Satellite communication systems for multimedia services

This paper proposes a satellite communication system configuration suitable for multimedia communication and discusses the requirements for the network system. In the proposed system, multi-speed digital data is multiplexed and distributed to users by satellites. The distribution data is received not only at users´ homes directly but also at the head-ends of CATV systems. Users can get desired information from multiplexed data by using a multimedia adapter consisting of a receiver and a decoder. Each user can send requirements to the information providers (IPs) via individual low bit-rate lines and the IPs can manage and maintain the user orders through those lines. The satellite network will exist not as a stand-alone system but as a virtual network in B-ISDN, which will be combined with terrestrial optical fiber links, radio links, and satellite links. As the first step in achieving a multimedia service network, a high bit-rate satellite system and a medium bit-rate satellite system are developed. In the former system, a high bit-rate transmission capability of 156 Mbps is attained. In the latter system, a very small transportable earth station of 1.2-mφ antenna is actualized. To clarify the effectiveness of using satellite communication systems for multimedia services, a demonstration using transportable earth stations of the medium bit-rate satellite system is now being carried out