Wideband Simulations of Periodic Structures by the Hybrid Spectral FDTD/TD-VFz Method

Abstract : The Spectral FDTD (SFDTD) method is combined with the discrete-time time-domain vector fitting algorithm (TDVFz) to analyze 3D periodic structures excited by oblique incident plane waves over a wide frequency band. The time signal reconstruction with TD-VFz produces an untruncated response over an infinite time window allowing an accurate spectral result, specially near the cut-off frequency separating the spectrum propagating wave region of evanescent wave region