Optimized Entire-Domain Moment-Method Analysis of 3d Dielectric Scatterers

When compared with commonly used subdomain moment-method analysis, entire-domain analysis of 3D dielectric scatterers results in a greatly reduced number of unknowns. Unfortunately, the expressions for matrix elements tend to be quite complicated and their calculation extremely time-consuming if evaluated directly. It is shown in the paper that, in a Galerkin-type solution with large trilinear hexahedral basic volume elements and three-dimensional polynomial approximation of volume current inside them, these expressions can be manipulated analytically for optimized rapid non-redundant integration. Consequently, a method for the analysis of 3D dielectric scatterers is obtained that is efficient, rapidly converging with increasing degree of approximation for current, remarkably accurate and very moderate in computer memory requirements. The applicability of the method of moments is thereby extended to bodies of electrical sizes greatly exceeding those that can be dealt with by subdomain methods.