SS-FDMA channelization and routing in advanced multibeam mobile satellite systems

Resumes the investigations carried out in the frame of INMARSAT Contract INM/86-218/HK: `Study of Channelization and Routing in an INMARSAT 3rd Generation Satellite Transponder´ dealing with the design of a satellite-switched frequency division multiple access (SS-FDMA) onboard router for multibeam mobile satellite systems of next decade (1991 technology has been taken as a reference). SS-FDMA is basically an adaptation of FDMA to multibeam satellite systems, re-proposed in the early 1980s as a consequence of significant breakthroughs achieved in the field of HPA linearization-to reduce multicarrier intermodulation and thus the amount of required backoff-and forward error correction (FEC) codecs implementation, necessary to balance link budget deficiencies in the presence of small (low-cost) terminals. A number of technology issues are present in such user-oriented systems, including narrowband filtering, large switching matrices and low phase noise programmable mixers. They are discussed and limitations/emerging trends indicated