Aperture excitation of a wire in a cavity

In this work, the problem of determining the currents excited on a wire enclosed within a rectangular cavity is considered. The wire and cavity interior are excited by electromagnetic sources exte­ rior to the cavity which couple to the cavity interior through a small aperture in the cavity wall. It is assumed that the wire is thin, straight and oriented perpendicular to one of the cavity walls. An integral equation is formulated for the problem in the frequency domain using equivalent dipole moments to approximate the effects of the aperture. This integral equation is then solved numer­ ically by the method of moments. The dyadic Green's functions for this problem are difficult to compute numerically; consequently extensive numerical analysis is necessary to render the solution tractable. Sample numerical results are presented for representative configura­ tions of cavity, wire and aperture, and suggestions for future exten­ sions of this work are discussed.

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