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 aW, 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 aW 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.