Exploiting Multi-User Diversity for Uplink Throughput in IEEE 802.11 WLANs

In multi-rate 802.11 networks, stations with better uplink conditions should access the shared channel more frequently than the ones with worse uplink conditions to enhance the aggregated throughput, which is referred to as multi-user diversity. In this letter, we propose Adaptive Basic Rate Set (ABRS) that uses the time gap between DIFS and EIFS for a prioritized channel access while minimizing starvation. ABRS requires the change in the firmware only at access points with no modification to the standard. Simulation results reveal that ABRS effectively prioritizes stations with higher bit rates; the aggregate uplink throughput is improved up to about 30-70% even in mobility scenarios.