FEM-BEM formulation for the analysis of cavity-backed patch antennas on chiral substrates

An extended variational formulation to study cavity-backed microstrip patch antennas with chiral materials is presented. A finite-element boundary integral numerical approach is applied to satisfy the stationary condition associated with the variational formulation and some features of chiral media for patch antenna applications are investigated. Specifically, an appreciable reduction of the antenna dimensions with respect to the isotropic case and an undesirable increase in the cross-polarization levels are observed.