The Alphasat satellite was launched on July 25, 2013, and it has two main functions. On one hand, it expands the industrial potential of Inmarsat plc, on the other hand it gives place for four scientific experiments. The purpose of one of these experiments (TDP#5) is to estimate the potential of the usability of Q/V bands. The Department of Broadband Infocommunications and Electromagnetic Theory participates in this experiment. During the semester I was studying the effects of the rain on the level of received power of the unmodulated beacons in Ka/Q band received from the Alphasat satellite, as well as I compared the rain intensity values converted from the attenuation with the values measured by the gauges on the meteorology station on top of the building of the department.
In the first chapter I review in short the technical parameters of Alphasat, as well as the experiments located on the satellite. After this I introduce the station functioning on the department, and I describe the Aldo Paraboni payload in detail.
In the second chapter I review the significance of the rain intensity, as well as the major historical events of the measurement of rain intensity. Following this I describe the rain intensity gauges, in particular the two gauges (drop counter and tipping bucket), that can be found on the department. In the second part of the chapter I write about a great draft of experiments, with the purpose of comparing the rain intensity gauges based on several aspects (e.g. reliability, accuracy).
In the third chapter I review the progress of processing the data collected from the radio and the meteorological station. I touch upon the format of data, as well as the formulas that are necessary for the analysis. Furthermore I show the functioning of the Matlab programs, that are necessary for the data processing, as well as the progress of the attenuation-intensity conversion through a concrete example.
In the fourth chapter I demonstrate and evaluate the values obtained from the above mentioned progress. During the evaluation I review the correlation between the obtained values, and I try to explain the contingent differences. The attenuation and intensity graphs related to the chapter can be found in the appendices.
In the last chapter I rate in short my work performed during the semester, and I touch upon the significance of the rain intensity in the future. I offer a motion for the improvement of the quality of the measurements, as well as for the upgrade of the measurements.