Finite Element Method for Solving Electromagnetic Scattering Problems.

摘要

One of the major issues associated with using the finite element method in opening regions is the problem of truncating the computational mesh. There have been numerous techniques which have been developed in the past several years. Hybrid finite element methods were first introduced by Silvester and Hsieh and McDonald and Wexler. They used a surface integral equation involving the appropriate Green's function that satisfies Sommerfeld's radiation condition at infinity to account for the truncation at the boundary. Mei developed an innovative method called the unimoment method that utilizes finite-element solutions inside a sphere containing the scatterer and eigenfunction expansions in the exterior of the sphere to compute the fields everywhere. Since then, several modifications and/or extensions of the aforementioned methods have appeared. In this paper, we present a new finite element formulation of the electromagnetic scattering problem. This new formulation could be thought of as a generalization of the unimoment method. Although our preliminary results are for two dimensional problems, the method can be extended to three dimensional geometries. 7 refs., 2 figs.