Time-Domain Integral Equation Analysis of Electromagnetic Coupling through an Aperture Into a Parallel-Plate Waveguide Filled With a Lossy and Dispersive Dielectric

This paper proposes an efficient time-domain method to solve the method-of-moments-formulated integral equation pertinent to electromagnetic coupling through an aperture into a parallel plate waveguide (PPW) filled with a lossy and dispersive dielectric. The proposed method utilizes a fast Fourier transform-accelerated marching-on-in-time algorithm as a solution framework. Appropriate numerical procedures are introduced to avoid the adverse numerical effects associated with frequency-domain windowing and time-domain aliasing when convolving the time-domain Green's function of PPW with the derivative and integral of the respective temporal basis functions. The accuracy of the proposed method is confirmed by comparing the results of a circular, multiple square-shape apertures and a square aperture with those obtained using a commercial finite integration technique and a frequency-domain solver.