Mutual admittance characteristics for two-element parallel prolate spheroidal antenna systems

Spheroidal dipole antenna systems consisting of two thin center-fed parallel prolate spheroids in various configuration (side-by-side and collinear) are considered. The resultant EM fields are represented as modal expansions in terms of spheroidal vector eigenfunctions. Translational addition theorems for spheroidal functions play the central role in the formulation of a system matrix which transforms the primary EM excitations of the fed dipoles into their scattered responses. From the knowledge of the system matrix, the mutual admittances of the dipole system are obtained and plotted against center-to-center separation of the dipoles for side-by-side and collinear dipole configurations. The major to minor axial ratios of 10:1 and 100:1 of the prolate spheroidal dipoles are considered for presenting various curves.