Satelite Communication Systems - State of the Art and Develpment Trends

In connection with the present development trends of the technology, and with the subsequent service rendering capability, the role of communication satellites in future is discussed. Three basic types of systems are considered: - for Mobile communications - for Point-to-Multipoint Fixed Communications - for Point-to-Point Fixed Communications The emphasis is put on point-to-point systems, which marked the beginning of satellite communications; for these systems it is easier to predict future developments. The use of frequency bands below 15 GHz will propably cover all requirements coming from Intelsat and from emerging countries. In the case of regional or domestic systems for highly developed countries, such as the U.S.A. and Europe, the local constraints will probably impose the use of the 2030 GHz bands, which would allow installing the Earth terminals close to traffic centers, with dramatic reduction in channel costs. Key features of these systems should be: - use of well stabilized platform with multibeam antennas - TDMA with switching onboard - Voice Signals Processing - Space Diversity, where needed