Advanced computer design for a high performance compact ortho-mode transducer

We present a compact-size, high-performance, single-branched ortho-mode transducer (OMT), operating in the 17-18.5 GHz frequency band designed and optimized entirely at the computer level. We have used an hybrid approach which employs both the mode-matching technique (generalized scattering matrix) and an integral equation approach (admittance type representations). This hybrid approach not only provide increased confidence with the computed response by checking the results obtained with the two different techniques, but also allows the designer to optimize part of the structure with one technique and part with the other, thus enhancing flexibility, efficiency and reliability of the final design. The OMT has been designed, fabricated, measured and, due to its very satisfactory performance, subsequently included in a compact range in order to test the transmit and receive circuitry of satellites operating within the specified frequency band.