The Italsat satellite was launched from Kurou (French Guyana) at the beginning of 1991. The project originated from a proposal of the Prof. Francesco Carassa, who first understood the importance of the millimetric waves for the future of the satellite-based wide-band telecommunications. Italsat allowed the most advanced propagation experiments ever seen, and produced, during its 10-year life under the responsibility of the Politecnico di Milano, an unequalled propagation data-base up to the 50 GHz frequency band. Besides the advanced radiopropagation experiments, Italsat also set a milestone in the history of the satellite telecommunications because it allowed to test advanced technologies, for that time, such as on-board digital processing and signal routing through the beam-exchange technique.