Performance analysis of load-adaptive/TDMA systems with applications to integrated-services satellite networks

Abstract

A load-adaptive/TDMA multiple-access communications link which serves to interconnect broadband multi-media packet streams is considered. In particular, the use of a satellite backbone communications link whose channels are dynamically assigned to the network stations is investigated. Each station supports packetized voice and data message streams. Incoming streams to a station are statistically multiplexed by the station across the backbone channels currently allocated to this station. To enhance the multiplexing process, a variable bit-rate packet-voice encoding scheme is also employed. Stations issue periodically requests for backbone channel allocations, based upon their loading status. We introduce two distinct algorithms for allocating the shared backbone channels to the stations. We develop analytical methods for the analysis and design of such integrated multiplexing/multiple-access networks. Performance measures include voice and data packet delays and packet blocking probabilities. Voice stream performance is also characterized by the average number of bits per sample used by the voice encoding scheme. The fairness issues between the two allocation algorithms are described and discussed. The effects of the propagation delay across the backbone link are especially demonstrated.<>