Correlation between attenuation of 20 GHz satellite communication link and Liquid Water Content in the atmosphere

摘要

The effect of Liquid Water Content, i.e. the mass of the water per volume unit of the atmosphere, on the attenuation of a 20 GHz communication link between a ground antenna and communication satellite is tackled in this paper. The wavelength of 20 GHz electromagnetic radiation is comparable to the droplet size, consequently the scattering plays an important role in the attenuation. To better understand this phenomenon a correlation between measured LWC and attenuation is analysed. The LWC is usually estimated from the pluviograph rain rate measurements that captures only spatially localized and ground level information about the LWC. In this paper the LWC is extracted also from the reflectivity measurements provided by a 5.6 GHz weather radar situated in Lisca, Slovenia. The radar measures reflectivity in 3D and therefore a precise spatial dependency of LWC along the communication link is considered. The attenuation is measured with an in-house receiver Ljubljana Station SatProSi 1 that communicates with a geostationary communication satellite ASTRA 3B on the 20 GHz band.