Microstrip antenna on a spherical surface. A new formulation of the problem

A new efficient and accurate method of analysis of the circular microstrip patch antenna on spherical surfaces, that permit analysis of the arrays of such elements, is presented. Viewing space as a spherical waveguide, the circular microstrip antenna performance analysis is viewed as a spherical waveguide junction discontinuity problem and solved. Fields in the substrate as well as the exterior region exterior to the spherical surface is expended in terms of spherical waveguide modes and the current on the circular patch is expended in terms of circular cylindrical eigen waveguide modes. Enforcing all the boundary conditions, the far zone broadside radiated field expression is derived. Numerical computation of this field provides the patch resonant frequency. The role of creeping waves in the substrate region is stated.