The boundary value solution of electromagnetic radiation from an axis-asymmetric slot antenna on a perfectly conducting prolate spheroid coated with a confocal sheath is presented. The electromagnetic fields are expanded in terms of prolate spheroidal vector wave functions. The unknown expansion coefficients are determined from a set of linear equations derived from the application of boundary conditions on the tangential fields' components. Numerical results for radiation patterns and power are presented. It is found that the thickness of the sheath has a significant effect on the radiated fields, and the radiated power is greatly enhanced for certain values of the sheath thickness.
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