Characteristic mode analysis of a slot in a conducting plane separating different media

The authors analyze a slot in a conducting plane separating different media when the slot is illuminated by a transverse electric and a transverse magnetic plane wave. The general characteristic mode theory for different media is used for the solution of this problem. The characteristic modes, which are computed using the method of moments, provide numerical results for the characteristic currents, the equivalent magnetic currents, and the field pattern for a slot whose width is a function of the wavelength. Analytical expressions for the narrow slot are also given