Large-domain integral-equation method for analysis of general 3-D electromagnetic structures

A highly efficient, PC-oriented large-domain method is proposed for the analysis and CAD of a wide class of complex 3-D electromagnetic structures. The structures can be any combination of dielectric bodies, conducting surfaces and wires. The bodies are approximated by trilinear hexahedrons (distorted bricks), the surfaces by bilinear quadrilaterals (distorted rectangles) and the wires by straight-wire segments. Current distribution in the elements is approximated by high-order polynomials in local parametric co-ordinates, enabling electrically large elements. All elements can have any distributed impedance loading. In addition, the structure can have lumped loadings and generators of several kinds. The unknown current-distribution coefficients are determined by a Galerkin-type solution of a system of coupled integral equations. The principal advantage of the proposed method over existing methods is its generality combined with a comparatively small number of unknowns required for a given problem. The accuracy and versatility of the method are illustrated by a number of examples where analytical or experimental results are available.