Integral-equation-based analysis of transient scattering from periodic perfectly conducting structures

A marching-on-in-time algorithm for solving a time-domain electric field integral equation pertinent to the analysis of plane-wave scattering from doubly periodic, perfectly conducting bodies is presented. For obliquely incident waves, a classically constructed marching-on-in-time solver leads to a non-causal system of equations that requires knowledge of future current values to solve for present ones. Here, time-shifted temporal basis functions and a bandlimited extrapolation procedure that mitigate and eliminate the non-causal nature of the marching-on-in-time system of equations are introduced. The validity and effectiveness of the resulting algorithm are demonstrated through a number of examples.