Simple and Efficient BZT-Higher-Order PML Formulations for the Metal Plate Buried in Three-Dimensional Dispersive Soil Space Problems

Abstract

Efficient and unsplit-field higher-order PML formulations using the stretched coordinate perfectly matched layer (SC-PML) formulations and the bilinear Z-Transform (BZT) method are presented for truncating the finite-difference time-domain (FDTD) lattices. This method is completely independent of the material properties of the FDTD computational domain and hence can be applied to the modeling of arbitrary media without any modification because of the D-B constitutive relations used. The higher-order PML has the advantages of both the conventional PML and the complex frequency-shifted PML (CFS-PML) in terms of absorbing performances. Two 3D FDTD simulations of the metal plate buried in dispersive soil space FDTD domains have been carried out to validate these formulations. It is shown that the proposed PML formulations with the higher-order scheme are efficient in terms of attenuating both the low- frequency propagating waves and evanescent waves and reducing late-time reflections.