Equivalent circuit model for the time-domain analysis of multiconductor transmission lines by the implicit FDTD method

In EMC studies, the understanding of the electromagnetic couplings in MTL (multiconductor transmission lines) is very important. The FDTD (finite difference time domain) method has been known as one of important techniques for analyzing MTL. We propose a new FDTD method based on implicit difference approximation rather than the explicit approximation in the conventional FDTD method. A circuit model is derived and generalized to easily accommodate arbitrary circuits at both the source and load termination. The proposed implicit FDTD method may be superior to the conventional FDTD method in terms of generality and robustness of the algorithm.