Scintillation and simultaneous rain attenuation at 49.5 GHz

Satellite communication systems designed with low power margins need an assessment of the statistical relationship between simultaneous rain attenuation and scintillation. To better use a given system capacity at 20/30 GHz. In the literature the existence or not, on a statistical basis, of this relationship is controversial. Filip and Vilar (1990) assume the statistical independence of the simultaneous rain attenuation and scintillation; Karasawa and Matsudo (1991) conclude that the two phenomena might be treated independently, though they find a weak dependence. On the contrary, Matricciani (1994) suggests that, theoretically, a statistical dependence may exist, a hypothesis supported by experimental evidence from results obtained at 19.77 GHz. The following experimental results at 19.5 GHz seem to confirm that a statistical dependence does exist in particular between the standard deviation of scintillation and rain attenuation, statistically linked by a theoretical power law as found in Matricciani.