Experimental investigations of rectangular, circular and elliptical microstrip patch antennas are reported in this book. An analytical method of controlling the input impedance of different patch antennas as a function of feed location is presented here. Using different kind of reference antennas (rectangular, circular, elliptical) the variation of input impedances, both the real and imaginary components, while changing the feed positions is compared with the theoretical results. At the same time various antenna properties like return loss, input impedance, gain and radiation efficiency are calculated with the proposed model and compared with the simulated results. The results due to different type of patches are compared.