High-Performance Wideband Double-Ridged Waveguide OMT for the 275–500 GHz Band

In this article, a high-performance wideband double-ridged waveguide orthomode transducer (OMT) for the 275-500 GHz band has been designed, fabricated, and tested. Such wideband performance would allow to cover two full RF bands in radio astronomy, 275-373 GHz and 385-500 GHz, with a single receiver, allowing for additional science cases and simplified operations. Successful fabrication of prototypes by direct machining in two split blocks and successful testing prove the readiness for complex fabrication of OMT components in this frequency range. The reported performance of our prototype OMT is to our knowledge the best at sub-mm wavelengths over such as wide bandwidth.