Scattering from a cavity backed microstrip antenna on a bi-anisotropic substrate with a finite ground plane by a hybrid finite element method

A new extended finite element formulation for finding radiation patterns, radar cross section (RCS) and input impedance of planar integrated circuits on a very general bi-anisotropic grounded slab with finite size is presented. The approach is based on a hybrid finite element method (FEM) wherein the electromagnetic fields in the FEM region are coupled to the fields outside by a surface integral equation. Because of the local nature of the FEM, this formalism allows inclusion of the inhomogeneities in the problem domain. Numerical results are compared and agree well with existing published data for various conventional configurations.