COMPLEX MULTIPOLE-BEAM APPROACH TO 3-DIMENSIONAL ELECTROMAGNETIC SCATTERING PROBLEMS

A novel approach to reducing the matrix size associated with the metho d-of-moments solution of the problem of electromagnetic scattering fro m arbitrarily shaped closed bodies is presented. The key step in this approach is to represent the scattered field in terms of a series of b eams that are produced by multipole sources located in a complex space . On the scatterer boundary the fields that are generated by these mul tipole sources resemble the Gabor basis functions. By utilizing the pr operties of the Gabor series, guidelines for selecting the orders as w ell as the locations of the multipole sources are developed. The prese nt approach not only reduces the number of unknowns but also generates a generalized impedance matrix with a banded structure. We verify the accuracy of the proposed method by using internal accuracy checks and by comparing the numerical results with the analytic solution for a s pherical scatterer.