Statistical results on centimetric wave propagation after two years of activity with the Italian satellite Sirio

The main statistical results obtained through Sirio after two years of activity are described. They concern absolute attenuation at 11.6 and 17.8 GHz, and differential attenuation over a bandwidth of 500 MHz centered around 11.6 GHz. Long-term statistical relationships between the attenuation at the various frequencies, and fade duration and gradients, are presented. Preliminary rain-intensity measurements collected at the same sites are also reported in order to assess the climatological effects of the different locations in which data have been collected.