Improving throughput of wireless LANs with transmit power control and slotted channel access

Throughput of wireless LANs is interference-limited. Newly deployed access points (APs) can hardly bring throughput gain without careful design. Although transmit power control (TPC) can improve spatial reuse of the channels, the achievable throughput also heavily depends on other factors, such as rate adaptation, which are seldom touched in previous works. In addition, TPC protocols, designed with the assumption that all nodes have the same capability, do not work well when legacy nodes not supporting TPC coexist. In this paper, (i) we exploit joint rate adaptation and TPC to improve system performance and suggest choosing power to maximize throughput after taking tradeoff between transmit rate and spatial reuse of channels, and, (ii) we suggest using the NAV (network allocation vector) mechanism to create virtual slots in the scenario where legacy nodes coexist with new nodes running TPC. Simulation results show that (i) the proposed TPC scheme can effectively improve both total throughput and fairness, and, (ii) the slotted channel access scheme ensures that throughput gain can be achieved by nodes running TPC while the performance of legacy nodes not supporting TPC is not degraded.