Variational analysis of inclined slots in the narrow wall of arectangular waveguide

A variational analysis for calculating the admittance of the inclined slots in the narrow wall of a rectangular waveguide is presented. The analysis uses the 90° wedge Green's function to model the scatterings off the waveguide corners and assumes an equiphase half-cosinusoidal electric field distribution along the slot aperture. Based on these, a variational equation is derived for the reflection coefficient due to the slot discontinuity, from which the slot admittance is calculated. Through comparisons between the computed results and the literature results, the analysis is found to be accurate, reliable, and efficient