A rigorous analysis of weakly excited broadwall slots

Conventional slot models based on simplified boundary element or finite element analysis have been found to yield poor solutions for weakly excited coupling or radiating slots. The longitudinal component of the aperture electric field has been found to be significant in a weakly excited slot even when the slot is narrow. An improved scattering model, proposed for weak slots with the conventional boundary element analysis and a correction term obtained from experiment, was found to be good. The pulse basis functions employed previously by Peterson, Espino and Rengarajan (see Electronics Lett., vol.28, no.1O, p.909-911, 1992) do not model the aperture electric field adequately, thus resulting in large errors in the boundary condition for the aperture magnetic field. Such errors affect the overall solution for the aperture electric field and the scattering parameters of the weak slot. We demonstrate a rigorous and accurate solution for the weak slot with the use of entire domain polynomial basis functions for both components of the aperture electric field in the Galerkin method.<>