Time Domain Hybrid Method for the Coupling Analysis of Transmission Lines in Shielded Enclosure Excited by Leakage EM Fields

Abstract

This paper presents an efficient time domain hybrid method, consisting of thin wire finite-difference time-domain (FDTD) method, transmission line (TL) equations, interpolation schemes and an auto mesh generator technique, which can be well applied for the coupling problem of transmission lines in shielded enclosure excited by leakage electromagnetic (EM) fields created by some sensitive circuits. In this method, the radiation of these leakage EM fields are simulated by the thin wire FDTD method with auto mesh generation technique firstly. Then the TL equations combined with interpolation schemes are utilized to construct the coupling model of multi-conductor transmission lines (MTLs) excited by these leakage EM fields. Finally, the TL equations are solved by the difference scheme of FDTD to obtain the voltages and currents on the MTLs and terminal loads. The significant feature of this hybrid method is that it can realize the co-simulation of space EM field radiation and transient responses on the MTLs. The accuracy and efficiency of this presented method are verified via the numerical simulation of multi-conductor transmission lines excited by these leakage EM fields in a shielded enclosure by comparing with the FDTD method.