Radiation and scattering from planar microstrip structures of arbitrary shape

Summary form only given. A space-domain approach based on the mixed-potential integral equation formulation is applied to the computation of electromagnetic fields radiated and scattered by planar microstrip structures having arbitrary or irregular shapes. The effects of the substrate are rigorously incorporated in the analysis by means of the vector and scalar potential Green´s functions. The current distribution induced on the conducting patch is approximated in terms of vector basis functions defined over triangular elements. Once the current expansion coefficients are computed by the method of moments, the far zone fields are easily found by the stationary phase method, and are given in terms of the Fourier-transformed basis functions and the transmission line voltages evaluated at the stationary point values of the spectral variables. Current distributions, radiation patterns, and RCS (radar cross section) results have been computed for several microstrip patch antennas of various shapes.<>