.J.M., So, E., Miljanic, P.N.,

Oldham, N.M.

,

and Bergeest, R. , An

International Comparison of Power Meter

Calibrations Conducted in 1987, to be

published in the Conference Digest of

CPEM-88, Tsukuba Science City, Japan,

June 7-10, 1988.

The results of an intercomparison of

power meter calibrations conducted

during 1987 between the National
Page 16

Power Systems Metrology (cont'd)

Research Council, Ottawa (Canada), the

National Bureau of Standards, Gaithersburg (U. S . A. ) , and the PhysikallschTechnische Bundesanstalt , Braunschweig

(Federal Republic of Germany) , using a

time-division multiplier watt-converter

developed at the Institut Mihailo Pup in,

Belgrade (Yugoslavia), are discussed.

The measurements were made at 120 V, 5

A, 50 and 60 Hz, at power factors of

1 . 0 , 0.5 lead and lag, and 0.0 lead and

lag. An agreement between laboratories

of better than 20 parts in a million is

indicated.

[Contact: Nile H. Oldham, (301) 975-

2408]

Olthoff, J.K., Collisions! Electron

Detachment Cross Section Measurements

for SFg, SFg, and F" in SFg: Implications for Interpretations of Existing

Ion Transport and Breakdown Probability

Data, to be published in the Proceedings of the 9th International Conference on Gas Discharges and Their

Applications, Venice, Italy, September

19-23, 1988.

Collisional electron detachment cross

sections for SFg, SF5 , and F" on SF5

target gas have been measured for

relative (center-of-mass) energies in

the range of 3 to 250 eV. Apparent

thresholds for direct detachment are

observed at 90 eV for SF5 and SF5 , and

at 8 eV for F" . Cross sections for ion

conversion processes that compete with

detachment are also reported. The

measured cross sections are used in a

theoretical model which invokes

detachment from long-lived energetically

unstable states of collisionally

excited SFg to explain the pressure

dependence of previously measured

detachment coefficients and the high

apparent detachment thresholds implied

by analysis of breakdown probability

data for SFg. The present results also

indicate the necessity to re-examine ion

conversion rates determined in SF5 from

drift- tube data.

[Contact: James K. Olthoff, (303) 497-

CEEE Technical Progress Bulletin - July 1988

2427]

Pace, M.O.

Wintenberg, A.L., Blalock,

T.V., Foust, J.V., Kelley, E.F.,

Nehmadi , M. , and Hebner, R.E., Measurement of Partial Discharges in Hexane

Under DC Voltage.

Partial discharges in liquid hexane are

observed at the tip of a needle-sphere

electrode system subjected to dc high

voltage. A sensitive amplifier monitors

the partial discharge current and

activates a circuit which operates a

high-speed, high-magnification photography system. The initiation and

growth of the partial discharges is

being photographed and correlated with

the current supplied to the partial

discharge. The initiation of the random

phenomena is photographed by the use of

an image-preserving optical delay.

[Contact: Edward F. Kelley, (301) 975-

2424]

Van Brunt, R.J., and Kulkarni , S.V., New

Method for Measuring the Stochastic

Properties of Corona and Partial

Discharge Pulses, to be published in

the Proceedings of the 1988 IEEE

International Symposium on Electrical

Insulation, Boston, Massachusetts, June

7, 1988.

A new computer-based method for

measuring the statistical characteristics of corona or partial discharge

pulses is described. The method allows

direct measurement of a set of conditional probability distributions that

reveal correlations among successive

pulse amplitudes, pulse time intervals,

and between pulse amplitudes and time

intervals. Application of the method to

an investigation of ultraviolet

sustained negative corona (Trichel)

pulses in air has shown the existence of

strong correlations between pulse

amplitude and time interval as well as

between amplitudes of successive pulses.

The observed correlations appear to be

consistent with existing models for

Trichel pulse formation.

[Contact: Richard J. Van Brunt, (301)
CEEE Technical Progress Bulletin - July 1988 Page 17

Power Systems Metrology (cont'd.)

975-2425]

Van Brunt, R.J., and Kulkarni , S.V.,

Stochastic Properties of Negative

Corona (Trichel) Pulses in SF5/O2

Mixtures, to be published in the

Proceedings of the 9th International

Conference on Gas Discharges and Their

Applications: Venice, Italy, September

19-23, 1988.

The statistical probability distributions of discharge pulse amplitude,

p 0 (q) , pulse time interval, p 0 (At), and

pulse amplitude for a given time

separation, At, from the previous pulse,

p^(q|At) have been measured for Tricheltype negative point-plane corona in

SFg /02 gas mixtures as functions of

point- to-plane voltage and mixture

ratio. The results reveal significant,

previously unrecognized correlations

among the amplitudes and time intervals

of successive discharge pulses which are

consistent current theoretical descriptions of the phenomenon. As the SFg

content in SFg /02 mixtures is increased,

the growth of negative corona pulses

diminishes as reflected in lower mean

pulse amplitudes and the pulses appear

more randomly in time; i.e., there is a broadening of the pulse time- interval

distributions

.

[Contact: Richard J. Van Brunt, (301)

975-2425]

Recently Published

Martzloff, F.D., Power Quality Measurements : Bringing Order Out of Chaos

,

Energy Technology XV -- Repowering

America (Proceedings of the Energy

Technology Conference, Washington, DC,

February 17-19, 1988) (Government

Institutes, Inc., Maryland), pp. 947-

959.

The quality of the power supplied to

sensitive electronic equipment is an

important issue. Quantifying this

quality, however, is difficult under the

present state of nonexistent or

uncoordinated standards concerning two

related questions: ( 1 ) what levels of

power quality are required for what

types of loads, and ( 2 ) what measurement

techniques are required to determine

reliably the level of disturbances that

reduce quality. Development of

standards by the consensus process and

voluntary compliance, although a slow

process, is a mechanism for reaching

technically sound and cost-effective

solutions. Several standards projects

are in progress, but need industrywide support to become the generally

accepted basis for valid and useful

measurements of power quality.

[Contact: Francois D. Martzloff, (301)

975-2409]

Sieck, L.W.

,

and Van Brunt, R.J., Rate

Constants for F" Transfer from SFg to

Fluorinated Gases and SO2

. Temperature

Dependence and Implications for

Electric Discharge in SFg, Journal of

Physical Chemistry, Vol. 92, No. 3, pp

.

708-713 (1988).

The reactivity of SFg" towards SO2 , SOF2 , SO 2 F5 , SOF4 , SF4 , and SiF4 has

been investigated using the technique of

pulsed-electron-beam, high-pressure mass

spectrometry. With the exception of the

SFg” + SiF4 reaction, all of the pairs

exhibited a negative temperature

coefficient in that the rate constants

for F” transfer decreased substantially

with increasing temperature. The

reaction SFg” + SiF4 - SiF5

_ + SF5 was

found to proceed with a rate constant of

5.6 ± 0.8 x 10”

^

cm^/mol-s throughout

the temperature range studied (298 to

510 K)

,

which corresponds to a collision

efficiency of unity. The other

reactions were found to approach unit

collision efficiency only at reduced

temperatures (<300 K)

.

[Contact: Richard J. Van Brunt, (301)

975-2425]

Superconductors

Released for Publication

Goldfarb, R.B.

,

Ried, D.L.

,

Kreilick,
Page 18

Superconductors (cont'd.)

CEEE Technical Progress Bulletin - July 1988

T.S., and Gregory, E. , Magnetic

Evaluation of Cu-Mn Matrix Material for

Fine-Filament Nb-Ti Superconductors.

Copper-manganese alloys have been

proposed as matrix material for the

reduction of coupling losses in finefilament Nb-Ti superconductor wires.

Magnetization and susceptibility

measurements show that adverse magnetic

effects arising from the spin-glass

properties of this matrix are minimal

for concentrations of Mn up to at least

4%.

[Contact: Ronald B. Goldfarb, (303)

497-3650]

Goodrich, L.F., Development of Standards

for Superconductors, to be published as

NBSIR 88-3088.

A cooperative program with the Department of Energy, the National Bureau of

Standards, other national laboratories,

and private industry is in progress to

develop standard measurement practices

for use in large-scale applications of

superconductivity. Research for the

period January 1986 through December

1987 is described. This report contains

the results of critical-current studies

on the effect of power supply current

ripple, measurements on single strands

extracted from cables, a round robin on

a large NbTi monolithic conductor, and a

Nb 3 Sn round robin. Several useful

current supply circuits have been

developed. The reduction coupling

losses in multifilamentary NbTi

conductors has been addressed by a study

of the magnetic properties of matrix

material consisting of dilute alloys of

Mn in Cu. In addition, the technique of

vibrating- sample magnetometry is shown

to be adaptable to the measurement of

coupling losses in addition to hysteresis losses in multifilamentary conductors . [Contact: Loren F. Goodrich, (303) 497-

3143]

Moreland, J., Beall, J.A., Ono, R.H. ,

and Clark, A.F., Recent Tunneling

Measurements of 90 K Superconductors at

NBS, to be published in the Proceedings

of Materials Research Society Spring

Meeting, Symposium K, High-Tc Superconductors, Reno, Nevada, April 5-9, 1988.

Several tunneling measurements on oxide

superconductors have been made at NBS

in the last year. These include break

junction tunneling measurements of the

energy gap, break junction superconducting point contacts, and the operation of

a break junction point contact radiofrequency superconducting quantum

interference device (SQUID) above 77 K.

Until recently, these tunneling

experiments have been limited to bulk

samples cut from sintered pellets and a

few small single crystals. We present

here further results on thin films of

YBa2 Cu30x

(YBCO) using squeezable

electron tunneling (SET) junctions. In

contrast to the break junction tunneling

experiments on bulk samples, where quite

often tunneling spectra are without

energy gap features, the spectra for

thin-film SET junctions are rich with

structure

[Contact: John Moreland, (303) 497-

3641]

Moreland, J., Clark, A.F., Damento,

M.A.and Gschneider, Jr., K.A.

Single

Crystal HoBa2Cu30x Break Junctions, to

be published in the Proceedings of the

International Conference on High

Temperature Superconductors - Materials

and Mechanisms of Superconductivity,

Interlaken, Switzerland, February 29-

March 4, 1988.

Tunneling spectra of HoBa2 Cu30x single

crystals using the break junction

method show energy gap features. These

features are variable from junction to

junction possibly due to an anisotropic

gap function. The I-V curves show the

peculiar square law dependence of the

current on voltage seen in many

tunneling measurements of polycrystalline samples of 90-K superconductors.

This may be an indication of an inherent

"granularity" built into the supercon-
CEEE Technical Progress Bulletin - July 1988 Page 19

Superconductors (cont'd.)

ducting matrix of a single crystal.

[Contact: John Moreland, (303) 497-

3641]

Moreland, J., and Hirabayashi, H. , 18th

International Conference on Low

Temperature Physics (LT-18).

This note discusses results presented

relating to superconductivity, especially superconductivity above liquidnitrogen temperature at the 18th

International Conference on Low

Temperature Physics (LT-18), held in

Kyoto, Japan, August 20-26, 1987. Over

1600 persons from 36 countries attended

LT-18, with papers presented in areas

including superconductivity, magnetism,

heavy-electron systems, density waves,

thermometry, cryogenic techniques,

liquid helium 3 and helium 4 and

superfluid properties, critical

phenomena, polarized systems, metals,

and semiconductors . About 200 of the

contributed papers (20% of the total)

were on high-critical- temperature

superconductors, and there was a special

symposium on this topic.

[Contact: John Moreland, (303) 497-

3641]

Recently Published

Chen, D.-X, Goldfarb, R.B. , Nogues, J.,

and Rao, K.V. , Magnetic Susceptibility

of Sintered and Powdered Y-Ba-Cu-0

(Original title: Susceptibility

Measurements of a Sintered and Powdered

Y-Ba-Cu-0 Superconductor) , Journal of

Applied Physics, Vol. 63, No. 3, pp.

980-983 (1 February 1988).

The real and imaginary parts of magnetic

ac susceptibility of a sintered Y-BaCu-0 superconductor were measured as

functions of temperature. The susceptibility may be separated into two

contributions, one sensitive and the

other relatively insensitive to the

magnitude of the measuring field. The

former is partially suppressed upon

coarsely crushing the sample. It is

completely suppressed after finely

powdering, whereupon the susceptibility

curves become insensitive to the

magnitude of the measuring field.

Several models might be consistent with

the results.

[Contact: Ronald B. Goldfarb, (303)

497-3650]

Ekin, J.W., Transverse Stress Effect on

Multifilamentary Nl^Sn Superconductor,

Advances in Cryogenic Engineering

Materials, Vol. 34, pp . 547-552 (Plenum

Publishing Corporation, 1988).

A large reversible degradation of the

critical current of multifilamentary

Nb 3 Sn superconductors has been observed

under application of uniaxial compressive stress at 4 K applied transverse to

the conductor axis. In bronze-process

multifilamentary Nb 3 Sn, the onset of

significant degradation occurs at about

50 MPa. The intrinsic effect of

transverse stress on the upper critical

field is about ten times greater than

for axial stress. Although transverse

stress on the Nb 3 Sn filaments is less

than axial stress, it will need to be

considered in the internal stress

design of large magnets. The effect

scales with conductor thickness and

consequently will place limits on

conductor dimensions and the spacing

between distributed reinforcement in

large magnets.

[Contact: John W. Ekin, (303) 497-

5448]

Goodrich, L.F., Bray, S.L., and Clark,

A.F., Current-Ripple Effect on

Superconductive DC Critical Current

Measurements, Advances in Cryogenic

Engineering Materials, Vol. 34, pp

.

1019-1026 (1988).

The effect of sample current power

supply ripple on the measurement of dc

critical current is reported. Measurements were made on multifilamentary NbTi

superconductors. Ripple in a current

supply becomes more significant above

500 A because effective filtering

becomes more difficult. The presence of
Page 20 CEEE Technical Progress Bulletin - July 1988

Superconductors (cont'd.)

current ripple reduces the measured dc

critical current. Ripple can also

directly affect the voltmeter used for

the measurements , because it has to

operate with a noisy input. The

quantitative effect of current ripple

was studied using a battery current

supply instrumented to allow the

creation of ripple current with variable

frequency and amplitude. Problems

common to all large conductor critical

current measurements are discussed.

[Contact: Loren F. Goodrich, (303) 497-

3143]

Moreland, J.M., Ekin, J.W., Goodrich,

L.F., Capobianco, T.E., and Clark,

A.F., Electron Tunneling Measurements

in LaSrCuO and YBaCuO, Proceedings of

Symposium S, 1987 Spring Meeting of the

Materials Research Society, Anaheim,

California, April 23-24, 1987, pp . 273-

275 (1988).

The break junction technique whereby

vacuum tunneling occurs within the

fracture of a bulk sample is used to

study the LaSrCuO and YBaCuO perovskite

superconductors. Structure in the

current -versus -voltage characteristics

is reminiscent of previous quasiparticle

curves obtained for BCS superconducting

materials . Some curves have anomalous

qualities, including large dips in the

junction conductance with increasing

voltage just above a well-defined

tunneling gap edge, linearly increasing

junction conductance with applied bias,

along with features occurring near

voltage intervals following a 1, 3, 5

pattern.

[Contact: John M. Moreland, (303) 497-

3641]

Moreland, J.M., Goodrich, L.F., Ekin,

J.W., Capobianco, T.E. , and Clark,

A.F., Anomalous Behavior of Tunneling

Contacts in Superconducting Perovskite

Structures, Advances in Cryogenic

Engineering Materials, Voi. 34, pp.

625-632 (Plenum Publishing Corporation,

1988)

Our break junction results for electron

tunneling spectroscopy of the perovskite

superconductors La-Sr-Cu-0 and Y-Ba-Cu-0

are similar to those obtained using

thin- film, scanning tunneling microscopy, and point- contact methods.

Energy gap structures are sometimes

observed in the measured current-voltage

characteristics. More often, however,

the characteristics are anomalous when

compared to previous tunneling studies

of BCS superconductors. The anomalies

include linearly increasing conductance

with voltage, large deviations in

junction conductance above the gap edge,

and junction diode action. We discuss

some possible explanations for these

observations

[Contact: John M. Moreland, (303) 497-

3641]

Other Electrical Systems Topics

Released for Publication

Martzloff , F.D. , A Review of Candidate

Methods for Detecting Incipient Defects

Due to Aging of Installed Cables in

Nuclear Power Plants, to be published

in the Proceedings of the Workshop on

Power Plant Cable Condition Monitoring,

San Francisco, California, February 16-

18, 1988; and as NBSIR 88-3791.

Several types of test methods have been

proposed for detecting incipient

defects due to aging in cable insulation

systems, none offering certainty of

detecting ail possible types of defects.

Some methods apply direct detection of a

defect in the cable; other methods

detect changes in electrical or

nonelectrical parameters from which

inferences can be drawn on the integrity

of the cable. The paper summarizes the

first year of a program conducted at

the National Bureau of Standards to

assess the potential of success for insitu detection of incipient defects by

these methods.

[Contact: Francois D. Martzloff, (301)

975-2409]
CEEE Technical Progress Bulletin - July 1988 Page 21

ELECTRQMAGMETIC INTERFERENCE

Radiated Electromagnetic Interference

Released for Publication

Came 11 s D.G. , Larsen, E.B. , and Anson,

W.J., MBS Calibration Procedures for

Horizontal Dipole Antennas (25 to 1000

MHz), to be published in the Symposium

Record of the 1988 IEEE International

Symposium on Electromagnetic Compatibility, Seattle, Washington, August

2-4, 1988.

The theoretical basis and test procedures for horizontally polarized dipole

calibrations at the National Bureau of

Standards are described. Two different

techniques and two different test sites

are used for these measurements . The

standard antenna method uses the

calculation of a field strength level,

from the response of a simple half-wave

dipole, to calibrate an antenna. This

method is used at an open-field site in

the frequency range 25 to 1000 MHz. The

standard field method applies the

theoretical gain equations of waveguides

to determine the field strength level.

This latter method is used in an

anechoic chamber in the frequency range

200 to 1000 MHz. Procedures for both

techniques are explained and measurement

setups are illustrated. Measurement

uncertainties are discussed.

[Contact: Dennis G. Caraell, (303) 497-

3214]

Driver, L.D. , and Kanda, M. , An

Optically Linked Electric and Magnetic

Field Sensor for Poynting Vector

Measurements in the Near Fields of

Radiating Sources.

A unique, single-element antenna -sensing

scheme is described which can simultaneously measure the electric,

magnetic, and time -dependent Poynting

vectors of electromagnetic (EM) fields.

The electric and magnetic responses of

the antenna sensor are separated by a

0°/180° hybrid junction. The resulting

two radio -frequency voltages, along with

relative phase and frequency information, are transmitted to a remotely

located vector analyzer by a pair of

well-matched fiber optic downlinks. The

remote receiver displays: (1) the

electric dipole response, (2) the

magnetic loop response, and (3) the time

phase difference between the two. This

information is sufficient to determine

the time -dependent Poynting vector.

Both a theoretical analysis and a discussion of the experimental measurements performed are presented, which

describe the capabilities and performance of a working prototype of the

antenna measurement scheme . The

results demonstrate that a three -axis

(isotropic) version of this system could

be used to measure the near- fields of EM

sources, as well as to completely

describe the resultant flow of energy.

[Contact: Lanny D. Driver, (303) 497-

3911]

Kanda, M. , and Driver, L.D. , An

Optically Linked Electric and Magnetic

Field Sensor for Poynting Vector

Measurements in the Near Field of

Radiating Sources

.

An improved, single -element antennasensing technique is described which can

simultaneously measure the electric (E)

field, magnetic (H) field, and timedependent Poynting vector of electromagnetic (EM) fields. Two radio -frequency

voltages are produced which, along with

relative phase and frequency information, are transmitted to a remotely

located vector analyzer by a pair of

matched fiber optic downlinks.

[Contact: Motohisa Kanda, (303) 497-

5320]

Ma, M.T., Theory and Measurements of

Unintentional Radiators

.

By characterizing an unknown emitter

with equivalent vector electric- and

magnetic-dipole moments, we formulate a

theoretical basis to express the

radiation properties of such an emitter

in terms of these unknown dipole

moments. Power and relative phase
Page 22

Radiated EMI (cont'd.)

CEEE Technical Progress Bulletin - July 1988

measurements from appropriate ports of a

transverse electromagnetic cell, when

the emitter is placed at the cell's

center, are proven to be sufficient to

determine quantitatively the unknowns

and, therefore, the radiation characteristics . [Contact: Mark T. Ma, (303) 497-3800]

Randa, J.P., Kanda, M. , Melquist, D.G.,

Sega, R.M.

and Norgard, J.D., High

Frequency Electrie -Fie Id Probe Development, to be published in the Proceedings of the EMC EXPO' 88 Conference,

Washington, D.C., May 10-12, 1988.

Various designs have been considered for

electric-field probes for the frequency

range 26 to 110 GHz. A fiber optic

temperature sensor to detect the heating

of a resistive strip was designed,

built, and tested. With increased

sensitivity, this design may be capable

of operating to above 100 GHz.

[Contact: James P. Randa, (303) 497-

3150]

Reeve, G.R., Proficiency Testing for

MIL-STD 462 NVLAP Laboratories, to be

published in the Proceedings of the EMC

EXPO' 88 Conference, Washington, D.C.,

May 10-12, 1988.

Some of the difficulties in obtaining

accurate results using MIL-STD 462 test

procedures are reviewed. Several

measuring standard devices whose

characteristics have been determined

accurately are presented that could be

used for verification of test results

along with their application to

proficiency testing for NVLAP certification.

[Contact: Gerome R. Reeve, (303) 497-

3557]

Vanzura, E.J., Automated System for

Electromagnetic Field Generation and

Immunity Testing, to be published in

the 1988 IEEE Instrumentation/

Measurement Technology Conference, San

Diego, California, April 19-22, 1988.

An interactive computer-controlled

system has been constructed for radiated

immunity measurements. It can set up a

desired unperturbed field strength at a

point in space and simultaneously

measure field strengths and polarizations at up to ten different positions.

Field mapping experiments have been

performed with the system in an anechoic

chamber, a partially loaded shielded

room, and an unloaded shielded room.

Results confirm dramatic improvement in

spatial field uniformity as more

absorber is used. If the unperturbed

fields in a specified test volume do not

deviate more than a desired amount for

any frequency of interest, meaningful

immunity tests can be performed. An

equipment under test (EUT) is placed

into the test volume and its response to

radiation is measured using current

probes and a spectrum analyzer. Such an

experiment requires many mid- experiment

calculations , making automation highly

desirable because of significant time

savings

Our frequency range of interest is 50 to

200 MHz because this is a particularly

difficult frequency band in which to

perform reliable immunity tests. By

measuring the field variations in a test

zone, systematic uncertainty limits due

to spatial field deviations can be

estimated more accurately. This allows

testing in an anechoic chamber below

what is normally considered its lowest

usable frequency. If an anechoic

chamber is not available, a partially

loaded shielded room can be used, with

the necessary requirement that specifications on spatial field uniformity be

relaxed.

This measurement system can be used in

conjunction with many other facilities,

such as a tranverse electromagnetic

cell, an open-field site (ground screen)

or a reverberating chamber, and can be

used to test at frequencies from the low

kilohertz up to 2 GHz.

[Contact: Eric J. Vanzura, (303) 497-

5752]
CEEE Technical Progress Bulletin - July 1988 Pape 23

Radiated EMI (cont'd.)

Wilson, P.F., and Ma, M.T., Techniques

for Measuring the Electromagnetic

Shielding Effectiveness of Materials

Part II -- Near-Field Source Simulation.

Shielding effectiveness relates to the

ability of a material to reduce the

transmission of propagating fields in

order to electromagnetically isolate one

region from another. Because the

shielding capability of a complex

material is difficult to predict, it

often must be measured. Two measurement

approaches based on near- field source

simulation are studied, namely, the use

of the dual TEM cell and an apertured

TEM cell in a reverberating chamber. In

each case, we consider the system

frequency range, test sample requirements, test field type, dynamic range,

measurement time required, analytical

background, and present data taken on a

common set of materials

.

[Contact: Mark T. Ma, (303) 497-3800]

Wilson, P.F., Ma, M.T. , and Adams , J.W.,

Techniques for Measuring the Electromagnetic Shielding Effectiveness of

Materials: Part I -- Far-Field Source

Simulation.

Shielding effectiveness relates to the

ability of a material to reduce the

transmission of propagating fields in

order to electromagnetically isolate one

region from another. Because the

shielding capability of a complex

material is difficult to predict, it

often must be measured. A number of

far-field source simulation measurement

approaches are studied, including the

use of coaxial transmission- line

holders and a time-domain system. In

each case, we consider the system

frequency range, test sample requirements, test field type, dynamic range,

measurement time required, analytical

background, and present data taken on a

common set of materials.

[Contact: Mark T. Ma, (303) 497-3800]

Wilson, P.F., Ondrejka, A.R. , and Ma,

M.T. , ESD Radiated Electromagnetic

Fields -- Theory and Experiment, to be

published in the Symposium Record of

the 1988 IEEE International Symposium

on Electromagnetic Compatibility,

Seattle, Washington, August 2-4, 1988.

Electrostatic discharge (ESD) can be a

serious threat to electronic equipment.

To date, metrology efforts have focused

primarily on ESD-associated currents in

order to develop test simulators.

Significantly less work has been done on

the ESD-radiated fields. This paper

examines the fields problem, both

theoretically and experimentally.

Measurements indicate that the electric

fields can be quite significant (>150

V/m at a distance of 1.5 m) , particularly for relatively low-voltage sparks (<6

kV) . A theoretical dipole model for the

ESD spark is developed to compute the

radiated fields if the required current

waveform can be modeled based on

measurements. The agreement between

theory and experiment is good. The

model may be used to predict the fields

for a wide range of possible discharge

configurations

.

[Contact: Mark T. Ma, (303) 497-3800]

Wu, D.I., and Chang, D.C., The Effect of

a Large Rotating Scatterer in a

Rectangular Cavity, to be published as

NBS Technical Note 1317.

In a mode-stirred chamber, the field in

the cavity is perturbed with a stirrer,

i.e., a rotating scatterer, in such a way that it is uniformly random. In

this report, we investigate the key

factor which governs the effectiveness

of a stirrer. By examining the

fundamental properties associated with a perturbing body in a cavity, we find

that the key to effective field

perturbation lies in the shifting of

eigenmode frequencies. When the size of

the perturbing body becomes large, the

shifting may be large enough that the

new perturbed modes no longer resemble

the original unperturbed modes . In

effect, as this body rotates, different
Page 24

Radiated SMI (cont'd.)

CEEE Technical Progress Bulletin - July 1988

perturbed modes may be excited, thus

introducing randomness into the system.

We illustrate this phenomenon by

examining a 2D cavity with a ID

perturbing body. Using the transmission-line-matrix method, the shifting of

eigenfrequencies and the variation on

the magnitude of the fields for

different stirrer sizes are computed.

From this analysis, useful insights are

drawn which include an analogy between

the action of a large stirrer and a

frequency modulator.

[Contact: Doris I. Wu, (303) 497-3214]

Wu, D.I., and Chang, D.C., A Hybrid

Representation of the Green's Function

in an Over-Moded Rectangular Cavity.

A hybrid ray-mode representation for the

Green's function in a rectangular

cavity is developed using the finite

Poisson summation formula. In order to

obtain a numerically efficient scheme

for computing the field generated by a

point source in a large rectangular

cavity, the conventional modal representation of the Green's function is

modified in such a way that all the

modes near resonance are retained, while

the truncated remainder of the mode

series is expressed in terms of a

weighted contribution of rays. For a

large cavity, the contribution of rays

from far-away images becomes small;

therefore, the ray sum can be approximated by one or two dominant terms

without a loss of numerical accuracy.

To illustrate the accuracy and the

computational simplification of this

ray-mode representation, numerical

examples are included with conventional

mode series (summed at the expense of

long computation time) serving as a

reference

[Contact: Doris I. Wu, (303) 497-3842]

Recently Published

Adams, J.W., Ondrejka, A.R.

and Medley,

H.W. , Time-Domain System for Identification of the Natural Resonant

Frequencies of Aircraft Relevant to

Electromagnetic Compatibility Testing,

NBSIR 87-3077 (November 1987).

A method for measuring the natural

resonant frequencies of a structure is

described. The measurement involves

radiating an aircraft with an impulsive

electromagnetic field and receiving the

echo reflected from this aircraft.

Resonances are identified by using a

mathematical algorithm based on Prony's

method to operate on the digitized

reflected signal. The measurement

system consists of special transverse

electromagnetic horns, pulse generators,

a time-domain system, and an implementation of Prony's algorithm. The

frequency range covered is 5 to 250

MHz; this range is determined by antenna

and circuit characteristics.

The use of this system is shown, and

measured data from several different

helicopters are presented in different

forms. These different forms are needed

to determine which of the resonant

frequencies are real and which are

false. The false frequencies are

byproducts of Prony's algorithm.

[Contact: John W. Adams, (303) 497-

3328]

Cavcey, K.H.and Friday, D.S., Aircraft

Field Degradation and Electromagnetic

Compatibility, NBSIR 88-3083 (January

1988) .

This paper discusses the first tests

undertaken to study the problem of field

degradation in army aircraft (helicopters and one fixed-wing airplane) due to

the deterioration of electronic and

electrical systems. The electromagnetic

compatibility of such systems was

investigated by passive measurement of

each aircraft as a collection of radiofrequency sources. Methods for

detection of these sources were

developed that included sensitivity to

both stationary and nonstationary noise

that existed.

The collected data were studied to see
CEEE Technical Progress Bulletin - July 1988 Page 25

Radiated EMI (cont'd.)

if there existed any obvious factors

derived from the data that one could use

to correct potential problems that

might affect flight safety. Emphasis

was placed upon making such test methods

appropriate, inexpensive, and easily

performed by army field personnel. In

addition, applications to quality

control or acceptance testing, as

related to the Environmental Stress

Screening program, were examined.

[Contact: Kenneth H. Cavcey, (303) 497-

3995]

Crawford, M.L., Koepke , G.H., and

Ladbury, J.M., EMR Test Facilities,

Evaluation of Reverberating Chamber

Located at RADC, Griffiss AFB, Rome,

New York, NBSIR 87-3080 (December

1987).

This report describes measurement

procedures and results obtained from

evaluating the reverberating chamber

facility located at the Rome Air

Development Center (RADC) , Griffiss Air

Force Base, Rome, New York. The

facility was developed by the RADC for

use in measuring and analyzing the

electromagnetic susceptibility/

vulnerability of weapon systems and the

shielding effectiveness of enclosures

and shielding materials. A brief

description of the facility, including

the instrumentation used for performing

its evaluation and calibration by the

National Bureau of Standards, is given.

Measurements described include: (1)

evaluation of the chamber's transmitting

and receiving antennas' voltage

standing-wave ratios; (2) measurement of

the chamber's insertion loss or coupling

efficiency versus frequency; (3)

measurement of the chamber's tuner

effectiveness; (4) determination of the

electric- (E-) field uniformity in the

chamber's test zones versus frequency;

(5) determination of the absolute

amplitude calibration of the test Efields in the chamber based upon the

reference antenna's received power

measurements and calibrated dipole probe

antenna measurements; (6) comparison of

reference standard equipment under test

responses to test fields established

inside the RADC reverberating chamber

and the NBS anechoic chamber; and (7)

evaluation of the performance

characteristics of the reverberating

chamber excited by pulsed radio

frequency (rf) at selected discrete

frequencies as a function of pulse width

(0.2 to 20 /is) and the chamber's quality

factor (Q) . Conclusions indicate that

the chamber can be used at frequencies

down to approximately 150 MHz for

continuous -wave (cw) testing, and for rf

pulsed immunity testing with pulse

widths as short as 0.3 f.is by using rf

absorber loading. Immunity testing to

pulsed rf fields, however, has some

inherent limitations that are discussed

in the report. Estimates of the cw

measurement uncertainties derived

empirically from the test results are

given.

[Contact: Myron L. Crawford, (303) 497-

5497]

Randa, J., Kanda, M. , and Melquist, D. , Possible Designs for Electric-FieldStrength Probes for Millimeter Waves,

NBSIR 88-3084 (February 1988).

Various designs are considered for

electric-field probes for the frequency

range from 26 to 110 GHz. Two particular designs are investigated in

some detail. A resistively tapered

dipole antenna with a diode detector

shows promise for frequencies up to

about 40 GHz. The second design is

based on a fiber-optically sensed

temperature sensor to detect the heating

of a resistive strip. If its sensitivity can be increased significantly,

this design may be capable of operating

to frequencies above 100 GHz.

[Contact: James P. Randa, (303) 497-

3150]

Wilson, P.F., Ondrejka, A.R. , Ma, M.T.,

and Ladbury, J.M., Electromagnetic

Fields Radiated From Electrostatic

Discharges Theory and Experiment, NBS

Technical Note 1314 (February 1988)

.
Page 26

Radiated EMI ( cont ' d .

CEEE Technical Progress Bulletin - July 1988

The fields radiated by electrostatic

discharges (ESD) are studied both

theoretically and experimentally. The

ESD spark is modeled theoretically as

an electrically short, time - dependent

linear dipole situated above an infinite

ground plane. Experimentally, sparks of

varying voltages are generated by a

commercially available simulator and

used to excite a number of targets

including: (1) the extended inner

conductor of a coaxial cable mounted in

a ground plane, (2) direct discharges to

a ground plane, (3) indirect radiation

from a large metal plate, (4) a metal

chair over a ground plane, and (5) a

metal trash can. Results show that

relatively low-voltage sparks (2 kV to 4

kV) excite the strongest radiated

fields. This suggests that the spark

fields can pose a significant interference threat to electronic equipment

into the gigahertz range

[Contact: Mark T. Ma, (303) 497-3800]

Conducted Electromagnetic Interference

Recently Published

Martzloff , F.D. , Power Quality Measurements: Bringing Order Out of Chaos,

Energy Technology XV -- Repowering

America (Proceedings of the Energy

Technology Conference, Washington, DC,

February 17-19, 1988) (Government

Institutes, Inc., Maryland), pp . 947-

959.

The quality of the power supplied to

sensitive electronic equipment is an

important issue. Quantifying this

quality, however, is difficult under the

present state of nonexistent or

uncoordinated standards concerning two

related questions: (1) what levels of

power quality are required for what

types of loads, and (2) what measurement

techniques are required to determine

reliably the level of disturbances that

reduce quality. Development of

standards by the consensus process and

voluntary compliance, although a slow

process, is a mechanism for reaching

technically sound and cost-effective

solutions. Several standards projects

are in progress, but need industrywide support to become the generally

accepted basis for valid and useful

measurements of power quality.

[Contact: Francois D. Martzloff, (301)

975-2409]

ADDITIONAL INFORMATION

Lists of Publications

Gibson, K.A.Page, J.M., and Miller,

C.K.S., A Bibliography of the NBS

Electromagnetic Fields Division

Publications, NBSIR 85-3040 (February

1986)

This bibliography lists publications of

the National Bureau of Standards'

Electromagnetic Fields Division for the

period from January 1984 through

September 1985, with selected earlier

publications from the Division's

predecessor organizations.

[Contact: Kathryn A. Gibson, (303) 497-

3132]

Kline, K.E., and DeWeese, M.E.,

Metrology for Electromagnetic Technology: A Bibliography of NBS Publications, NBSIR 87-3074 (June 1987).

This bibliography lists the publications

of the personnel of the Electromagnetic

Technology Division of NBS in the period

from January 1970 through December 1986.

A few earlier references that are

directly related to the present work of

the Division are included.

[Contact: Sarabeth Moynihan, (303) 497-

3678]

Palla, J.C., and Meiselman, B. , Electrical and Electronic Metrology: A

Bibliography of NBS Electrosystems

Division Publications, NBS list of

Publications 94 (January 1988)

This bibliography covers publications of

the Electrosystems Division, Center for

Electronics and Electrical Engineering,
CEEE Technical Progress Bulletin - July 1988 Page 27

Lists of Publications (cont'd.)

NBS, and of its predecessor sections for

the period January 1963 to January 1988.

A brief description of the Division's

technical program is given in the

introduction.

[Contact: Jenny C. Palla, (301) 975-

2220 ]

Walters, E.J., Semiconductor Measurement

Technology, NBS List of Publications 72

[a bibliography of NBS publications

concerning semiconductor measurement

technology for the years 1962-1987]

(March 1988)

.

This bibliography contains reports of

work performed at the National Bureau of

Standards in the field of Semiconductor

Measurement Technology in the period

from 1962 through December 1987. An

index by topic area and a list of

authors are provided.

[Contact: E. Jane Walters, (301) 975-

2050]

RECENTLY ISSUED

STANDARD REFERENCE MATERIALS

The Semiconductor Electronics Division

announces the release of a new Standard

Reference Material (SRM) for ellipsometrically derived thickness and

refractive index of a silicon dioxide

film on silicon. Available for sale to

the public through the NBS Office of

Standard Reference Materials [for

orders, (301) 975-6776], SRM 2530 is

separately available for three oxide

thicknesses: 50 nm (2530-1), 100 nm

(2530-2), and 200 nm (2530-3).

This SRM was developed to respond to

industry needs to evaluate the accuracy

of ellipsometers , but may also be used

as aid in the calibration of various

other optical and mechanical thickness

monitoring instruments.

Each SRM consists of a 76-mm (3-in.)

diameter silicon wafer on which a

uniform silicon dioxide layer was grown,

patterned, and partially covered with

chromium. The certified values were

determined from measurements made using

the highly accurate ellipsometer

developed in the Division and are the

ellipsometric parameters delta, A, and

psi, ip, at a wavelength of A = 632.8 nm.

The SRMs are also certified for the

derived values of thickness and

refractive index of its silicon dioxide

layer determined by using a two -layer

model consisting of a silicon dioxide

layer on a thin silicon-rich oxide

interlayer. [Contact: George A.

Candela, (301) 975-2086]

1988 CEEE Calendar

August 23-26 (Vail, CO)

Laser Measurements Short Course. This

course will emphasize the concepts,

techniques, and apparatus used in

measuring laser parameters and will

incorporate a visit to the NBS laser

measurement laboratories. Attendees

will be assumed to have knowledge

equivalent to a degree in physics or

electrical engineering; some experience

in the use of lasers is desirable.

Major topic areas include: optics for

laser measurements, attenuation

techniques, laser operation, basic laser

power/energy standards, laser power-

/energy measurement techniques , pulse

measurements, transfer standards, beamprofile measurements, diode lasers,

laser measurements for optical communications, statistics and error

analyses, and laser safety. Instructors

will be drawn from NBS, industry, and

other government agencies. [Contact:

Office of Conference Services, (303)

492-5151; for technical information,

Douglas L. Franzen, (303) 497-3346]

September 12-14, 1988 (San Jose, CA)

VLSI and GaAs Chip Packaging Workshop.

This Workshop is co-sponsored by the

Components, Hybrids, and Manufacturing

Technology Society of IEEE and NBS;

attendees are expected to be knowledgeable in the field and to participate in
Page 28

CEEE Events (cont'd.)

CEEE Technical Progress Bulletin - July 1988

discussions. Topic areas include: VLSI

and wafer- scale package design (characterization and implementation, cost and

performance -driven solutions) ; package

thermal design (characteristics,

results, and issues); package interconnection options (wire bonding, TAB, flip

chip, or optical); GaAs IC packaging

(high-speed packaging considerations)

package electrical issues (reduction of

parasitics, improvements in electrical

performance, reduction in line resistance) ; integrating package design

(from die to system, including assembly

and test issues) ; VLSI package materials

advancements; die-attach solutions for

large chips; and new failure mechanisms

in VLSI packaging. [Contact: George G.

Harman, (301) 975-2097]

September 20-21, 1988 (Boulder, CO)

Symposium on Optical Fiber Measurements.

This symposium is intended to provide a

forum for the lightwave communications

community to discuss and possibly

resolve measurement problems related to

optical fiber, sources, detectors,

switches, couplers, modulators, and

other components. The symposium is

sponsored by NBS , in cooperation with

the Institute of Electrical and

Electronics Engineers' Optical Communications Committee, and the Optical

Society of America. Eight technical

sessions are scheduled, including

presentations relating to optical timedomain ref lectometry return loss,

polarization, losses, transmission

modes, cut-off wavelength, geometry, and

refractive index. [Contact: Douglas L.

Franzen, (303) 497-3346]

October 26-28, 1988 (Boulder, CO)

Twentieth Symposium on Optical Materials

for High Power Lasers (Boulder Damage

Symposium). In addition to the NBS,

this symposium is sponsored by the

American Society for Testing and

Materials, the Air Force Office of

Scientific Research, the Office of Naval

Research, the Defense Advanced Research

Projects Agency, and the Department of

Energy. It serves as the principal

forum for the exchange of information on

the physics and technology of materials

for high-power lasers. Topics to be

discussed include new materials, bulk

damage phenomena, surface and thin- film

damage, design considerations for highpower systems, and fundamental mechanisms of laser- induced damage.

[Contact: Aaron A. Sanders, (303) 497-

5341]

February 7-9, 1989 (San Diego, CA)

IEEE Semiconductor Thermal and Temperature Measurements Symposium. This

fifth annual SEMI-THERM symposium is

sponsored by the Components, Hybrids,

and Manufacturing Technology Society of

IEEE in cooperation with NBS and

constitutes an international forum for

the presentation of new developments

relating to generation and removal of

heat within semiconductor devices,

measurement of device temperatures, and

the simulation of device and system

thermal behavior. Major SEMI -THERM

topic areas include: thermal measurements; simulation, computation, and

software; thermal characterization; and

applications

The program includes keynote speakers,

technical presentations, tutorial

sessions, workshops, and an exhibit. In

addition, the Semiconductor Equipment

and Materials Institute (SEMI) and the

Joint Electron Devices Engineering

Council (JEDEC) have scheduled in

conjunction with SEMI -THERM several

Standards Committee Task Force meetings,

to which attendees are invited.

[Contact: Frank F. Oettinger, (301)

975-2054]

September 11-13, 1989 (Munich, FDR)

VLSI and GaAs Chip Packaging Workshop.

[Contact: George G. Harman, (301) 975-

2097]

December 7-8, 1989 (Gaithersburg, MD)
CEEE Technical Progress Bulletin - July 1988 Page 29

CEEE Events (cont'd.)

Power Semiconductor Devices Workshop.

[Contact: David L. Blackburn, (301)

975-2068]

CEEE SPONSORS

National Bureau of Standards

U.S. Air Force

Newark Air Force Station; Rome Air

Development Center; Space & Missile

Organization; U.S. Air Force

Headquarters; Wright- Patterson AFB;

Technical Applications Center; Kirtland

AFB; Cryptological Support Center

U.S. Army

Fort Belvoir; Fort Monmouth; Fort

Huachuca; Harry Diamond Laboratory;

Materials & Mechanics Research Center;

Redstone Arsenal; Strategic Defense

Command; AVRADCOM (Aviation)

Department of Commerce

Patent and Trademark Office

Department of Defense

Defense Nuclear Agency; Defense

Advanced Research Projects Agency;

National Security Agency; Combined

Army/Navy/Air Force Calibration

Coordination Group

Department of Energy

Energy Systems Research; Fusion

Energy; High Energy & Nuclear Physics;

Bonneville Power Administration

Department of Justice

Law Enforcement Assistance

Administration

U.S. Navy

Naval Ocean Systems Center; Weapons

Support Center/Crane; Office of Naval

Research; Naval Sea Systems Command;

Naval Postgraduate School; Naval Ship

Research Development Center; Naval Air

Systems Command; Naval Research

Laboratory; Aviation Logistics

Center/Patuxent; Naval Explosive

Ordnance

National Aeronautics & Space

Administration

Goddard Space Flight Center; Lewis

Research Center

Nuclear Regulatory Commission

Department of Transportation

National Highway Traffic Safety

Administration

Sandia National Laboratories
'
NBS-1 14A (REV. 2-80

U.S. DEPT. OF COMM.

4.

BIBLIOGRAPHIC DATA

SHEET (See in struction s)

1. PUBLICATION OR

REPORT NO.

NBSIR 88-3815

2 . Performing Organ. Report No. 3.

TITLE AND SUBTITLE

Publication Date

July 1988

Center for Electronics and Electrical Engineering Technical Progress Bulletin

Covering Center Programs, January to March 1988, with 1988 CEEE Events Calendar

5. AUTHOR(S)

E. Jane Walters, compiler

6. PERFORMING ORGANIZATION (If joint or other than N BS, see instructions) 7. Contract/Grant No.

NATIONAL BUREAU OF STANDARDS

U.S. DEPARTMENT OF COMMERCE

GAITHERSBURG, MD 20899

8 . Type of Report & Period Covered

January-March 1988

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City, State, ZIP)

10. SUPPLEMENTARY NOTES

All technical information included in this document has been approved for publication

previously.

J Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. I f document includes a significant

bi bl iography or literature survey, mention it here)

This is the twenty-second issue of a quarterly publication providing information on

the technical work of the National Bureau of Standards Center for Electronics and

Electrical Engineering. This issue of the CEEE Technical Progress Bulletin covers

the first quarter of calendar year 1988. Abstracts are provided by technical area

for both published papers and papers approved by NBS for publication.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolons)

antennas; electrical engineering; electrical power; electromagnetic interference;

electronics; instrumentation; laser; magnetics; microwave; optical fibers; semiconductors; superconductors

13. AVAILABILITY

m Unlimited

| | For Official Distribution. Do Not Release to NTIS

| | Order From Superintendent of Documents, U-.S. Government Printing Office, Washington, D.C.

20402.

[IT] Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

33

15. Price

$11.95

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