Efficient Calculation of Cloud Attenuation for Earth–Space Applications

This letter presents a simple and accurate approach to calculate cloud attenuation for Earth-space communication systems operating in the 20-200-GHz frequency range. The methodology relies on the use of the mass absorption coefficient for liquid water a_W, which is assumed to be independent of the site of interest. This finding, inferred from an extensive set of radiosonde observations collected in 14 locations throughout Europe, allows to devise a simple expression for a_W as function only of frequency and, consequently, to efficiently calculate cloud attenuation. This indeed represents the main advantage of the approach, which, as a result, can take full advantage of global datasets of integrated liquid water content W made available, for example, by Earth Observation sensors.