bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acousto‐optic star couplers for routing and broadcasting in local area networks
Authors: Helaly Anwar M. , Abushagur Mustafa A. G. 
Published: July 2007

AbstractAcousto‐optic deflectors are introduced to be used as star couplers that perform broadcasting and routing in local area networks. Configurations for both single‐wavelength and multiwavelength broadcast‐and‐select networks are proposed. A routing network in which both the input and output ports are wavelength tunable is also shown. Acousto‐optic devices provide these networks with the advantage of low insertion loss, simplicity, and compactness, because one device can handle a large number of ports. Analysis for these networks is presented and computed simulation results are shown. The proposed routing network is not limited to the use of acousto‐optic deflectors, because conventional blazed diffraction gratings can be used. © 1994 John Wiley & Sons, Inc.
The effect of noise in the data on the Cauchy method
Authors: Adve R. , Sarkar T. 
Published: July 2007

AbstractIn this article the effect of noise in the data on the Cauchy method is discussed. The noise is assumed to be zero mean and Gaussian. The resulting random variable is a ratio of two Gaussians. The theoretical probability density function is verified by numerical simulation. © 1994 John Wiley & Sons, Inc.
Novel characteristics of radiation patterns of a pseudochiral point‐source antenna
Authors: Toscano Alessandro , Vegni Lucio 
Published: July 2007

AbstractWe present certain novel characteristics of the radiation pattern of a pseudochiral point‐source antenna, which consists of an elemental antenna embedded in a grounded pseudochiral substrate in the presence of an isotropic half‐space. The pseudochiral Ω medium is a new synthetic bianisotropic material, recently introduced by Engheta and Saadoun [1]. The expression of the electric field radiated by a pseudochiral grounded slab is given in a form such as to simplify the extraction of noticeable information to be used during the project, about the influence of frequency, constitutive parameters, thickness of the slab, and position of the electric source. © 1994 John Wiley & Sons, Inc.
Theoretical analysis of an open‐ended coaxial probe on a cylinder of finite thickness
Authors: de Langhe P. , Martens L. , de Zutter D. 
Published: July 2007

AbstractThe admittance of an open‐ended coaxial probe on a dielectric cylinder of finite thickness surrounded by a cylindrical outer layer of equal thickness but with a different dielectric constant is calculated analytically. The cylinder and the surrounding material are backed by a metal plate. The theoretical results indicate up to which frequency the measured value of the dielectric constant of the cylindrical sample remains independent of its lateral dimensions. © 1994 John Wiley & Sons, Inc.
Optical beam steering using a liquid‐crystal television panel
Authors: Tanone Aris , Zhang Z. , Uang C.‐M. , Yu Francis T. S. , Gregory Don A. 
Published: July 2007

AbstractA blazed grating can be generated using a programmable liquid‐crystal television (LCTV) panel. Despite the effects of phase mismatch, phase quantization, and pixel addressing of the panel, optical beam steering is possible, particularly for small angle deflection applications. © 1994 John Wiley & Sons, Inc.
Temperature distribution in biological media by microwave radiometry: Preliminary results
Authors: Bregni S. , Caorsi S. , Gragnani G. L. 
Published: July 2007

AbstractMultispectral microwave radiometry for temperature reconstruction inside biological media is considered. Radiometric data on simulated living tissues have been obtained with a multifrequency radiometer in the frequency range 1.5–3.5 GHz. Temperature retrieval has been modeled as the solution of a first‐kind integral equation, based on the theory of radiative transfer. An example of temperature retrieval is reported. Results compare favorably with experimental measures. © 1994 John Wiley & Sons, Inc.
Optical low‐coherence reflectometry (OLCR) for dimensional monitoring of sheet‐grown silicon
Authors: Lawson C. M. , Michael R. R. 
Published: July 2007

AbstractWe report cross‐sectional thickness and flatness measurements for edge‐defined film‐fed growth (EFG) solar silicon using optical low coherence reflectometry (OLCR). The measurement accuracy is ±1.5 μm with the sensor head positioned 1 cm away from the EFG silicon under test. © 1994 John Wiley & Sons, Inc.
Analysis of probe‐fed spherical‐circular microstrip antennas using cavity‐model theory
Authors: Chen Hong‐Twu , Wong Kin‐Lu 
Published: July 2007

AbstractThis article presents a cavity‐model analysis of spherical‐circular microstrip antennas. In this study, expressions for the input impedance and far‐zone radiated fields are derived and given. Numerical results of the input impedance and radiation patterns for the antenna excited at the TM11 mode are presented, and are compared with those obtained by the generalized transmission line model and the full‐wave approach to discuss the applicability of the cavity‐model theory for the analysis of spherical microstrip antennas. © 1994 John Wiley & Sons, Inc.
Power distributed amplifier with input‐output combiners
Authors: D'Agostino Stefano , Paoloni Claudio 
Published: July 2007

AbstractA novel distributed amplifier topology is proposed to increase the power performance and the gain. In comparison with the conventional configuration, a considerable advantage is obtained by introducing Lange couplers at the input and output ports of the amplifier. Design examples are discussed to confirm the validity and the effectiveness of the proposed topology. © 1994 John Wiley & Sons, Inc.
Variational formulation of electromagnetic boundaryvalue problems involving anisotropic media
Authors: Jin Jianming , Chew Weng Cho 
Published: July 2007

AbstractA variational formulation is presented for electromagnetic boundaryvalue problems involving anisotropic media. Specific functionals are given, along with a discussion of the property of the resulting numerical system, for general problems involving general anisotropic media, for lossy problems involving anisotropic media having symmetric permittivity and permeability, and for lossless problems involving anisotropic media having Hermitian permittivity and permeability. © 1994 John Wiley & Sons, Inc.
Time‐domain modeling of the impedance boundary condition for an oblique incident perpendicular‐polarization plane wave
Authors: Wang Bing‐Zhong , Zhou Na 
Published: July 2007

AbstractIn this article, the frequency‐domain impedance boundary condition used for a thin layer coating over perfect conductors is transformed to a time‐domain impedance boundary condition (TDIBC) for the case of ablique incident perpendicular‐polarization plane wave, resulting in a partial differential equation in space and time. Discretization of the TDIBC to effeciently handle the thin layer coating is presented in the context of the time‐domain finite‐difference (TDFD) technique. The TDFD solutions using our TDIBC are in good agreement with the analytical results. © 1994 John Wiley & Sons, Inc.
How does threshold detection limit atmospheric turbulence in number state optical channels?
Authors: Fares Doaa A. 
Published: July 2007

AbstractIn this article, analysis for the recently considered photon number state optical channel [1–3] is presented. Under atmospheric turbulence conditions, the channel performance is highly affected and deteriorated. Therefore, coding‐in particular Reed‐Solomon block codes [4]‐becomes a must. In this presentation, the optimal threshold performance conditions are calculated and are shown to prove their strong control on the channel turbulence, yielding reliable communication. Other channel measures such as channel transparency, information efficiency, and transmission rate are investigated. © 1994 John Wiley & Sons, Inc.
Slow‐wave analysis on double‐layered substrates
Authors: Hindy Moataza A. 
Published: July 2007

AbstractA full‐wave analysis of a slow‐wave microstrip transmission line on a ferromagnetic semiconductor with an insulator is presented. The spectral‐domain method with a sampling theorem is used. A new current distribution is applied. The slow‐wave factor and the characteristic impedance are calculated for different material conductivities σ with variable applied dc magnetization. © 1994 John Wiley & Sons, Inc.
Full‐wave analysis using a tangential vector finite‐element formulation of arbitrary cross‐section transmission lines for millimeter and microwave applications
Authors: Helal M. , Legier J. F. , Pribetich P. , Kennis P. 
Published: July 2007

AbstractA tangential vector finite‐element formulation is implemented to deal with arbitrary cross section and metallic strip shape. Classical planar transmission lines as well as nonconventional cross‐section waveguides such as the new microshield line are treated. Effects on propagation characteristics for these lines are studied when the metallization shape is approximated by a lossy trapezoid area. © 1994 John Wiley & Sons, Inc.
An efficient two‐dimensional discrete fourier transform analysis of periodic pixels of TFT/LCDs
Authors: Lin Jin‐Shin , Lee Wei‐Yu 
Published: July 2007

AbstractAn efficient 2D DFT method is proposed to investigate the characteristics of periodic pixels of TFT/LCDs. The electric field distributions under the pixel electrode are illustrated in three dimensions for the first time. A two‐capacitor model derived based on the coupling effect is also presented. Means of reducing capacitance to obtain the high‐density pixels of TFT / LCDs are suggested. Numerical results are given to establish useful guidelines for design. © 1994 John Wiley & Sons, Inc.
Quasicomplex modes of boxed coplanar lines on lossy dielectric substrate for millimeter‐wave applications
Authors: Delplanque Y. , Huret F. , Kennis P. , Pribetich P. 
Published: July 2007

AbstractIn this Letter, we propose to show the existence of quasicomplex modes of boxed coplanar lines laid on a lossy dielectric substrate for millimeter‐wave applications, using the method of lines with non‐equidistant discretization. These quasicomplex modes are defined by studying the behavior of the two complex solutions of the propagation problem of the classical lossless boxed coplanar line versus the losses of dielectric substrate. © 1994 John Wiley & Sons, Inc.
Spectral electric green's dyad for a grounded bianisotropic slab fed by a three‐dimensional point source
Authors: Toscano Alessandro , Vegni Lucio 
Published: July 2007

AbstractThe subject of this article is the analysis of planar stratified structures with a general bianisotropic grounded slab fed by a threedimensional electric point source. The electromagnetic problem is solved in terms of the spectral electric Green's dyad. The elements of the first and third column of the spectral Green's dyad are directly derived from the transmission line equations satisfied by the electromagnetic field in the two‐dimensional Fourier domain. The reaction theorem and the Parseval theorem are then applied to the spectral electromagnetic field, and the elements of the second column of the spectral Green's dyad are provided. Finally, as an application of the theory, we present the expression of the Gyy term when the bianisotropic grounded slab is a pseudochiral one. © 1994 John Wiley & Sons, Inc.
Introduction of radiating losses in the time‐domain transmission‐line method
Authors: Relneix A. , Jecko B. 
Published: July 2007

AbstractThe classical transmission‐line method allows the study of the propagation of a TEM mode along a line. Then, if it is possible to consider nonlocalized losses on a line, the radiation phenomena are not taken into account. In this article, we propose a modification of the transmission‐line method to include radiation phenomena due to discontinuities of impedance or nonrectilinear lines. © 1994 John Wiley & Sons, Inc.
Broadwall slot coupling into butt‐ended waveguide
Authors: Rengarajan Sembiam R. , Elliott Robert S. 
Published: July 2007

AbstractWe present an analysis of a slot cut in a broadwall of a rectangular waveguide, coupling into a semiinfinite rectangular waveguide capped by a conducting transverse plate containing the slot. Slots coupling into butt‐ended waveguides are employed in test fixtures in slot array applications. Pertinent integral equations for the slot‐aperture electric field are solved by the method of moments, and scattering characteristics of slot couplers for butt‐ended guides are deduced. Numerical results indicate limitations of these couplers for applications involving reduced‐height guides. © 1994 John Wiley & Sons, Inc.
Sensitivity penalty in optically preamplified ppm with slot timing jitter impairment
Authors: Elmirghani Jaafar M. H. , Cryan Robert A. 
Published: July 2007

AbstractThe impact of timing jitter on PPM utilizing an erbium‐doped fiber amplifier (EDFA) front end is considered. In the absence of jitter the sensitivity calculations indicate that EDFA PPM offers 7.9–dB sensitivity improvement over EDFA PCM at 622 Mbit/s and λ = 1.53 μm. An original analysis and results are presented for the impact of the extracted slot clock timing jitter on EDFA PPM sensitivity. The jitter sensitivity penalty is shown to vary between 0.15 and 1.9 dB for the range of parameters considered. The selection of the slot phase‐lock loop (PLL) bandwidth that minimizes the jitter penalty is investigated. © 1994 John Wiley & Sons, Inc.
Anisotropic intrasignal coupling in photorefractive linbo3
Authors: Zhao Dazun , Zhou Hanying , Zhao Feng , Yu Francis T. S. 
Published: July 2007

AbstractIntrasignaling coupling in a LiNbO3 photorefractive crystal is studied. It is shown that the anisotropy nature of the effective electrooptic coefficient of this crystal results in an orientation‐dependent intrasignal coupling. Analytical solutions for one‐dimensional intrasignal coupling are derived for a‐axis and b‐axis orientations, which enables us to estimate the maximum beam field angle and the maximum crystal thickness for a given intensity distortion due to the coupling. The results are thus illustrative to applications of this crystal in areas such as holographic data storage, interconnection, spatial mode conversion, et cetera. © 1994 John Wiley & Sons, Inc.
The two‐point target technique for free‐space permittivity measurements of lossy dielectrics
Authors: Yin Hongcheng , Zhang Wenxun , Xiao Zhihe , Huang Peikang 
Published: July 2007

AbstractA new technique for permittivity measurements of lossy dielectrics is presented. It is based on the measurements of backscattering cross section and linear deviation (angular glint) of a two‐point target, consisting of a conducting sphere with a dielectric one or a conducting one coated by the material under test. Because the linear deviation is proportional to the derivative of phase versus aspect angle, this technique overcomes the difficulty encountered in accurately measuring the phase in free space. Moreover, the choice of spherical targets, makes positioning less critical. The effectiveness of such a technique is verified by numerical simulations and measurements. © 1994 John Wiley & Sons, Inc.
A full‐wave analysis of tuning and coupling posts in dual‐mode circular waveguide filters
Authors: Montejo‐Garai J. , Valor L. , Garcia J. , Zapata J. 
Published: July 2007

AbstractA generalized scattering matrix of a circular waveguide with several posts inserted has been derived. The number of posts can be selected from one to eight and placed at 45° angles on the waveguide perimeter. Computation is based on an automated finite‐element‐mode‐matching method that only requires the main geometrical dimensions as input data. A structure containing three screws inserted in a dualmode cylindrical cavity, iris coupled to input and output rectangular waveguides, has been analyzed. Excellent agreement with measured data has been found. © 1994 John Wiley & Sons, Inc.
Full‐wave analysis of input impedance and patch current distribution of spherical annular‐ring microstrip antennas excited by a probe feed
Authors: Chen Horng‐Dean , Wong Kin‐Lu 
Published: July 2007

AbstractThis article presents a full‐wave analysis of probe‐fed spherical annular‐ring microstrip antennas. The formulation of the input impedance is given, and numerical results of the input impedance and the surface current distribution on the annular‐ring patch excited at TM12 mode are calculated and analyzed. It is found that several other modes are usually excited with the excitation of the TM12 mode. The corresponding surface current distributions for these degenerate modes are presented and discussed. © 1994 John Wiley & Sons, Inc.
Modal analysis of optical waveguides using prony's method and bpm
Authors: Chamorro‐Posada Pedro , Gómez‐Alcalá Rafael , Javier Fraile‐Peláez F. 
Published: July 2007

AbstractWe present the application of Prony's method to the problem of computing the complex propagation constants of guided optical modes from data obtained with the beam propagation method (BPM). Prony's method provides accurate results for the complex propagation constants and also gives the amount of power carried by each of these modes as well as their relative phases, for both absorbing and nonabsorbing waveguides. © 1994 John Wiley & Sons, Inc.
An extended fukui‐like formula for the minimum‐noise figure of microwave fets
Authors: Bonani Fabrizio , Ghione Giovanni 
Published: July 2007

AbstractThe article presents an extension of the well‐known Fukui formula for the minimum noise figure of microwave FETs, based on a complete small‐signal equivalent circuit including parasitic elements, the feedback capacitance Cgd, and the output admittance (Gds and Cds). We show that the simplified circuit neglecting all of the above elements, on which most Fukui‐like expressions are based, overestimates NFmin, mainly because Cgd is discarded; moreover, the linear approximation of NFmin(f) from the complete circuit is more accurate than the quadratic one, while parasitic inductances affect the terms of the series expansion of NFmin in powers of f from the third order only. © 1994 John Wiley & Sons, Inc.
The effects of magnetic biasing fields on the far‐field distributions of source on composite ferrite media
Authors: Wenyan Yin , Wei Wan , Wenbing Wang 
Published: July 2007

AbstractIn this article the radiation characteristics of a dipole antenna on grounded composite ferrite structures are studied using the generalized spectral‐domain–exponential‐matrix technique. Numerical results are presented to show the effects of internal dc magnetic bias fields, operating frequency, geometrical sizes, and losses of substrates on the radiation pattern and scanning characteristics of dipoie antenna. The figures show that it is possible to obtain an optimum radiation pattern by choosing suitable constitutive and geometrical parameters of ferrite materials. © 1994 John Wiley & Sons, Inc.
Resonant frequency of a slot‐coupled cylindrical‐rectangular microstrip structure
Authors: Wong Kin‐Lu , Chen Yeong‐Chin 
Published: July 2007

AbstractThe resonance problem of a slot‐coupled cylindrical‐rectangular microstrip structure is investigated by using the exact derived Green's functions for the structure in a spectral‐domain moment‐method solution. The resonant frequencies of the slot‐coupled microstrip structure with various curvature radii are calculated and presented. It is observed that the resonant frequency is affected by both the slot length and the curvature radius. © 1994 John Wiley & Sons, Inc.
Analysis of microstrip step discontinuities in mics printed on anisotropic substrates using the method of moments
Authors: Cain Jeffrey , Beker Benjamin 
Published: July 2007

AbstractThis article presents a full‐wave analysis of microstrip step discontinuities in shielded MICs that are printed on anisotropic substrates, characterized by both permittivity and permeability tensors. The numerical procedure utilizes the method of moments with rooftop basis functions for current expansion and testing. Although the work presented herein emphasizes step junctions, more complicated microstrip discontinuities can easily be realized as well. Numerical results show good agreement with independent data for biaxial substrates. © 1994 John Wiley & Sons, Inc.
Frequency dependent finite‐difference–time‐domain [(fd)2td] formulation applied to ferrite material
Authors: Melon C. , Leveque Ph. , Monediere T. , Reineix A. , Jecko F. 
Published: July 2007

AbstractWhen subjected to a constant magnetic field, ferrites exhibit anisotropic constitutive parameters. This anisotropy can be described in the frequency domain by using a permeability tensor [μ(ω)] instead of the usual scalar permeability. This article introduces a new method to analyze saturated ferrite structures by a FDTD algorithm where the convolution between the permeability tensor [μ(t)] = F−1 ([μ(ω)]) and the magnetic field H(t) = F−1 (H(ω)) are to be calculated. Results are obtained for a two‐dimensional problem and are compared with those given by direct differential FDTD algorithm [1] and a mode‐matching method [2]. © 1994 John Wiley & Sons, Inc.
Effect of four‐wave mixing on the performance of subcarrier multiplexing (scm) catv systems
Authors: Betti S. , De Marchis G. , Matera F. 
Published: July 2007

AbstractThe effect of four‐wave mixing on the performance of CATV‐SCM systems, in which the optical carrier is either amplitude or phase modulated, has been evaluated, considering both direct and coherent detection. Four‐Wave‐Mixing is a nonlinear phenomenon arising in single‐mode fibers when input optical power is too high and / or channel spacing is excessively narrow. The penalty induced by this phenomenon on the carrier‐to‐noise ratio has been evaluated assuming the FWM as a noise process that affects the amplitude and phase of the useful signal. © 1994 John Wiley & Sons, Inc.
Characteristics of row withdrawn surface acoustic wave reflective dot dispersive delay lines
Authors: Tuli Suneet , Bhattacharyya A. B. 
Published: July 2007

AbstractThe effect of row withdrawal in surface acoustic wave reflective dot array dispersive delay lines has been investigated, and the simulated multifrequency, constant fractional chirp bandwidth operation of such a device has been experimentally validated. Utilizing appropriate input/output interdigital transducers, the approach enables higher frequency and increased time‐bandwidth product operation of reflective array devices, with relaxed mask‐making and lithography constraints. © 1994 John Wiley & Sons, Inc.
An explicit time‐domain method using three‐dimensional whitney elements
Authors: Todd Elson J. , Sangani H. , Chan C. H. 
Published: July 2007

AbstractA new three‐dimensional time‐domain method is proposed. The computational domain consists of a union of tetrahedrons with electric fields assigned on the edges. Fields are updated from the integral form of Maxwell's equations in conjunction with the use of Whitney two‐form elements. A rectangular waveguide is modeled as an example. © 1994 John Wiley & Sons, Inc.
Self‐timed p‐i‐n‐hbt ppm receivers
Authors: Elmirghani J. M. H. 
Published: July 2007

AbstractAn original analysis and results are presented for the sensitivity and self‐timing of a hybrid p‐i‐n, heterojunction bipolar transistor pulse position modulation (p‐i‐n‐HBT PPM) strategy at 622 Mbit/s and λ = 0.85 μm. The results indicate a significant performance improvement over a comparable p‐i‐n‐HBT PCM system. The proposed strategy can find application in optical signal distribution at high bit rates in areas such as optical back planes and multiprocessor systems. The self‐timing of the hybrid is addressed and original results are presented for the extracted slot clock timing variance and the associated jitter wrong slot error (WSE) probability, resulting in specifications on the optimum PPM order, fiber bandwidth, and phase‐lock loop (PLL) bandwidth under self‐timing. © 1994 John Wiley & Sons, Inc.