bluuebunny/crossref_metadata_2025_split huggingface dataset:
An unified theory of electromagnetic missiles generated by an arbitrary plane current source
Authors: Geyi Wen , Chengli Ruan , Weigan Lin 
Published: July 2007

AbstractIn this article a generalized study of electromagnetic (EM) missiles has been presented. An EM missile source condition has been derived from an arbitrary plane current distribution, and our analysis shows that an arbitrary plane current distribution of finite size has the ability to launch an EM missile, i.e., to realize slow decrease of energy, on any axis perpendicular to the source plane so long as the axis has an intersection point with the source region. This important result reveals that the EM missiles are very much like light beams which do not diverge. © 1992 John Wiley & Sons, Inc.
Improved born inversion for frequency‐swept microwave imaging of dielectric cylinder
Authors: Kim Sang‐Gi , Suh Kyoung‐Whoan , Ra Jung‐Woong 
Published: July 2007

AbstractAn improved Born inversion for microwave imaging of lossless dielectric cylinder is suggested. It extends the validity of the first‐order Born approximation for the reconstruction about 10 times in the multiplication of the size of the object and the square root of the relative dielectric constant minus one. The reconstructed image using the conventional Born and the improved Born are compared and shown. © 1992 John Wiley & Sons, Inc.
Modulated‐impurity‐concentration transferred‐electron devices exhibiting large harmonic frequency content
Authors: Jones Stephen H. , Tait Gregory B. , Shur Michael 
Published: July 2007

AbstractWe report large increases in the harmonic components of the oscillation current waveforms for InP and GaAs TEDs by appropriate modulation of the device doping profile. The results are based on accurate drift‐diffusion simulations of Gunn‐diode structures. An unoptimized InP modulated‐impurity‐concentration transferred‐electron device demonstrated a 100% increase in second‐harmonic power generation as compared with its companion TED. © 1992 John Wiley & Sons, Inc.
A novel direct‐detection optical transmission system based on polarization modulation
Authors: Betti S. , de Marchis G. , Iannone E. 
Published: July 2007

AbstractIn this article a novel polarization‐modulated direct‐detection (PM‐DD) system is presented. The compatibility of the proposed system with an IM‐DD‐based optical network using doped fiber optical amplifiers and the possibility to implement efficient multilevel modulation make it promising for application in the future telecommunication environment. © 1992 John Wiley & Sons, Inc.
Bandwidth extension for six‐port reflectometers via a simple numerical method
Authors: Colef Gabriel 
Published: July 2007

AbstractA simple numerical method for extension of the bandwidth of six‐port reflectometers is proposed. The bandwidth extension is accomplished through calculations and not by six‐port design improvements. The method is tested on a microstrip integrated six‐port reflectometer and results for different loads are presented. © 1992 John Wiley & Sons, Inc.
X‐band mmic voltage‐controlled oscillator using HEMTS
Authors: Allamando Etienne André 
Published: July 2007

AbstractAn alternative approach for the design of a voltage‐controlled oscillator is proposed. It consists of using an appropriate field effect transistor which exhibits height value of constant transconductance and a high slope of gate capacitance. An MMIC realization using HEMTs is presented with experimental results obtained in X‐band. A minimum output power of 17 mW with a voltage tunable over a 17 percent bandwidth centered at 10.2 GHz is obtained. © 1992 John Wiley & Sons, Inc.
Millimeter‐wave injected‐lock frequency dividers
Authors: Rushan Chen , Minsong Sun , Xingguo Li 
Published: July 2007

AbstractIn this article the theoretical and experimental performances of a TED harmonically synchronized frequency divider are presented. The results show that such a divider has a 35.1–11.7‐GHz division, with 25‐mW output power over the operating band greater than 1000 MHz at 50‐mW input power level. © 1992 John Wiley & Sons, Inc.
Alloy ramp heterostructure diodes for microwave mixer applications
Authors: Tait Gregory B. 
Published: July 2007

AbstractSimulated and experimental data on mixer performance of semiconductor alloy ramp heterostructure diodes are presented. The results indicate that these devices are excellent candidates for use in microwave and millimeter‐wave mixer circuits. In addition, they possess several significant advantages over contending Schottky barrier diodes, the microwave industry workhorse for mixers and detectors. © 1992 John Wiley & Sons, Inc.
New coplanar waveguide feed network for 2 × 2 linearly tapered slot antenna subarray
Authors: Simons Rainee N. , Perl Thomas D. , Lee Richard Q. 
Published: July 2007

AbstractA new technique for exciting 2 × 2 subarray of linearly tapered slot antennas (LTSAs) with coplanar waveguide (CPW) is presented. rf power is coupled to each element through a CPW‐to‐slotline transition by a coax‐to‐CPW in‐phase four‐way radial power divider. The transition and the power divider are coupled by a novel nonplanar CPW right‐angle bend. Measured results at 18 GHz show excellent radiation patterns and return‐loss characteristics. © 1992 John Wiley & Sons, Inc.
A new calibration method for the four‐port reflectometer
Authors: Hongxiong Wu , Daquan Liu , Chuhua Pan 
Published: July 2007

AbstractA new calibration method for the four‐port reflectometer is presented and has been applied at Ka band. Some experimental results are given. They show that the present method has a simple and rapid calibration procedure and has the same measurement accuracy as the one in [1]. © 1992 John Wiley & Sons, Inc.
Dual‐mode tunable semiconductor laser with a grating‐grating external cavity
Authors: Conforti Evandro 
Published: July 2007

AbstractA technique for continuous operation of a dual‐mode tunable laser with a compound grating‐grating external cavity is presented. Double‐wavelength operation is obtained. The two modes of the laser can be independently tuned to achieve mode spacing frequencies from 130 to 370 GHz. Possible ways to increase this range are also discussed. This technique may be useful for millimeter‐wave generation by optical mixing. © 1992 John Wiley & Sons, Inc.
Influence of if narrow‐band filtering on bit error rates in coherent optical heterodyne CPFSK receiver using variable delay demodulation
Authors: Zhang Xiupu , Jiang Peixuan 
Published: July 2007

AbstractIn this article we discuss a coherent optical heterodyne CPFSK receiver using optimum variable delay demodulation considering the effect of narrow‐band IF filtering or intersymbol interference (ISI) caused by it. First we investigate the error probability at the normalized bandwidth of IF filter BT = 1 for a Gaussian IF filter. Numerical results show that the impact of narrow‐band IF filtering increases with an increase in normalized IF spectral linewidth ΔvT and a decrease in modulation index h. Second, in order to decrease the impact of ISI, the optimum BT values are determined, which can minimize the error probability for given SNR. If a Gaussian IF filter is used, the optimal BT values are 1.3 for ΔvT = 0.25%, 1.4 for ΔvT = 0.5% at h = 0.5, 1.2 for ΔvT = 0.25%, 1.4 for ΔvT = 0.5% at h = 0.7, and 1.2 for all ΔvT ≤ 0.5% at h = 1. Finally, the performance of an optimal receiver employing optimum Gaussian IF filter is studied. We know that h = 1 is optimum and ΔvT ≤ 0.5% is necessary for 1‐dB EB/N0 penalty per bit at BER of 10−9. © 1992 John Wiley & Sons, Inc.
Experimental investigations into an electromagnetically coupled microstrip patch antenna
Authors: Karmakar N. C. , Bialkowski M. E. 
Published: July 2007

AbstractAn experimental investigation is carried out into the operation of an electromagnetically coupled (EMC) microstrip patch antenna consisting of double‐layer dielectrics with a microstrip feed line in between. The input impedance of the antenna is studied as a function of the patch width, the patch‐feed overlap, and the dielectric constants of two layers. © 1992 John Wiley & Sons, Inc.
A compact and stable acousto‐optical spectrometer
Authors: Garde M. J. , Sebastian J. L. , Pintado J. Martin , Gallego J. D. 
Published: July 2007

AbstractA compact (900 × 100 × 120 mm) acousto‐optical spectrometer (AOS) of 60‐MHz bandwidth and effective resolution of 100 kHz has been designed with a minimum number of components and simplicity as design criteria. The spectrometer allows for integration times of several minutes during source‐on and sky‐off phases. The TeO2 deflector does not use the usual tangent interaction outside the (110) axis, but a two‐band interaction known as quasitangent that leads to a greater bandwidth. The AOS is being used with the 14‐m antenna at the Centro Astronomico de Yebes facility, providing excellent results. © 1992 John Wiley & Sons, Inc.
Passive polarization splitter and crosstalk characteristics of Ti:LiNbO3 X switch
Authors: Wang Chi‐Yu , Tu Yuan‐Kuang 
Published: July 2007

AbstractIn simulation with the beam‐propagation method, we find that high Ti surface concentration in LiNbO3 will cause a great difference in crosstalk between the TE and TM mode of a laser beam when it propagates in the Ti:LiNbO3 × switch. This phenomena can be applied to design a passive integrated waveguide TE/TM polarization splitter with high splitting ratio, without using any electrode and applied voltage. © 1992 John Wiley & Sons, Inc.
Annealing effects on proton‐exchanged LiNbO3 optical waveguides using stearic acid
Authors: Pun E. Y. B. , Chung P. S. , Loi K. K. 
Published: July 2007

AbstractAnnealing of proton‐exchanged planar optical waveguides in z‐cut LiNbO3 fabricated using stearic acid has been studied systematically. The effects of annealing on waveguide propagation loss, surface index change, and waveguide depth were measured as a function of annealing time, and were found to follow a power‐law relationship. © 1992 John Wiley & Sons, Inc.
A modified least‐squares boundary residual method for the rigorous analysis of MICS
Authors: Essaaidi M. , Boussouis M. 
Published: July 2007

AbstractIn this article we present a modified least‐squares boundary residual (LSBR) method for the rigorous analysis of microwave integrated circuits (MICs). The method is relatively convergent and a semianalytical relative convergence criterion is found to be very important in optimizing its convergence. Moreover, the problem of the poor conditioning of the least‐squares matrices has been rigorously resolved. © 1992 John Wiley & Sons, Inc.
A novel method for measuring the aluminum concentration in AlxGa1−xAs alloy system
Authors: Chuang Wei‐Ching , Chang Wen‐Chung , Chen Jiahn‐Ann , Lee Wei‐Yu 
Published: July 2007

AbstractA simple method for obtaining optical transmission spectra of AlxGa1‐xAs epilayer by translucent AB wax is presented. Absorption spectra are measured for x in the range of 0 ≤ x ≤ 0.8. For the Γ15v‐Γ1C energy bandgap, the aluminum concentrations, calculated from the experimental data with a formula derived by the ray‐optics method, are in good agreement with those reported. © 1992 John Wiley & Sons, Inc.
Large‐signal microwave transistor modeling using multiharmonic load‐pull measurements
Authors: Hajji Rached , Ghannouchi Fadhel M. , Bosisio Renato G. 
Published: July 2007

AbstractThis article presents a method of transistor parameter extraction using multiharmonic Load‐Pull (MHLP) measurements completed with modified harmonic balance calculations. An advantage of this approach is that the parameters of the nonlinear elements of the transistor are obtained solely from large‐signal measurements at the fundamental and the generated harmonic frequencies. The calculated parameters of the nonlinear model of a commercial MESFET (NE 71083), are found suitable for large‐signal operating mode at different impedance loading. © 1992 John Wiley & Sons. Inc.
Special consideration on the design of a Y‐junction optical waveguide
Authors: Jeng Jyh‐Yuan , Wang Way‐Seen 
Published: July 2007

AbstractThe characteristic deterioration of a titanium indiffused Y junction due to the photolithographic process constraint is simulated. It is found that with a slight increase in propagation loss, an improved design, which uses a rounded angle instead of a sharp one for the fabrication of the Y junction, can be created. © 1992 John Wiley & Sons, Inc.
Rigorous analysis of a step discontinuity in a dielectric planar anisotropic waveguide
Authors: Topa António L. , Paiva Carlos R. , Barbosa Afonso M. 
Published: July 2007

AbstractUsing a discretizing procedure for the continuous spectral amplitude of the radiation modes and the least‐squares boundary residual method a rigorous analysis of a step discontinuity in a dielectric planar anisotropic waveguide is presented. The numerical examples clearly show the effect of the medium anisotropy on the scattering characteristics—namely on the radiation pattern—of a uniaxial dielectric step. © 1992 John Wiley & Sons, Inc.
A study on broad‐banding the tuning ratio for varactor‐tuned oscillators
Authors: Sinha M. P. 
Published: July 2007

AbstractAn analysis of varactor‐tuned oscillators (VTO) for bandwidth estimation is described. The advantage of using two varactors in a tuning circuit is discussed. It is shown that when VTO consists of two series‐tuning varactors, it is possible to broad‐band the tuning ratio by using a varactor in the feedback circuit © 1992 John Wiley & Sons, Inc.
Leakage characteristics of the cylindrical dielectric waveguide with a periodically varying radius
Authors: Kubo Hiroshi 
Published: July 2007

AbstractThe cylindrical dielectric waveguide with a periodically varying radius has been analyzed numerically. Leakage characteristics of the mode are investigated for the various waveguide parameters. It is shown that the direction of the radiative leakage can be adjusted by varying the periodicity. © 1992 John Wiley & Sons, Inc.
Microwave monolithic analogue frequency divider with GaAs HEMT
Authors: Bourdel E. , Delacressonniere B. , Gautier J. L. , Josse C. , Pouvil P. 
Published: July 2007

AbstractAn analogue frequency divider implemented with a new GaAs high electron mobility transistor (HEMT) MMIC technology is presented. This frequency divider is based on the frequency regeneration principle. The circuit operates in a frequency division bandwidth of 700 MHz at — I dBm incident input power level around 12.8 GHz. © 1992 John Wiley & Sons, Inc.
On the maximum numbers of independent adjustable parameters, peaks, and valleys in arbitrarily shaped linear array factor
Authors: Yu Cheng‐Cheh 
Published: July 2007

AbstractThe lines of reasoning on the maximum numbers of independent adjustable parameters, peaks, and valleys in an arbitrarily shaped linear factor are clearly stated and the corresponding characteristics table is also completely constructed in this article. The array factor may be either unsymmetrical or symmetrical, and with arbitrary odd or even number of exciting currents. So far as the author knows, this table appears for the first time in the open literature, and it is believed to be of much help to the designers of equispaced linear antenna arrays when numerically optimizing the differently specified peak and valley levels of the array factor by adjusting the available independent parameters related to the exciting currents in the element antennas. When the formulas tabulated in the array factor characteristics table are used to compare with the synthesized results using the well‐known numerical method for optimizing the synthesis of an arbitrary shaped array factor by Orchard, Elliott, and Stern [1] and Elliott [2], they show exact agreement. © 1992 John Wiley & Sons, Inc.
Frame synchronization of optical fiber dppm with dispersed pulse shapes
Authors: Elmirghani Jaafar , Cryan Robert , Clayton Mike 
Published: July 2007

AbstractOptical digital pulse position modulation (DPPM) is an effective modulation format for both free space and fiber communications. However, for the latter, system synchronization has not been considered. Here, we address this issue and present an original expression, supported by practical results, for evaluating the frame spectral properties of optical fiber DPPM. We use the established properties to optimize frame synchronization while using a dispersed DPPM pulse shape which is representative of optical fiber systems © 1992 John Wiley & Sons, Inc.
Application of a new simple method for the analysis of eccentric coaxial waveguides with a homogeneous dielectric
Authors: Odri P. , Marincic A. , Benson T. M. 
Published: July 2007

AbstractThe application of an adequate conformal mapping can considerably simplify the generation of the finite element mesh for some specific types of waveguides. Here we introduce a two‐step mapping to simplify the calculation of the propagation characteristics of an eccentric coaxial waveguide. © 1992 John Wiley & Sons, Inc.
The effect of optical intensity on the photoresponse of the GaAs mesfet
Authors: Paolella Arthur , Herczfeld Peter R. , Madjar Asher 
Published: July 2007

AbstractThis article is concerned with the effect optical intensity has on the frequency response, gain, and bandwidth of the GaAs MESFET when used as an optical detector. Measurements show that the photoresponse gain can be increased by 10 dB as the optical intensity is lowered, while the bandwidth of the MESFET can be increased by an order of magnitude with an increase in optical power. © 1993 John Wiley & sons, Inc.
Lightwave technology applied to microwaves in eastern europe
Authors: Berceli Tibor 
Published: July 2007

AbstractThe research and development results achieved in Eastern Europe in the field of lightwave‐microwave combined technology are reported. Optical control of FETs, amplifiers, and oscillators; microwave modulation of lasers; lightwave‐microwave phase detection, conversion, and synchronization; and optical control of phase‐locked oscillators are surveyed. Application possibilities in beam forming of phased arrays, multichannel TV transmission and personal communications networks are reviewed. © 1993 John Wiley & sons, Inc.
Accurate noise characterization of short gate length GaAs mesfets and hemts for use in low‐noise optical receivers
Authors: Greaves S. D. , Unwin R. T. 
Published: July 2007

AbstractAccurate noise characterization of MESFETs and HEMTs is required for the design of high‐frequency optical receivers. Here we consider a technique that extracts the intrinsic noise parameters P, R, C from measured noise data. Novel analytic expressions are presented as well as results that prove the validity of the technique. © 1993 John Wiley & sons, Inc.
An advanced GaAs monolithic transimpedance amplifier for high‐speed optical communication systems
Authors: Giannini F. , Paoloni C. , Orengo G. 
Published: July 2007

AbstractAn advanced design procedure for MMIC GaAs direct‐coupled transimpedance amplifier for gigabit/second‐rate optical communication systems is presented. A transimpedance gain of 67 dBω up to 2.5 GHz has been demonstrated. A complete set of simulated and measured results are presented to confirm the effectiveness of the design approach. The design and the realization have been performed within the framework of ESPRIT Project No. 5018 COSMIC. © 1993 John Wiley & sons, Inc.
Circuit model of low‐frequency transconductance and output resistance dispersion in ion‐implanted InP JFETs
Authors: Kruppa W. , Boos J. B. 
Published: July 2007

AbstractAn equivalent circuit which simulates the low‐frequency dispersion in the transconductance and the output resistance of an ion‐implanted InP JFET is presented. The dispersion consists of reductions in the transconductance and the output resistance occurring between 100 Hz and 1 MHz and involves two dominant time constants in each parameter. The equivalent circuit can be used for the design of monolithic fiber‐optic receiver preamplifiers and other small‐signal circuits. © 1993 John Wiley & sons, Inc.
New dual mode coupling using slotted dielectric resonator
Authors: Baillargeat D. , Verdeyme S. , Guillon P. , Guglielmi M. 
Published: July 2007

AbstractA new dual mode coupling technique for dual mode filters is presented. A slotted dielectric resonator, where notches take the place of the classical metallic coupling and tuning screws, is introduced. A theoretical analysis using the three‐dimensional finite‐element method permits rigorous prediction of the filter response. © 1993 John Wiley & sons, Inc.
ANALYTICAL BEHAVIOR OF THE SURFACE CHARGE DENSITY ON A CONDUCTOR WITH TWO CONSECUTIVE EDGES WITH RIGHT ANGLES
Authors: And Frank Olyslager , de Zutter Daniël 
Published: July 2007

AbstractWe study the singular behavior of the surface charge density at the corner of a thin perfect conductor with rectangular cross section taking into account the presence of a nearby corner. Analytical expressions by means of a Schwartz‐Christoffel transformation for the behavior of the surface charge density are obtained resulting from the interaction of both corners. This behavior is useful for the choice of basis functions in MoM techniques used to analyze strip lines and microstrips. © 1993 John Wiley & Sons, Inc.
Novel effects in wave reflection from biisotropic media
Authors: Sihvola Ari H. , Lindell Ismo V. 
Published: July 2007

AbstractThis report discusses the new effects and phenomena that can be discovered in wave reflection from a planar isotropic‐biisotropic interface. The reflection matrices and Brewster angles are used to derive the transmission dyadics of the problem and eigenpolarizations of the Brewster reflection condition. Nonreciprocal cross‐Brewster angles are derived for which one of the cross‐polarization reflection coefficients vanishes but not the other one. © 1993 John Wiley & Sons, Inc.
Modeling of Semibatch Esterification Process for Poly(ethylene terephthalate) Synthesis
Authors: Patel Himanshu , Feix Gunter , Schomäcker Reinhard 
Published: July 2007

AbstractThe esterification kinetics of terephthalic acid (TPA) and ethylene glycol (EG) in poly(ethylene terephthalate) (PET) synthesis were studied using a semibatch reactor. Rate constants were optimized by data fitting with the oligomeric chain length, the fraction of carboxyl groups in the terminal groups (α) and the water generation curve for different EG/TPA feed ratios. The influence of the TPA particle size distribution on the solid‐liquid mass transfer rate and on acid conversion (ε) was investigated. It was observed that conversion became more sensitive towards TPA particle size as the EG/TPA feed ratio was lowered. It is advantageous to use the model based on TPA particle size for mass transfer limited esterification reactors. The effect of the monomer feed ratio on conversion, chain length and system heterogeneity can be predicted with this model.magnified image