ATM-based multimedia communication via satellite

Within the next years, a large number of new satellite systems for broadban d multimedia communications will be developed, mainly for fixed terminals, but to a lesser degree also for portable and mobile terminals. The most imp ortant systems will be based on low earth orbit (LEO) satellite constellati ons with intersatellite links (ISLs), and will be seamlessly integrated int o the environment of terrestrial broadband networks. Since most of the terr estrial broadband networks will be based on the Asynchronous Transfer Mode ATM, it is advantageous for the satellite networks to adopt the ATM transmi ssion scheme and implement ATM switches on board the satellites. However, c ompared to communication in fixed networks, satellite communication is char acterised by special constraints (limited bandwidth, propagation delay, tra nsmission errors, dynamic network topology) requiring the development of a new ATM-based communication technology. In the paper, an ISL-based LEO sate llite network for multimedia communication will be considered. Several rele vant aspects will be discussed, such as the system architecture, the system requirements, and the protocol architecture. Since the users access the sa tellite network via a radio interface, an error control scheme and a multip le access scheme suitable for multimedia communication must be implemented. The aspects of TDMA- and CDMA-based medium access control are discussed. F urther issues are ATM resource management, radio resource management, and I SL routing. Finally, methods for terminal antenna steering are adressed, an d the demonstration of aeronautical multimedia communication via the ITALSA T satellite is described.