An improved prediction method for rain attenuation in satellite communications operating at 10-20 GHz

Several prediction methods for rain attenuation presented so far are evaluated using a common long-term data base (total 124 sets of measurements) for oblique propagation paths with frequencies of from 10 to 20 GHz, and an improved prediction method reflecting the evaluation results performed is proposed. The evaluation results indicate that CCIR methods give relatively high precision, although in this respect, there is not such a great difference from other methods. The method proposed here includes a rain area size parameter as a function of rain rate for 0.01% of the time so as to minimize the prediction error. It is verified that the method thus obtained gives the best precision, at the present time, for predicting rain attenuation on Earth-to-space propagation paths at 10–20 GHz.