Multiyear Second Order Statistics of ALPHASAT Beacon Measurements at ASI Ground Stations

The Alphasat Aldo Paraboni experiment by the Italian Space Agency measures signal attenuation at 19.701 GHz and 39.402 GHz using beacon signals from a geosynchronous satellite to ground stations in Tito Scalo and Spino d'Adda, Italy. Second order statistics on data collected from 2015 to 2023 are presented, supporting the understanding that higher frequencies, as seen with the 39.4 GHz beacon, are more susceptible to atmospheric fading, exhibiting higher fade percentages, steeper fade slopes, and more frequent long-duration fades. Comparisons of the measurements statistics with Rec. ITU-R P.1623-1 models show expected discrepancies, with the ITU-R models underestimating fade percentages and counts while overestimating fade slope probabilities. These findings emphasize the importance of experimental campaigns and the opportunity to further refine predictive models.