ORTHO-MODE TRANSDUCERS FOR MULTI-FEED RECEIVERS

This paper presents a novel configuration of ortho-mode transducers that is suitable for multi-feed receivers to be used in correlation radiometers with very high sensitivity aimed at cosmological and earth observations. In particular, the design, manufacturing and testing of the 49 Q-band ortho-mode transducers of the Large Scale Polarization Explorer will be reported. The latter is a balloon-based experiment funded by the Italian Space Agency aimed at the measurement of the Cosmic Microwave Background polarization state at large angular scales. The ortho-mode transducers configuration has been conceived toward a high parallelization rate of the manufacturing process, while meeting the high electromagnetic specifications set by the application (i.e., cross-coupling < -50 dB, isolation > 50 dB).