Patch antennas loaded by inhomogeneous substrates: a combined spectral domain - genetic algorithm approach

The optimized design of patch antennas with inhomogeneous loading materials is presented in this letter. The analysis and a first coarse design of the antennas is demanded to a numerical tool based on the Method of Moments (MoM) and on a full-wave formulation developed in the spectral domain that exploits both rigorous and asymptotic closed form expressions of the Green's function of a stratified integrated structure with inhomogeneous substrates. In order to match the specific prescribed requirements for the antennas, then, the optimization of the patch shape (fine design) is performed by a dedicated subroutine implementing the genetic algorithm search and integrated in the aforementioned MoM numerical tool. Some numerical results showing the capabilities of the code are finally presented.