Moment Method Solutions for Polarization Agile Slots in Bifurcated Waveguide

ABSTRACT Computational models, based on the moment method, are described for non-rectangular slots in both the broad and side walls, respectively, of E-plane and H-plane bifurcated waveguides. These slots permit the realisation of polarisation agility in slotted-waveguide array antennas. The slots, which are generally T-shaped, display a three dimensional form and this introduces an additional level of complexity into the formulation of a moment method solution for the electromagnetic boundary value problem represented by the slot. The steps introduced to accommodate this problem are described. Computational results for some of the slot geometries examined are presented and these are shown to be in broad agreement with measured values.