Preliminary Results from the ASI and NASA Alphasat Experimental Equipment

Near future broadband satellite communication systems will aim at providing extremely high capacity and very high data rates as requested by the current market both for broadcast and multimedia applications. This objective is driving the adoption of higher carrier frequencies in the Ka or Q/V bands and beyond. Due to the steep increase in the impairments caused by the atmosphere, the design of communication systems must rely on the extensive use of Fade Mitigation Techniques (FMT), among them the site diversity will be considered. In this scenario, the Alphasat Aldo Paraboni propagation experiment has been conceived and supported by the Italian Space Agency (ASI) (and executed by the European Space Agency) to ease the shift of commercial satellite-based systems to higher frequencies, using two beacons at 19.701 (Ka band) and 39.402 GHz (Q band). This contribution addresses the preliminary results obtained in the framework of the Alphasat propagation experiment from the ASI equipment, deployed at Spino d'Adda and from the NASA equipment, hosted at the Dipartimento di Elettronica, Informazione e Bioningengeria of Politecnico di Milano. The paper will present initial statistics (for an observation period of 6 months) of the signal attenuation measured at these two sites and will provide some examples on the effectiveness of mid-scale site diversity, i.e. considering the stations in Spino d'Adda and Milan (approximately 23 km apart).