Ultra-broadband low axial ratio corrugated quad-ridge polarizer

The design and fabrication of an ultra broadband square quad-ridge polarizer is discussed here. The principal advantages of this topology relay on both the instantaneous bandwidth and the axial ratio improvement. Experimental measurements exhibit very good agreement with the predicted results given by mode matching techniques. The structure provides an extremely flat axial ratio (AR <; 0.4 dB) and good return losses >25 dB at both square ports over the extended Ku band (≈ 60%). Moreover, yield analysis and scaling properties demonstrate the robustness of this design against fabrication tolerances.