ETP algorithm: Increasing spatial reuse in wireless LANs dense environment using ETX

To address the issues related to the extreme densification of wireless networks, namely increased interference and lower overall throughput, the IEEE 802.11ax project was formed to revise the standard specifications for IEEE 802.11ac in order to increase the spectrum efficiency and most notably the per-user throughput by a factor of four. Improving Spatial Reuse (SR) is seen as one of the main techniques for achieving this goal. In this paper, we explore the so-called Overlap Basic Service Set Physical Detection (OBSS_PD)-based SR technique introduced in IEEE 802.11ax, which aims to increase SR by adapting both stations' Carrier Sensitivity Threshold (CST) and transmission power. To that end, OBSS_PD PD-based SR defines a proportional relationship between CST and the transmission power. In this article, we propose a novel and dynamic algorithm to implement an OBSS_PD PD-based SR. This so-called ETX To Power (ETP) algorithm uses the Expected Transmission Count (ETX) metric to dynamically compute the transmission power and the CST to use. Simulations are used to evaluate ETP in a dense scenario. We show that the overall system throughput is improved by 40 % compared to IEEE 802.11 legacy networks and at the same time the 5th percentile throughput is also increased by 22 %.