Compact septum polarizers with a circular output waveguide

Septum polarizers (SPs), built on a square waveguide with stepped ridged waveguide junctions, have found many applications in antenna systems and polarization measurement equipments. In the present paper, the features of the developed CAD of compact square-waveguide SP´s with a circular output waveguide and results of its design application are discussed. The SP configurations under consideration are combined by the following components: rectangular-to-rectangular, bifurcated square-to-ridged, ridged-to-ridged, square-to-square, and square-to-circular waveguide junctions. Exact numerical models for all the components are built on the mode-matching technique. The eigen-value problem for the single-ridged waveguide is solved using the moment method with basis and tested functions taking into account the field behavior near edges.