Exact dipole radiation for an oblate spheroidal cavity filled with isorefractive material and aperture-coupled to a half space

An oblate semi-spheroidal cavity flush-mounted under a metal plane and coupled to the half-space above it via its circular interfocal aperture is considered. The cavity is filled with a material isorefractive to the medium that occupies the half-space above it. An exact solution is obtained for the radiation of an electric or magnetic dipole located on the symmetry axis of the structure, either outside or inside the cavity, and axially oriented. Numerical results are provided.