On combining attenuation statistics of different tropospheric effects affecting EHF earth-space links

Three attenuation statistics combination methods are evaluated and compared in this contribution for the first time using a consistent set of propagation data used as input and as a reference to test the methods' performance. The three approaches, which rely upon different statistical assumptions, aim at estimating the total tropospheric attenuation statistics by combining the complementary cumulative distribution functions of the attenuation associated to the different tropospheric impairments, namely clouds, gases, rain, and scintillations. The prediction performance tests are conducted, using as reference, the propagation data (19.7 and 39.4 GHz) collected in Milan, Italy, in the framework of the Alphasat Aldo Paraboni propagation experiment during 2017 and 2018. Results indicate that the combination method included in the inforce recommendation ITU-R P.618-13 provides the highest performance at both bands.