Adjusting OBSS/PD Based on Fuzzy Logic to Improve Throughput of IEEE 802.11ax Network

Abstract

AbstractThe densely-deployed Wireless Local Area Network (WLAN) exhibit underutilization of radio frequency, low network performance, etc. To enhance frequency spectrum efficiency and improve network performance, the IEEE 802.11ax standard, published in this year, introduces some new technologies, including Orthogonal Frequency Division Multiple Access (OFDMA) and Spatial Reuse (SR). In the SR, Overlapping Basic Service Set (OBSS) Packet Detection (OBSS/PD) is applied to increase parallel transmissions. The standard, however, leaves the unsolved problem of how to set suitable OBSS/PD for the nodes in OBSS. This paper makes efforts to solve this problem and proposes the fuzzy logic based OBSS/PD adjustment (FLOPA) scheme. The proposed FLOPA scheme integrates SR with OFDMA and lets Access Point (AP) maintain the OBSS/PDs for multiple nodes. The FLOPA embeds the fuzzy control system, in which the received signal strength indicator (RSSI), network throughput, and currently-applied OBSS/PD are chosen as input variables and the output variable is used to adjust the OBSS/PD. Simulation results show that the proposed scheme can effectively improve network throughput. Compared with the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) scheme in 802.11ax standard, the network throughput can be increased by more than 100%.KeywordsIEEE 802.11ax standardSpatial reuseCarrier sense thresholdFuzzy controlOrthogonal Frequency Division Multiple Access