High Order Representations for Singular Currents at Corners

Abstract

In connection with a high order method of moments solution of integral equations for electromagnetic scattering, several approaches are investigated for representing current and charge densities in the vicinity of corners. One approach uses the first N terms from the asymptotic solution for an infinite wedge to represent the current density. An alternative approach uses a traditional polynomial type of expansion, but augments it in the vicinity of corners with additional terms from the wedge result. The residual error obtained via the solution of an over-determined system of equations is used to judge the relative accuracy and efficiency of various approaches.