Modified Combined Field Integral Equations for Electromagnetic Scattering

Abstract

The boundary integral formulation of exterior boundary value problems for the Maxwell system may not be equivalent to the original uniquely solvable problem if the wave number corresponds to an eigenvalue of an associated interior eigenvalue problem. To avoid these spurious modes one may use a combined boundary integral approach. To analyze the resulting boundary integral equations in the energy function spaces suitable regularizations have to be introduced. Here we formulate and analyze a modified boundary integral equation which is based on the use of standard boundary integral operators only. A first numerical example shows the applicability of the proposed approach.