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