COMPLEX MULTIPOLE BEAM APPROACH TO ELECTROMAGNETIC SCATTERING PROBLEMS

A novel approach to reducing the matrix size associated with the Metho d of Moments (MoM) solution of the problem of electromagnetic scatteri ng from arbitrary shaped closed bodies is presented in this paper. The key step in this approach is to represent the scattered field in term s of a series of beams produced by multipole sources located in a comp lex space. On the scatterer boundary, the fields generated by these mu ltipole sources resemble the Gabor basis functions. By utilizing the p roperties of the Gabor series, guidelines for selecting the orders as well as locations of the multipole sources are developed. It is shown that the present approach not only reduces the number of unknowns, but also generates a generalized impedance matrix with a banded structure and a low condition number. The accuracy of the proposed method is ve rified by comparing the numerical results with those derived by using the method of moments.