Satellite communications present some significant advantages over terrestrial networks, such as flexibility and reconfigurability of the network, the possibility to establish point-to-multipoint links (broadcasting, mobiles…). Therefore communication satellites need to be integrated with terrestrial networks, and should provide high data rates. To carry such high data rates, higher frequencies should be considered, such as Ka-band (20 GHz - 30 GHz), V-band (40 GHz - 50 GHz) or EHFband (20 GHz - 45 GHz). These offer large bandwidths that are not available at L to Ku band. For some years, innovative satellite systems have been proposed, either in Ka or V band for civil applications (Cyberstar, Euroskyway, Skybridge 2, Skystation, Teledesic, West…) or in EHF band for military applications (ST3SII, GFSatCom, Skynet, Milstar).