Time-Domain Analysis for Transient Electromagnetic Scattering by Conducting-Dielectric Objects

Transient electromagnetic (EM) scattering by conducting-dielectric objects is formulated by time-domain electric field integral equations (TDEFIEs). The TDEFIEs are usually solved by combining the method of moments (MoM) in space domain and march-on-in-time (MoT) scheme in time domain. The space-domain MoM requires two basis functions to represent the electric and magnetic current densities on material interfaces, respectively, leading to an inconvenience in implementation. Also, the MoT scheme has a late-time instability problem which will aggravate in the surface integral equations with penetrable media. In this work, the TDEFIEs are solved by a different approach in which the Nystrom method is used to discretize the space domain while the Galerkin method with Laguerre basis and testing functions is employed to discretize the time domain. The proposed approach can overcome the defects of conventional approach as demonstrated by a numerical example.