Application of the Singularity Expansion Method to Scattering From Imperfectly Conducting Bodies and Perfectly Conducting Bodies Within a Parallel Plate Region.

Abstract : This note is a continuation of previous work on the singularity expansion method. Different integral-equation formulations describing electromagnetic scattering from imperfectly conducting bodies are considered. A set of volume surface integral equations is used to determine the analytical properties in the complex frequency plane of the field scattered from imperfectly conducting, finite bodies. Conditions are determined for the constitutive parameters of the scattering body so that the scattered field can be described only by damped sinusoidal oscillations when the incident field is a delta function plane wave. Scattering from a perfectly conducting, finite body within a parallel plate region is also considered. It is shown that the singularities in the complex frequency plane of the scattered field are poles and branch cuts. The locations of the branch cuts depend only on the separation between the parallel plates. (Author)