Improved scaling factor for long-term rain attenuation statistics as a function of link elevation

The attenuation due to rain is one of the main impairments in satellite communications. It is well known that rain attenuation is dependent on the elevation angle of the link, being more severe at low elevation angles; this has a definite impact on the design of TLC and data download systems based on low earth orbit (LEO) satellites. As measurements at various elevation angles are seldom available, it is necessary to use prediction and scaling models. This paper presents a simple model to scale long-term rain attenuation statistics as a function of link elevation angle. The model receives as input the known complementary cumulative distribution (CCDF) at a specific elevation and generates the CCDF scaled at other elevation angles.