T.E. van Deventer

Millimeter-wave bistatic scattering from ground and vegetation targets

A 35-GHz bistatic radar system was used to measure the attenuation through trees and the bistatic scattering pattern of tree foilage. The data were found to be in good agreement with a first-order multiple scattering model. Measurements were also made to study the angular vibration of the bistatic scattering coefficient of a smooth sand surface, a rough sand surface, and a gravel surface. The measurements, which were made for HH, HV (horizontal transmit, verticle receive), and VV polarization configurations over a wide range of the azimuth angle and the scattering angle, provide a quantitative reference for the design and use of millimeter-wave bistatic radar systems. >

An integral equation method for the evaluation of conductor and dielectric losses in high-frequency interconnects

An integral equation method is developed to solve for the complex propagation constant in multilayer planar structures with an arbitrary number of strip conductors on different levels. Both dielectric losses in the substrate layers and conductor losses in the strips and ground plane are considered. The Greens function included in the integral equation is derived by using a generalized impedance boundary formulation. The microstrip ohmic losses are evaluated by using an equivalent frequency-dependent impedance surface which is derived by solving for the fields inside the conductors. This impedance surface replaces the conducting strips and takes into account the thickness and skin effect of the strips at high frequencies. The effects of various parameters such as frequency, thickness of the lines, and substrate surface roughness on the complex propagation constant are investigated. Results are presented for single strips, coupled lines, and two-level interconnects. Good agreement with data available in the literature is shown. >

High frequency conductor and dielectric losses in shielded microstrip

An integral equation method is developed for calculating the dispersion of imperfectly conducting microstrip lines. Both dielectric losses in the substrate and conductor losses in the strips and ground plane are considered. Multiple conductors on several layers can be studied using an impedance boundary formulation for the derivation of the Greens function. The microstrip losses are evaluated by using a frequency-dependent surface impedance which is derived by solving the fields in the conductors. This surface impedance replaces the conducting strip and takes into account the thickness and skin effect of the strip at high frequencies. Phase constant and attenuation for single and coupled strips are presented. Good agreement with data available in the literature is shown.<<ETX>>

High frequency characterization of high-temperature superconducting thin film lines

An integral equation approach is used to calculate the propagation characteristics of high-temperature thin-film superconducting lines at high frequencies. To evaluate losses in these lines, the superconducting strips are replaced by frequency-dependent surface impedance boundaries. The values of these surface impedances are measured experimentally by a stripline resonator technique. Using this method, phase and attenuation constants as well as characteristic impedance are evaluated and presented as functions of frequency and several other parameters.<<ETX>>

Analysis of conductor losses in high-speed interconnects

This paper describes the influence of conductor losses on the crosstalk between coupled interconnecting lines using an integral equation method. The method combines a full-wave space domain Greens function in the dielectric regions with a quasi-static Greens function in the conductors. Following this procedure, propagation characteristics are derived in the frequency and time domain and presented for various geometries. >

High Frequency Characterization of High Temperature Superconducting Thin-Film Lines

ABSTRACT An integral equation approach is applied to calculate the propagation characteristics of high temperature thin-film superconducting lines at high frequencies. To evaluate losses in these lines, the superconducting strips are replaced by frequency-dependent surface impedance boundaries. The values of these surface impedances are measured experimentally by a TE01 cavity technique. Using this method, a parametric study is performed where phase and attenuation constants as well as characteristic impedance are evaluated as functions of frequency, temperature, permittivity and geometry of the structure.

A planar integral equation method for the analysis of dielectric ridge structures using generalized boundary conditions

A novel method is developed to calculate the propagation characteristics of dielectric ridge structures in high-frequency monolithic integrated circuits. First, the electric field in the dielectric ridge is expressed in terms of a polarization current from which an equivalent surface current density is defined. Further, generalized boundary conditions are enforced in order to provide a simple integral equation. Results derived by this modified integral equation approach give excellent agreement with other numerical methods. The main advantage of this technique is that it simplifies greatly the analysis of three-dimensional complex structures.<<ETX>>

A study of sub-millimeter wave coupled dielectric waveguides using the GIE method

The coupling properties of coupled dielectric waveguides were evaluated by using a novel and powerful method, the GIE (generalized integral equation) method, which relies on the concept of equivalent planar polarization dipole moments to simulate the guides. Generalized impedance boundary conditions are enforced to provide a simple planar integral equation. This method can account for multiple dielectric strips on different levels. Phase constants of the different modes and coupling characteristics were calculated for several structures, such as rib waveguides and insulated image guides.<<ETX>>

A novel method for the characterization of LSE-type dielectric waveguides

A novel method is developed to calculate the propagation characteristics of dielectric ridge structures in high frequency monolithic integrated circuits. First, the electric field in the dielectric ridge is expressed in terms of a polarization current from which an equivalent surface current density is defined. Further, generalized boundary conditions are enforced in order to provide a simple integral equation. Results derived by this modified integral equation approach give excellent agreement with other numerical methods. The main advantage of this technique is that it simplifies greatly the analysis of three-dimensional complex structures.