Marconi’s last experiences on radio relay links and their impact for the successive development of the Italian Terrestrial and Space Microwave Telecomunications System

This paper is aimed to outline how Guglielmo Marconi’s studies on the applications of ultrashort wavelength radio propagation from the beginning of the ‘30s of XX century after the second world war. Of main concern was the experiment promoted by G. Marconi and carried out on board “Elettra” yacht in 1932, to demonstrate thefeasibility of a 270 Km microwave radio link Monte Cavo-Golfo Aranci between Monte Cavo (near Rome) and Golfo Aranci (Sardinia). To such event were attending several authorities representing Italian institutions, in particular Giuseppe Pession and Algeri Marino, that successively promoted between 1936 and 1940 a telephone radio link of more than 500 Km to connect Milano and Rome. The realization of this work was commissioned to the Fabbrica Italiana Magneti Marelli (FIMM) laboratories, with the cooperation of the aeronautical radio communication engineering personnel. This, and other initiatives promoted by G. Marconi before his death in 1937, can be considered as the initial steps towards the development in Italy of a postwar telecommunications industry, mainly based on the exploitation of microwave radio communication techniques.