C-band orthomode transducer for compact and broadband antenna feeders

The design and evaluation of a compact C-band orthomode transducer for dual polarisation satellite communications is presented, covering the bands 3.7-4.2 GHz and 5.925-6.425 GHz (54% of fractional bandwidth separation). Over such a broadband, the main difficulty is to obtain a compact structure able to fulfil the stringent satellite specifications with minimum longitudinal length. The proposed configuration, validated with a tested prototype, also reduces the number of connections and parts in the fabrication, decreasing the passive intermodulation risk and the mass and volume.