Theories of prolate spheroidal antennas

After reviewing some of the basic properties of spheroidal wave functions, the theory of radiation from a prolate spheroid antenna is considered. Particular attention is given to the complicating influence of a confocal plasma sheath whose properties may be either constant or depend on the polar angle coordinate. The effects of the compressibility of the plasma and the influence of a d-c magnetic field are also considered, using very idealized models. Among other things, it is indicated that a spheroidal structure may be strongly resonated (in a single mode) if the surface impedance has a special form.