PERFECTLY MATCHED LAYER AND PIECEWISE-LINEAR RECURSIVE CONVOLUTION FOR THE FDTD SOLUTION OF THE 3D DISPERSIVE HALF-SPACE PROBLEM

A 3D finite-difference time-domain simulation of a dispersive, inhomog eneous half-space problem is described. The formulation uses the perfe ctly matched layer (PML) absorbing boundary condition (ABC) extended t o dispersive media. The dispersion is characterized by a two-species D ebye model with parameters taken from reported experimental data of so ils with different moisture contents. The time-stepping scheme for the electric field uses the piecewise-linear recursive convolution (PLRC) method, For homogeneous half-space problems, the simulation results a re compared against results from numerical integration of Sommerfeld-t ype integrals. To illustrate its applications, the inhomogeneous half- space simulations include results from the ground penetrating radar si mulated response of buried objects in realistic soils.