bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mode energy transfer along a circular open chirowaveguide
Authors: Cory H. , Gov S. 
Published: July 2007

AbstractMode energy transfer along a circular open chirowaveguide is analyzed. It is shown that the TE0 and the TM0 are the only unperturbed modes that undergo coupling processes and that if the guide is exclusively excited with the TE01 mode, or the TM01, or both, only these modes are dominant. The energy variation along the guide is then almost periodic and the distance at which the energy transfer is largest is of the order of the radius, making this device attractive as a TE → TM mode converter, especially when a cylindrical geometry is required in a specific circuit design. © 1993 John Wiley & Sons, Inc.
On the TM101 mode of a hemispherical dielectric resonator antenna
Authors: Leung K. W. , Luk K. M. , Lai K. Y. A. , Lin D. 
Published: July 2007

AbstractA hemispherical dielectric resonator antenna axisymmetrically fed by a coaxial probe is investigated both theoretically and experimentally. The input impedance of the lowest‐order TM mode (the TM101 mode) is evaluated by using the variational formula and the result agrees well with measured data. The effects of the probe length and dielectric constant on the input impedance are studied. Finally, the theoretical radiation pattern is compared with that of a bare mono‐pole of a quarter‐wavelength in height. © 1993 John Wiley & Sons, Inc.
A new rectenna circuit using a bow‐tie antenna for the conversion of microwave power to dc power
Authors: And Michael Tran , Nguyen Cam 
Published: July 2007

AbstractA new rectenna circuit is described. The rectenna circuit uses a bow‐tie antenna integrated with a diode. The newly developed bow‐tie rectenna has a high conversion efficiency, is broadband, is not sensitive to the angle of the incident field, has a good match to its circuit, and behaves as a low‐pass filter for dc output. A microwave‐to‐dc conversion efficiency of 79% has been achieved at 2.45 GHz. © 1993 John Wiley & Sons, Inc.
The effects of strain on the microwave performance of SiGe HBTs
Authors: Rosenfeld D. , Alterovitz S. A. 
Published: July 2007

AbstractThe results of a theoretical study of the effects of the strain on the cutoff frequencies of SiGe HBTs are presented. The influence of the strain on the base resistance and transit time, and through them on high‐frequency performance, was taken into account. The positive role played by the strain is demonstrated. © 1993 John Wiley & Sons, Inc.
Cross‐polarization characteristics of a probe‐fed spherical‐circular microstrip patch antenna
Authors: Chen Hong‐Twu , Wong Kin‐Lu 
Published: July 2007

AbstractThe cross‐polarization characteristics of a spherical‐circular microstrip patch antenna excited at TM11 mode by a probe are investigated theoretically. The theoretical treatment is based on a rigorous Green's‐function formulation in the spectral domain. Numerical calculations are performed by using Galerkin's moment method. Numerical results of the cross‐polarization characteristics for different curvature radii of the spherical microstrip antenna are presented and analyzed. It is found that a smaller curvature radius of the spherical microstrip antenna can reduce the cross‐polarized radiation of the circular patch antenna at TM11 mode, and the cross‐polarization level increases with decreasing curvature radius. © 1993 John Wiley & Sons, Inc.
High‐temperature superconductor/III‐V hybrid microwave circuits (invited paper)
Authors: Shen Z‐Y. , Wilker C. , Pang P. S. W. , Carter C. F. , Nguyen V. X. , Laubacher D. B. 
Published: July 2007

AbstractThe electrical parameters of III‐V semiconductor devices were measured at cryogenic temperatures. These data were used for the accurate design of high‐temperature superconductor (HTS)III‐V hybrid microwave circuits. A number of such hybrid circuits, including amplifiers, oscillators, balanced mixers, and a dual channel receiver front end were designed and fabricated. Some of the test data for these circuits are presented. © 1993 John Wiley & Sons, Inc.
Performance of two‐pole bandpass filters photodefined on double‐sided Y‐Ba‐Cu‐O AND Tl‐Ba‐Ca‐Cu‐O thin films
Authors: Miranda F. A. , Toncich S. S. , Bhasin K. B. 
Published: July 2007

AbstractThe performance of 7.3‐GHz two‐pole bandpass filters (5% bandwidth) fabricated on double‐sided Y‐Ba‐Cu‐O and Tl‐Ba‐Ca‐Cu‐O thin films deposited on LaAlO3is discussed. At 77 K, the Tl‐Ba‐Ca‐Cu‐O and Y‐Ba‐Cu‐O superconducting filters exhibited minimum passband insertion losses of 0.3 and 1.2 dB, respectively. An insertion loss of 3.4 dB was measured for an all‐gold filter at 77 K. © 1993 John Wiley & Sons, Inc.
Impact of kinetic inductance effect on high‐Tc
Authors: Kain A. Z. , Pond J. M. , Fetterman H. R. , Jackson C. M. 
Published: July 2007

AbstractHigh‐Q transmission high‐Tcsuperconducting coplanar waveguide resonators have been employed to make accurate measurements of the temperature dependence of the penetration depth via the change in phase velocity. Resonators made from several different film thicknesses are well described using a zero temperature penetration depth and a T‐squared temperature dependence using a full‐wave spectral‐domain model of the coplanar waveguide transmission line. © 1993 John Wiley & Sons, Inc.
Effects of cylindrical curvature on radiation from a microstrip antenna with a thick cover layer
Authors: Hoorfar Ahmad , Gupta K. C. , Chang D. C. 
Published: July 2007

AbstractThe fundamental radiation characteristics of a microstrip antenna on a cylindrical substrate with a thick cover layer is investigated by using a magnetic line source model. Numerical results for the radiation pattern and conductance are presented. It is found that certain combinations of curvature radius and cover‐layer thickness could result in significant distortions in the pattern. Lossy dielectric material may be used to reduce these undesired effects. © 1993 John Wiley & Sons, Inc.
On the radiation sensibility of a microstrip transmission line
Authors: And Renato Cicchetti , Pirone Carmine 
Published: July 2007

AbstractA transmission‐line model excited by distributed generators is used to analyze the voltage and current induced by an external electromagnetic field in a microstrip transmission line. The influence of the electrical and geometrical parameters of the planar structure on the line's response to external transient electromagnetic fields has been analyzed. Design guidelines to reduce the disturbance induced are considered and the optimum choice for the substrate's parameters are discussed. © 1993 John Wiley & Sons, Inc.
On the subzone phase correction of fresnel zone plate antennas
Authors: Guo Y. J. , Barton S. K. 
Published: July 2007

AbstractSubzone phase correction is a practical technique to produce high‐efficiency Fresnel zone plate antennas. In this article a strict theory underlying the technique is presented. A closed‐form expression of the focal field for the subzone phase correcting Fresnel zone plate (FZP) illuminated by a plane wave is given first. The subzone division and the corresponding phase correction are then optimized to produce the maximum focal field intensity. To overcome the difficulty of placing many subzone phase shifters in the narrow outer full‐wave zones, an aperiodic subzone phase correction technique is proposed.
Field‐theory analysis of cross‐iris coupling in circular waveguide resonators
Authors: Zapata J. , Garcia J. , Valor L. , Garai J. M. 
Published: July 2007

AbstractDual‐mode circular waveguide filters employ cross‐iris couplings usually designed by small‐aperture approximations. This Letter presents a full‐wave method, which is able to rigorously analyze irises of any shape, thickness, and size, based on a mixed finite‐element method (FEM) and a mode‐matching technique. The accuracy of the method has been tested by comparing measured and computed data.
Optical‐fiber PPM soliton systems: Implications of the gordon‐haus effect
Authors: Cryan R. A. , Phillips A. J. , Senior J. M. 
Published: July 2007

AbstractThe fundamental limit in transmission distance, associated with the Gordon‐Haus timing jitter, is evaluated for an optical‐fiber pulse position modulation (PPM) soliton system. We demonstrate that soliton PPM is more susceptible to this type of timing jitter and that the maximum span length is limited to 65% of that of an equivalent soliton PCM system. © 1994 John Wiley & Sons, Inc.
A new set of orthogonal polynomial functions for waveguide analysis
Authors: Wang B. K. , Lam K. Y. , Leong M. S. , Kool P. S. 
Published: July 2007

AbstractThis article presents a new numerical procedure involving the use of orthogonal polynomials in a Rayleigh‐Ritz procedure to investigate the wave propagation characteristics of uniform hollow conducting waveguides of polygonal cross section. As examples of the applicability of the new functions, the TM modes in metallic waveguides of rectangular and triangular cross sections have been studied. © 1994 John Wiley & Sons, Inc.
InP‐based lasers on Si substrates with microcleaved mirrors
Authors: Sugo M. , Mori H. , Itoh Y. , Tachikawa M. , Sakai Y. 
Published: July 2007

AbstractAn InP‐based multiple quantum‐well laser diode on a Si substrate with microcleaved mirrors exhibits cw operation at room temperature. Microcleaved mirrors can be fabricated without having to cleave a Si substrate. The laser emits at a 1.54‐μm wavelength and exhibits stable operation even after more than 1000 hours. © 1994 John Wiley & Sons, Inc.
Strained GaInAsP/InP multiple‐quantum‐well lasers for wideband analog and high‐speed digital fiber‐optic networks
Authors: Fukushima T. , Matsumoto N. , Nakayama H. , Ikegami Y. , Namegaya T. , Kasukawa A. , Shibata M. 
Published: July 2007

AbstractCompressively strained 1.3‐μm GaInAsP/InP multiple‐quantum‐well (MQW) lasers suitable for wide‐band analog and high‐speed digital transmissions were fabricated. With the ridge waveguide structure and an optimum well number, a large bandwidth of 11 GHz was achieved. The short‐cavity buried‐heterostructure lasers showed low threshold current (2 to 3 mA) and small turn‐on delay time (<200 ps) at biasless 30‐mA pulse current. © 1994 John Wiley & Sons, Inc.
On the application of Kirchhoff's approximation to scattering from discontinuities in large waveguide ducts
Authors: Ling Hao , Kim Hyeongdong 
Published: July 2007

AbstractA simple Kirchhoff‐based approximation is presented to account for the mode conversion at discontinuities such as bends and steps in open‐ended waveguide ducts. Comparisons with other more numerically exact approaches and with experimental results for a variety of two‐ and three‐dimensional inlet duct configurations show that this approximation is surprisingly accurate when the transverse dimension of the duct is above 5 wavelengths. This approximation reduces the computational burden of predicting the scattering from large inlet ducts. © 1994 John Wiley & Sons, Inc.
Pupil symmetries for identical axial response
Authors: Escalera Juan C. , Campos Juan , Yzuel Maria J. 
Published: July 2007

AbstractIn this article we establish a symmetry condition for nonuniform pupils with different transmission functions to produce the same response along the axis. Besides, these pupils can produce different effects in the transverse response like apodization or hyperresolution. We also show the relation that different annular pupils have to satisfy in order to produce identical axial behavior. Some results of annular color filters that fulfill this condition are given. © 1994 John Wiley & Sons, Inc.
Analysis of a two‐octave polarization rotator using the method of equivalent boundary conditions
Authors: Pereyaslavets Michael L. , Kastner Raphael 
Published: July 2007

AbstractA rapid analysis of a two‐octave, 45° polarization rotator is achieved by the approximate method of equivalent boundary conditions (EBC). Results achieved by this approximation and the conjugate gradient‐FFT (CG‐FFT) appear to be closely matched, with differences well within measurement error. Computation speed is significantly improved when compared with purely numerical techniques. © 1994 John Wiley & Sons, Inc.
On the interpolation of numerically defined surfaces in collimated‐beam dual reflector antennas
Authors: Bergmann J. R. , Hasselmann F. J. V. , Costa L. P. N. , Telxeira F. L. , Rego C. G. 
Published: July 2007

AbstractGeometrical‐optics syntheses of shaped reflector antennas yield numerically defined surfaces that must be interpolated for subsequent evaluation of the radiation field and its check against design specifications. The implementation of three global interpolating functions is explored in connection with a typical dual‐shaped offset reflector antenna designed to produce a collimated beam with high efjkiency and low side‐lobe envelope. © 1994 John Wiley & Sons, Inc.
Combining SDA and fdtd methods for the modeling of planar applicators used in microwave hyperthermia
Authors: Duhamel F. , Dubois L. , Chive M. , Pribetich J. 
Published: July 2007

AbstractAn improved bidimensional finite‐difference time‐domain (2D FDTD) method has been achieved in order to compute all electromagnetic fields in heterogeneous media when planar microstripmicroslot applicators are used for microwave hyperthermia. This method consists of combining 2D FDTD and classical spectral domain approach (SDA). Good agreements are exhibited with classical SDA, thus allowing the study of inhomogeneous media. © 1994 John Wiley & Sons, Inc.
A new design approach for a high‐transimpedance and low‐noise optoelectronic integrated lightwave receiver with 24‐GHz bandwidth
Authors: John Eugene , Das Mukunda B. 
Published: July 2007

AbstractThis article illustrates how the bandwidth of a high‐transimpedance optoelectronic integrated circuit amplifier, involving a metal‐semiconductor‐metal (MSM) photodiode and heterojunction bipolar transistors (HBTs), can be improved by incorporating the concept of emitter RC‐network shunt peaking often used in common‐emitter voltage amplifiers. In the IC amplifier considered, the bandwidth has been shown to increase, with shunt peaking from 17.2 to 24 GHz, with no change of the equivalent input noise current (=2.3 pA/√Hz), arising mainly due to the input transistor's base current and the feedback resistor. © 1994 John Wiley & Sons, Inc.
An efficient approach for the evaluation of the double integrals in the analysis of printed circuit antennas
Authors: Cai M. , Kooi P. S. , Leong M. S. 
Published: July 2007

AbstractA numerical approach for the evaluation of the double integrals that arise in the analysis of printed circuit antennas is developed. In this method, the integration variables in the integrals are transferred to the polar coordinate system (λ, θ). The approach focuses on the fact that the oscillating frequency of the integrand in the azimuth direction θ is nearly proportional to the radius A. An adaptive scheme to increase sampling points in the θ direction is therefore introduced. Numerical results show that the sampling points can be reduced by 50%. © 1994 John Wiley & Sons, Inc.
Automatic generation of the solution path of a parametrized nonlinear circuit in the presence of turning points
Authors: Rizzoli Vittorio , Costanzo Alessandra , Neri Andrea 
Published: July 2007

AbstractThe generation of the solution path of a parametrized nonlinear circuit represents the key step of a computer‐aided stability analysis. When this process is carried out by the Newton‐iteration‐based harmonic‐balance technique coupled with a continuation method, numerical ill conditioning occurs in the vicinity of the turning points due to the singularity of the Jacobian matrix. The Letter introduces a novel switching‐parameter algorithm allowing the turning points to be automatically detected without loss of numerical efficiency. In the neighborhood of the turning point the roles of the parameter and of one of the steady‐state harmonics are interchanged, so that the latter becomes the independent quantity. In this way the singularity is removed, and the analysis at the turning point can be performed with the same accuracy and efficiency as at any ordinary point. The switching criterion is based on the condition number of the conventional Jacobian. © 1994 John Wiley & Sons, Inc.
Automated finite‐element solution of nonlinear optical waveguide problems in two dimensions
Authors: Cvetkovic Srfoa R. , Zhao An Ping , Punjani Minaz 
Published: July 2007

AbstractAn efficient and automated finite‐element package (named WAVEGIDE), which is implemented within the PDE/ProtranTM problem‐solving environment, is extended here to the analysis of two‐dimensional nonlinear optical waveguiding structures. With WAVEGIDE, through an interactive question‐and‐answer session, which requires modest knowledge of programming and minimal effort for the input of waveguide parameters, the problem can be defined using high‐level PDE/ProtranTM commands. To illustrate the ease of use, flexibility, and accuracy of the developed package, numerical results for the first quasi‐TE power‐dependent mode in a buried nonlinear waveguide was presented. The program is available in the public domain. © 1994 John Wiley & Sons, Inc.
The effect of sample rate on propagation measurements
Authors: Stutzman Warren L. , Will Remaklus P. 
Published: July 2007

AbstractThis article presents results from a study on the effect of data sampling rate for earth‐space propagation experiments. Data taken from the Olympus 30‐GHz satellite beacon signal at Blacksburg, VA were sampled at 10 Hz in real time and then postprocessed to obtain effective sampling rates down to 0.1 Hz. Both event and statistical data are presented. © 1994 John Wiley & Sons, Inc.
A ray‐propagation fast multipole algorithm
Authors: Wagner Robert L. , Chew Weng Cho 
Published: July 2007

AbstractA new technique is presented for accelerating the fast multipole method, allowing rapid solution of surface integral equations for wave‐scattering problems. A nonnested, ray‐propagation approach is used to compute a matrix‐vector multiply in O(N4/3) operations, where N is the number of unknowns in the discretized integral equation. © 1994 John Wiley & Sons, Inc.
Signal propagation in the presence of side‐band instability in long fiber links
Authors: Matera F. , Mecozzi A. , Romagnoli M. , Settembre M. 
Published: July 2007

AbstractWe study signal propagation in the presence of the side‐band instability process that is due to the periodic power variation due to the lumped amplifiers. We show that such side bands, which were previously observed for soliton signals, are a general process that show up also for conventional signals. © 1994 John Wiley & Sons, Inc.
Orthogonal‐polarization reflective star couplers
Authors: Barnard C. W. , Chrostowski J. , Kavehrad M. 
Published: July 2007

AbstractNew reflective optical fiber star couplers are proposed. The star broadcasts to all receiwers without excess loss by rotating the polarization of the transmitted light by 90°. The couplers use an orthogonal‐polarization variable reflector that can act as either a full or half reflector. Published by John Wiley & Sons, Inc. © 1994 John Wiley & Sons, Inc.
A novel uniplanar microstrip to slot‐line transition
Authors: Ho Thinh Q. , Hart Stephen M. 
Published: July 2007

AbstractA novel approach for designing a uniplanar microstrip to slot‐line transition for MIC/MMIC and antenna applications is described. A slot‐line radial stub is utilized to create resonance conditions at the junction of the two transmission lines so that maximum intermodal power transfer occurs. Excellent insertion loss and impedance match is obtained over a 30% bandwidth. © 1994 John Wiley & Sons, Inc.
Matched loads simulation using ghost basis functions for moment‐method analysis: Applications to microwave planar circuits
Authors: Delabie C. , Delplanque Y. , Pribetich P. , Kennis P. 
Published: July 2007

AbstractA clever way to simulate numerical matched loads is presented and applied in the mathematical framework of the moment method. This approach presents a lot of advantages with regard to other numerical matched load simulations, and could be used whateier the shape of the planar circuit without the help of the characteristic impedance concept. Results show that very good efficiency is obtained for the reflection coefficient of such matched loads. Typical results are exhibited for S‐parameter determination of multipart microstrip circuits. © 1994 John Wiley & Sons, Inc.
Multireference detection using iterative joint transform operation with composite filtering
Authors: Yu Francis T. S. , Cheng Feng 
Published: July 2007

AbstractIn this article we shall introduce an interative joint transform operation for multireference detection utilizing composite intensity compensation filtering. This technique essentially uses the normalized correlation peak intensity values as the iterative feedback into the input and Fourier planes to update the weight coefficients for the reference patterns and the composite intensity compensation filter. As shown in the simulated results, this technique can detect highly similar objects which cannot normally be differentiated with the conventional joint transform correlator. The effect due to noise is also investigated, in which we have shown that the technique improves the performance of the joint transform correlation. © 1994 John Wiley & Sons, Inc.
A perturbative approach to the scattering from a perfectly conducting wedge with a crack or gap in one of its faces
Authors: Pelosi G. , Manara G. , Monorchio A. , Coccioli R. 
Published: July 2007

AbstractA perturbative solution is described for determining the field scattered by a perfectly conducting wedge with a crack or gap in one of its faces. The wedge is illuminated by a plane wave perpendicularly incident on its edge. The gap aperture is modeled by an equivalent surface impedance strip. Numerical results are presented to demonstrate the applicability of this perturbative technique. © 1994 John Wiley & Sons, Inc.
Characterization of dissipative losses in microwave circuits
Authors: Livernois Thomas G. 
Published: July 2007

AbstractThe analytical expression for the fractional power dissipated by a microwave circuit is derived in terms of the scattering parameters. Consideration is given to both complex and real port reference impedances. Theoretical values of fractional dissipated power, computed using a full‐wave analysis technique, are compared to experimentally obtained data. © 1994 John Wiley & Sons, Inc.
Correction factors for fresnel knife‐edge diffraction based on uniform theory of diffraction results
Authors: Legendre J. F. , Chassay G. 
Published: July 2007

AbstractIn this article shortcomings of the Fresnel knife‐edge theory are discussed and simple analytical correction factors are obtained with the help of UTD single‐wedge results. This new formulation is especially helpful in radio links where great diffraction effects are a concern. © 1994 John Wiley & Sons, Inc.
Resonant‐frequency calculation for electrically thick rectangular microstrip patch antennas using a dielectric‐loaded inhomogeneous cavity model
Authors: Lee Ilsu , Vorst André Vander 
Published: July 2007

AbstractA new antenna model and a new formula for calculating the resonant frequency of an electrically thick rectangular microstrip patch antenna are presented. The model is based on the use of the Schwarz‐Chritoffel transformation and on a dielectric‐loaded inhomogeneous rectangular cavity. The resonant frequency of the dominant mode is obtained by using a variational method. © 1994 John Wiley & Sons, Inc.