Extended Least Squares Iterative Techniques in the Solution of Electromagnetic Scattering by Penetrable Objects

Abstract

The iterative computation of frequency-domain electromagnetic fields scattered by arbitrarily shaped, inhomogeneous, penetrable objects is investigated. A domain-type integral equation is solved by minimizing iteratively a global root-mean-square error. Starting with an arbitrarily chosen initial estimate and employing different variational functions, a general, flexible, iterative procedure is developed in which a monotonic decrease in the error is enforced in each iteration step. Different iterative schemes are obtained by employing different, suitable variational functions. Several typical schemes are compared numerically and numerical results are presented for one- and two-dimensional scattering problems. In the latter both TE- and TM-problems are investigated.