The Time Fairness Strategy of Minimum Contention Window for IEEE 802.11 WLAN

DCF application has serious inequities in multi-rate wireless LAN: the time occupation of the high rate site being in channel is much smaller than the time of low-rate site. It can only receive the same throughput with the low-rate site. This paper will use the idea of differentiated services, and bring out MDCF with fair access time. By setting different initial contention windows according to sites with different rates, MDCF can guarantee the proportional probability between access and transmission rate, therefore ensure the fairness of access time. Theoretical analysis and simulation results show that MDCF can greatly improve the fairness of time and throughput in multi-rate wireless LAN.