ABSORBING-BOUNDARY CONDITIONS USING PERFECTLY MATCHED-LAYER (PML) TECHNIQUE FOR 3-DIMENSIONAL TLM SIMULATIONS

This paper describes the algorithm that interfaces the three-dimension al (3-D) transmission-line matrix (TLM) with an absorbing-boundary con dition (ABC) based on the perfectly matched-layer (PML) approach, The algorithm uses a coupling between the TLM symmetrical condensed node ( SCN) network and a finite-difference approximation of the PML equation s. Examples are presented in scattering problems and S-parameter chara cterization of discontinuities. Excellent results are found even with absorbing walls located in the region of evanescent waves. Absorption performance obtained are significantly superior to ABC's based on the one-way equation approach and currently used for TLM simulations. Fina lly, it is found that for all tested situations, the algorithm is nume rically stable.