Analysis of coplanar waveguide-fed circular patch antenna

A full-wave analysis of a circular patch antenna fed by an open-ended coplanar waveguide is presented. A set of integral equations are derived by using the Hankel transform and the two-dimensional Fourier transform. Method of moments is applied to solve these integral equations for the current distribution. The surface electric current on the circular patch is expanded by entire domain basis functions, and the surface magnetic currents on the open-ended slot and the coplanar waveguide are expanded by subsectional linear basis functions. Computed results for the reflection coefficient and the input impedance are obtained which compare favorably with measurements.