MOMENT METHOD ANALYSIS OF SIDEWALL INCLINED SLOTS IN RECTANGULAR WAVE-GUIDES

A moment method analysis of sidewall inclined slots in a rectangular waveguide is presented. The main feature is the use of a 90-degrees wedge Green's function to model the external coupling between the parts of the slot in the narrow and broad walls of the waveguide. The aperture field distributions of the inclined slots are solved directly. It is found that for resonant slots, the aperture field is approximately of constant phase, while its amplitude is nearly sinusoidal but with a slight tilt. From the field distribution, various characteristics of the slot can be extracted, such as the conductance, susceptance, and resonant length. The numerical computations are in good agreement with experimental results available in the literature.