Characteristic modes of a rectangular aperture in a perfectly conducting plane

The objective of the paper is the analysis of a rectangular aperture in a perfectly conducting plane using the characteristic mode theory. The problem is first formulated as an operator equation involving the continuity of the tangential components of the magnetic field in the aperture region. The operator equation is used, with the help of the moment method, to determine the eigenvalues, eigencurrents, and the characteristic magnetic currents of the aperture. When these modes are determined, the equivalent magnetic current and other parameters of interest can then be obtained.<
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