Limitations of the ITU-R P.838-3 model for rain specific attenuation

The International Telecommunication Union (ITU) recommendation P.838-3 provides a method to calculate the specific attenuation due to rain. Although the model nature is twofold, to hold a physical basis and to maximize the accordance with experimental data, its current implementation comes with some limitations and inaccuracies. In this contribution we highlight some differences observed when a physically based attenuation model is built and used for comparison. Some nonphysical behaviors of the ITU model are spotted with the variation of rain rate, polarization and elevation angle in a significant frequency range for satellite communication links.