Analysis of transient electromagnetic scattering phenomena using a two-level plane wave time-domain algorithm

A fast algorithm is presented for solving electric, magnetic, and combined field time-domain integral equations pertinent to the analysis of surface s cattering phenomena. The proposed two-level plane wave time-domain (PWTD) a lgorithm permits a numerically rigorous reconstruction of transient near fi elds from their far-held expansion and augments classical marching-on in-ti me (MOT) based solvers. The computational cost of analyzing surface scatter ing phenomena using PWTD-enhanced MOT schemes scales as O(NtNs3/2 log N-s) as opposed to O(NtNs2) for classical MOT methods, where N-t and N-s are the numbers of temporal and spatial basis functions discretizing the scatterer current. Numerical results that demonstrate the efficacy of the proposed s olver in analyzing transient scattering from electrically large structures and that confirm the above complexity estimate are presented.