Conflict-aware multicast in multiuser diversity-based wireless networks

Abstract

Owing to the broadcast nature of the wireless medium, information transmitted to one or many users is often blocked by other concurrent transmissions. In a random access network, this issue, known as access conflicts, has a great impact on the overall performance, especially when performing multicast communications. To make the multi-rate multicast more vigorous and to reduce its vulnerability to access conflicts, we introduce an efficient, conflict-aware multicast transmitter scheduling that largely reduces the effect of close-by transmissions. We exploit the diversity between users to provide an efficient multicast strategy that enables each transmitter to select the data rates to use to serve the interested neighbours. Subsequently, we introduce two new concepts: the Transmission Rate-based Interference graph (TRIGraph) and the Concurrent Multi-rate Multicast Transmitter Set (CMMS). By means of a mathematical formulation, we prove that the transmitter schedule proposed outperforms the conflict-unaware multi-rate multicast schemes suggested.