Use of Microwave Profiler for Alphasat ALDO In-Orbit Tests and Atmospheric Observations

A radiometer is a wideband receiver that allows the brightness temperature of the troposphere to be measured and the attenuation at any frequency to be inferred very accurately in clear-sky conditions, along with other atmospheric parameters like vapour and liquid water content. In addition to the Communication Ground Station and the Ground Propagation Terminal for the Alphasat Aldo Paraboni (TDP 5) Payload, the Hilmwarte Tower in Graz (Austria) hosts an Atmospheric Propagation and Profiling System (ATPROP): a highly stable microwave radiometer system to assess radio propagation in the spectral range from 10 to 90 GHz. This paper reports on the brightness temperature measurements carried out since August 2013, presenting the experimental setup, the radiometer system characteristics, the attenuation retrieval procedure and the use of the radiometer during the Alphasat Aldo Paraboni (TDP 5) IOT (In-Orbit Tests) in October 2013.