Accurate CAD model for the analysis of microstrip Antennas of various form with a dielectric cover

We present an accurate analytical model for the determination of the electrical characteristics (resonant frequency, input impedance) of probe fed microstrip antennas with a dielectric cover. This model is based on a modified Wolff model using a variational definition of the surface charge density in order to take various shapes of the radiating element (square, rectangle, disc, triangle, ...) into account. The input impedance is calculated from an equivalent circuit with a rigorous probe model. Theoretical and experimental results are successfully compared for different patch forms and various thickness of the dielectric cover.