Frequency-domain Transmission Line Matrix Method Research Articles

Toward the Coupling of a Discontinuous Galerkin Method With a MoM for Analysis of Susceptibility of Planar Circuits

We aim at coupling a method of moments, the Wave Concept Iterative Procedure, and the Hybridizable Discontinuous Galerkin (HDG) method to study electromagnetic susceptibility of innovative planar circuits in 3-D. Hybridizing the Wave Concept Iterative Procedure with volumic methods such as the Frequency-Domain Transmission Line Matrix method, the finite-element method, and the HDG method in 2-D is a first step for the validation of the proposed coupling technique. The considered problem is Maxwell's equations in the frequency domain. Three test cases in 2-D and a preliminary result in 3-D are provided.

Computationally Efficient MR-FDPF and MR-FDTLM Methods for Multifrequency Simulations

We propose a modification of the multi-resolution frequency domain ParFlow (MR-FDPF) method that allows simulating radio propagation channels in a frequency range. The performance of the proposed MR-FDPF implementation has been analyzed based on different realistic propagation scenarios. We also analyze the possibility of applying the multi-resolution frequency domain approach to the well-known transmission-line matrix method. The proposed multi-resolution frequency domain transmission-line matrix method provides a computationally efficient way of modeling radio wave propagation in three-dimensional space at multiple frequencies.

2D FDTLM HYBRIDIZATION WITH MODAL METHOD

This article focuses on the 2D hybrid technique between the Frequency Domain Transmission Line Matrix Method (FDTLM) and the Wave Concept Iterative Procedure (WCIP). 3D hybridization has already been studied, but results may be improved through a better knowledge of method order. Consequently, developing 2D hybridization aims at understanding the hybridization in simplest problems, especially because Transverse Electric (TE) and Transverse Magnetic (TM) are uncoupled. Our study dwells on accuracy and convergence order of the 2D hybrid method, which will help for 3D mesh use. In this perspective, the scattering nodes and electromagnetic flelds expressions are established in the 2D general case with anisotropic materials. As a result, validation examples are presented to check the approach.

On the Relationship Between the Time-Domain and Frequency-Domain TLM Methods

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The time- and frequency-domain transmission line matrix (TLM) methods have been developed and shown to be effective and powerful in solving electromagnetic problems. However, their direct relationship has not been clearly described so far. In this letter, we show that if a time-domain TLM method is developed, its corresponding frequency-domain counterpart can also be obtained through the discrete time Fourier transform; in a similar manner, if a frequency-domain TLM method is developed, its time-domain counterpart can also be obtained through the inverse discrete time Fourier transform. The choice of using the frequency- or time-domain depends very much on the types of the problems to be solved and the familiarity of a user with the methods. </para>

TFDTLM-a new computationally efficient frequency-domain transmission-line-matrix method

In this paper, a new computationally efficient frequency-domain transmission-line matrix (FDTLM) approach is introduced. The new approach combines the superior features of both the time- and the frequency-domain transmission-line matrix (TLM). It is based on a steady-state analysis in the frequency domain using transient analysis techniques and, hence, is referred to as the transient frequency-domain transmission-line matrix (TFDTLM). On the contrary, of all other frequency-domain techniques, the TFDTLM has the advantage of being able to extract all the frequency-domain information in the frequency range of interest from only one simulation. This special feature of the TFDTLM makes it computationally more efficient as compared to any other FDTLM method. The TFDTLM employs digital filter approximations for modeling wave propagation in inhomogeneous frequency dispersive media. The filters can be thought of as some type of compensation equivalent to the stubs in a time-domain transmission-line matrix (TD TLM), yet more accurate and more capable of modeling a wide variety of frequency-dependent material parameters. In addition, the TFDTLM has proven to have superior dispersion behavior in modeling lossy inhomogeneous media as compared to the TD TLM.