Modeling of arbitrary composite objects with applications to dielectric resonator antennas

A Method of Moments (MoM) technique applied to a Surface Integral Equation (SIE) formulation has been considered for modeling electromagnetic radiation and scattering by an arbitrarily configured composite object of conducting and dielectric bodies. Specifically the SIE is an E-PMCHW formulation which uses the E-field and PMCHW formulations for the conducting and dielectric surfaces, respectively, and RWG (Rao-Wilton-Glisson) basis functions are used to approximate the surface currents. To solve the SIE numerically, the MoM technique using the RWG basis functions has been applied to discretize and transform the integral equations to a system of matrix equation.; The general geometry under consideration may consist of an arbitrary number of conducting and dielectric bodies, which may have arbitrary shapes and form arbitrary junctions. The electromagnetic boundary conditions and continuity of the currents at a junction are rigorously enforced to model the junction properly. A general formalism has been presented for modeling an arbitrary finite 3D composite object employing multi-domain RWG basis functions and systematic descriptions of the geometry. The concept of the Multi-Domain Basis Functions (MDBF) should be useful for other 3D surface basis functions as well as in 2D or BOR (Body of Revolution) formulations.; The implemented FORTRAN code, 3DIE, is a general purpose MoM code suitable for the analysis of the electromagnetic scattering and radiation from an arbitrarily configured composite structure of conducting and dielectric bodies. After extensive validation of the code, several Dielectric Resonator Antennas (DRA) which were not amenable with conventional methods have been analyzed. The computed input impedances and/or far field radiation patterns have been compared with the results computed using FDTD (Finite Difference Time Domain), BOR, and other MoM codes and are in good agreement.