Improving the capacity of future IEEE 802.11 high efficiency WLANs

In future´s high density Wireless Local Area Networks (WLANs), to improve the overall throughput, we envision the optimization of the MAC protocols and mechanisms. Traditionally, it´s clear in the literature that Transmit Power Control (TPC) is chosen as one of the most powerful tools for optimizing MAC protocols. However, the TPC is not always possible to implement due to hardware and licensing limitations on one hand, and on the other, its unbalanced use results in starvation situations. In the same context, the Clear Channel Assessment (CCA) threshold adaptation is proving its effectiveness. This adaptation is preferable to TPC that behaves aggressively towards transmitters having lower transmit power. In this paper we show that CCA adaptation mechanism may be used effectively to optimize the spatial reuse in dense WLAN deployments. For a dense IEEE 802.11n network topology, our simulations show a global gain of 190% in aggregate throughput compared to the current bound assumed by the present MAC protocol.