Towards a Realistic Primary Users' Behavior in Single Transceiver Cognitive Networks

This letter presents new results obtained with a novel MAC scheme designed to be reliable and maximize the throughput of a single-hop network. Contrarily to the IEEE 802.11 MAC scheme, all nodes adopt a common optimal contention window size for unicast and broadcast transmissions, which is based on a common view of the channel. In this way, the conditional collision probability is independent of the type of traffic (broadcast or unicast). Simulation results for different amounts of broadcast/unicast traffic indicate that our approach significantly outperforms IEEE 802.11, exhibiting broadcast aggregate throughput gains up to 40%. Moreover, the simulation results indicate that the probability of successful transmitting a broadcast frame can be also improved up to 50% and, as the number of nodes increase, broadcast frames can obtain approximately the same reliability and throughput achieved by IEEE 802.11 unicast frames.