Rain attenuation is very dependent and related to the frequency that is being used in satellite communications. for example , the downlink frequency of C band at 4 GHz, the
attenuation of clear sky condition is only about .5dB. problems will occur when going frequency more than 10 GHz. At Ku band (10-18 GHz), the attenuation is less than 1 dB in clear weather. But when in raining weather, the attenuations can high up to 10 dB.