Input impedance of probe-fed rectangular microstrip antennas with variable air gap and varying aspect ratio

The input impedance of a rectangular microstrip patch with a variable air gap has been studied theoretically and experimentally. Unlike earlier investigations, the influence of the air gap along with the varying patch width in changing the patch impedance is thoroughly examined. An efficient computer aided design formulation is developed and used for this study, and the computed results are experimentally verified. Superiority of the present theory compared to some earlier models is also indicated.