Intersatellite links for international communications

An overview is given of the Intelsat efforts to develop the necessary hardware and to evolve system plans based on the use of intersatellite links (ISLs). The presentation is broadly divided into the two main areas of technology development and system applications. It is noted that work has been started on computer simulation of ISLs, fabrication of an ISL test bed, and preliminary surveys of such links at optical frequencies. Concepts under consideration include the dual primary concept, the extended region concept, interregional ISLs, and satellite clusters. The advantages and disadvantages to a modular approach to space segment growth are enumerated. The optimal approach is thought to be one which provides interconnectivity for all regional networks to the international nodes in the ocean regions.