Superstrate effect on the resonant frequency of microstrip antennas

A computer code based on the full‐wave analysis and the spectral domain approach was developed to predict the effect of superstates on the resonant frequency of rectangular microstrip antennas. The formulation is based on the method of moments using Galerkin technique with entire‐domain basis functions. The resonant frequency is calculated by using an optimization routine that searches for the stationary condition of the characteristic equation. Numerical solutions are obtained for some test cases and are verified by comparison with experimental results.