Explicit Conditions for Virtual Boundaries in Initial Boundary Value Problems in the Theory of Wave Scattering

Abstract

This paper deals with the problem of finding a correct way of restricting the computational domain in the FDTD-method in its application to the analysis of transient wave processes in infinite homogeneous regions containing compact inhomogeneities. The formulation of the explicit ABCs (Absorbing Boundary Conditions) in such a way that they do not distort the physical model simulated by the mathematics, and the incorporation of these ABCs in the computational scheme form the basis of the approach presented here. A number of numerical results are given, illustrating in particular the performance of the exact ABCs in comparison with lower order approximations.