C. Seguinot

Microwave performance prediction of a III–V semiconductor electrooptic waveguide modulator

The use of microwave modulations of optical waves allows one to obtain devices with very large bandwidths. Designers must solve two problems, one more specifically relevant to the optical field, the other in the microwave frequency range. The purpose of this paper is to focus the attention of optical device designers on microwave problems that occur when such modulators are made. To do so, we give some quantitative results relative to the microwave characteristics of such devices, when the hybrid nature of the microwave mode is taken into account.

Crosstalk Phenomenon in Coupled Microstrip Lines Laid on Semi-Conducting Substrates

Crosstalk phenomena and pulse propagation in coupled microstrip lines on insulating and semiconducting substrates are analysed. Propagation characteristics of these lines are obtained by Spectral Domain Analysis in order to avoid any error involved by the use of analytical model and T.E.M. approximation. Time domain results are calculated by a conventional fast Fourier transform. Effects of semiconducting layer, substrate thickness, lines spacing and length, loading impedances, on crosstalk and transfer are investigated.

Scattering Parameters and Mode Conversion in Asymmetric CPW-Microstrip Overlap Transitions

In this communication, an asymmetric overlay transition between a microstrip and a CPW is studied. The mode conversion phenomenon is characterized by an efficient full-wave approach associated with the Matrix Pencil post-treatment.

An Extension of the NML simulation to the 3D Spectral Domain Analysis using Triangular Subdomain Functions

A clever way to simulate Numerical Matched Loads is presented and applied in the mathematical framework of the 3D Spectral Domain Analysis when triangular subdomain functions are used as both expansion and testing functions in the Moment Method.

Modelling of Superconducting Interconnections and Analysis of Crosstalk, Propagation Delay, and Pulse Distortion in High-Speed GaAs Logic Circuits

Crosstalk phenomena and pulse propagation in metallic and superconducting coupled microstrip lines on insulating and semiconducting substrates are analysed in this communication. Propagation characteristics of these lines are obtained by a numerical formulation which is an extension of the well known Spectral Domain Approach in order to simulate the nature of the strips and to avoid the errors involved by the use of analytical model or TEM approximation. Time domain results are determined by a conventional fast Fourier transform. Effects of the lossy nature and the thickness of the strips, semiconducting layer, substrate thickness, lines length, loading impedances, on crosstalk and transfer are investigated.

Desktop Computer Models for Coplanar Lines Laid on Semiconductor Layers for C.A.D.

For CAD simulation, it is necessary to determine the frequency behaviour of coplanar lines laid on semiconductor substrates. Exact analysis can be performed by using numerical technics such as S.D.A. or Mode Matching. However such analysis can not be included in C.A.D. programs. For this purpose, we present an original model for coplanar lines laid on semiconductor substrates, which take into account both the influence of thickness metallization and dielectric cap layer. The validity of our models is tested by comparison with mode matching and S.D.A. results.