Full-wave Analysis Technique Research Articles

A unified Green's function analysis of complicated DFB lasers

An efficient full-wave analysis technique for one-dimensional optical domains, known as the recursive Green's function method (RGFM), is presented for evaluation of distributed feedback (DFB) laser cavities with arbitrary material profiles. The method first constructs the Green's function of an inhomogeneous domain and subsequently uses Green's theorem to determine the laser optical field, lasing wavelength, and threshold gain. The technique is applied to investigate the performance of three DFB laser structures: a chirped-grating configuration, a modulated stripe width design, and a reduced duty cycle complex-coupled device. These structures are evaluated in terms of their single-mode lasing behavior and the uniformity of the optical field within the cavity.

Efficient full-wave analysis of stratified planar structures and unbiased TW-FET's

We have developed a rigorous full-wave analysis technique capable of characterizing quasiplanar travelling wave structures, consisting of multilayer dielectrics and conductors of finite thickness, also taking into account dielectric and conductor losses. We have studied boxed embedded microstrips and another complex passive structure, namely the T-gate TW-FET, devoting particular attention to the distribution of current inside the metallization. All structures considered were simulated by means of a desktop computer. We have tested our program by comparing our results with experimental data of embedded microstrips and employed it for the characterization of planar and T-type gates of the FET's without bias.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Analysis of a reflectarray antenna using microstrip patches of variable size

Microstrip reflectarrays typically use tuning stubs on each element to adjust the phase of the reflected field. The authors describe a new approach in which the need for tuning stubs is eliminated and phase control is achieved simply by adjusting the resonant length of the patch elements. The advantages of this approach are described, as are a full-wave analysis technique for computing the phase of the reflected field as a function of patch size and a design curve giving the change in patch size for a desired reflected field phase shift.< >

Integrated horn antennas for millimeter-wave applications

The development of integrated horn antennas since their introduction in 1987 is reviewed. The integrated horn is fabricated by suspending a dipole antenna, on a thin dielectric membrane, in a pyramidal cavity etched in silicon. Recent progress has resulted in optimized low- and high-gain designs, with single and double polarization for remote-sensing and communication applications. A full-wave analysis technique has resulted in an integrated antenna with performance comparable to that of waveguide-fed corrugated-horn antennas. The integrated horn design can be extended to large arrays, for imaging and phased-array applications, while leaving plenty of room for the RF and IF processing circuitry. Theoretical and experimental results at microwave frequencies and at 90 GHz, 240 GHz, and 802 GHz are presented. >

Integrated horn antennas for millimeter-wave applications

This paper reviews the development of integrated horn antennas since their introduction in 1987. The integrated horn is fabricated by suspending a dipole antenna on a thin dielectric membrane in a pyramidal cavity etched in silicon. Recent progress resulted in optimized low and high-gain designs with single and double-polarizations for remote-sensing and communication applications. A fullwave analysis technique have resulted in an integrated antenna with performance comparable to that of waveguide-fed corrugated horn antennas. The integrated horn design can be easily extended to large arrays for imaging and phased array applications while still leaving plenty of room for the rf and w processing circuitry. Theoretical and experimental results at microwave frequencies and at 90, 240 and 802 GHz will be presented.

Millimeter-wave integrated-horn antenna. II. Experiment

For pt.I see ibid., vol.39, no.11, p.1575-81 (1991). The impedance and radiation patterns of a dipole-fed horn antenna in a ground plane are experimentally investigated at microwave and millimeter-wave frequencies. The agreement with the full-wave analysis technique presented in part I is good. The results indicate that for a 70 degrees flare-angle horn, horn apertures from 1.0 lambda -square to 1.5 lambda -square with dipole positions between 0.36 and 0.55 lambda yield good radiation patterns with a gain of 10-13 dB a cross-polarization level lower than -20 dB, and resonant dipole impedances between 40 Omega and 120 Omega . It is also found that the impedance measurements can be safely used for 2-D horn arrays, but the radiation patterns differ because of the Floquet modes associated with the array environment. The integrated horn antenna is a high-efficiency antenna suitable for applications in millimeter-wave imaging systems, remote-sensing, and radioastronomy.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Numerical Spectral Matrix Method for Propagation in General Layered Media: Application to Isotropic and Anisotropic Substrates

A full-wave analysis technique for generalized artisotropic layered media based on a 4x4 field matix method is applied to calculate the propagation constant of a number of microstriplike transmission structures. This technique is very versatile, and allows simultaneous permittivity, permeability, and optical activity anisotropy. Data for higher order modes of single and coupled strip lines in isotropic layered media in the millimeter-wave region are presented. New dispersion data for both low- and high-anisotropy dielectric layered structures are generated for different principal axis crystallographic orientations.