A Differential Technique for Detections of Circularly Polarized Satellite Signal Parameters

This paper presents fundamental concepts, operational principles, and typical experimental results of a differential technique for detections of circularly polarized satellite signal parameters at low axial ratios. The approach is to equip a rotating π-polarizer with an orthomode transducer in the antenna front end. A two-channel phase-locked receiver is used to detect the differential phase (DP) and the differential level (DL) between the two output channels. The required parameters are then readily available from the displays of the DP and DL values on a strip chart recorder.