System implications of rain and ice depolarisation in Ka-band satellite communications

This paper investigates the impact of rain and ice depolarisation on the performance of satellite communications systems operating in the Ka-band with orthogonal polarisations. Various prediction methods for evaluating the degradation of dual-polarised system availability due to rain and ice are reviewed. Their results are compared using depolarisation data and statistics collected in Belgium at 20 GHz during the ESA's Olympus satellite experiment and exhibit significant discrepancies. A procedure based on the combined use of experimental data and of a simulation software for communications systems confirms the prediction produced by one method. The proposed procedure also yields estimation of system quality during particular depolarisation events.