The methodologies for the Attenuation prediction models due to rain attenuation in frequencies above 10 GHz can be separated by utilization of the input data. The methods based in measurement and experimental data. The last one method is founded on databases from automatic meteorological stations located in different climatic zones within given geographical zone.

One of the most used method using empiric data it is based in ITU logical process. This methodology has the technical name of ITU-R P.618 Recommendation: "Propagation data and prediction methods required for the design of Earth-space telecommunication systems".

As is mentioned this Recommendation, it is extremely important that the methods for the propagation prediction parameters demonstrate in Recommendation P.618 be imported for planning Earth-space links in frequencies above to 10 GHz [1]. Following the regards above, the process to computation of long-term rain attenuation statistics from point rainfall rate is next developed.