Ice Crystals and Raindrop Canting Angle Affecting the Interference Performance of a Double-Site Diversity Earth-Space System Employing Frequency Re-Use

Abstract

In current satellite systems operating above 10 GHz the main sources of interference are the differential rain attenuation, as well as the rain cross-polarization (valid for frequency re-use systems). In addition, the ice crystals depolarization along with the raindrop canting angle effects may further degrade the carrier-to-interference ratio and this is more obvious for systems operating under the circular incident polarization. In the present paper, an existing method to predict the degradation of the (C/I) ratio due to all the above reasons, valid for single-site systems, is properly modified to include double-site interfered systems, employing frequency re-use. Another important point of the paper is the derivation of a set of simple regression formulas, appropriate for use by the system designer for back of the envelope computations. Finally, the difference between simulated results, derived after taking into account or not the ice crystals and raindrop canting angle effects, for various frequencies and polarization angles, is examined. Some useful conclusions are deduced.