Analysis on the Causes of the Decrease of Transmitting Polarization Isolation of Shipborne Satellite Communication Antenna

In order to analyze the reasons for the decrease in the transmission polarization isolation of the shipborne satellite antenna, the reasons for the decrease in the polarization isolation were explored in terms of the antenna's three-axis architecture and the circular polarizer of the feed system. First, the definition and test method of polarization isolation are introduced, and then the different polarization modes of electromagnetic waves are expressed by mathematical formulas. On this basis, the polarization angle error caused by the tracking of the antenna three-axis architecture and the inaccurate position of the limit switch of the circular polarizer are analyzed, and the polarization isolation is reduced. The actual results are used to verify that the C-axis introduces the opposite polarization. Finally, countermeasures were proposed for the impact of isolation.