DESIGN OPTIONS FOR FUTURE COMMUNICATIONS SATELLITES

Abstract

The INTELSAT global system of communications satellites in operation today is a development covering four generations of satellites. Starting with the INTELSAT I or “Early Bird” satellite launched in 1965, each succeeding satellite series has provided more capability by the introduction of new coverage areas or increased telephony and television capacity Today with the INTELSAT III and IV satellites in operation, service is being provided between earth stations around the world of a quality that meets all appropriate CCIR and CCITT requirements. In this paper, the global network is examined with a view to determining those technical factors that impact on the design options of communications satellites of the future. The factors and trends expected to influence future satellite designs and configurations are discussed. Specifically these are derived from analyses of the volume and the distribution in each ocean area of the system traffic, from analysis of the available modulation and multiple access techniques, from estimates of possible traffic growth rates for the time frames of interest, as well as from considerations of the availability of launch vehicles, of the present and future state of technology, of reliability and continuity of service requirements and of impact on earth station design and modifications.