Full-wave analysis of stacked rectangular microstrip antennas

The authors present a full-wave analysis of stacked rectangular microstrip patch antennas. The analysis, which is based on the spectral domain technique, makes use of the electric field integral equation in conjunction with Galerkin´s technique for coverting this equation into a set of linear equations. In the formulation of the problem they assume that the lower patch is excited by an idealised electric current probe. The developed technique is applied to several stacked rectangular patch antennas including to those with two equal patches of accurately aligned edges and of displaced edges. The technique is also applied to investigate the effect of sizes of patches on resonant frequencies, bandwidth and input impedances. Experimental results for the above cases are presented to verify the numerical results