Dynamic sensitivity control of access points for IEEE 802.11ax

Abstract

The popularity and wider acceptance of IEEE 802.11 based WLANs has resulted in their dense deployments\ud in diverse environments. While this massive deployment can potentially increase capacity and coverage, the current\ud physical carrier sensing of IEEE 802.11 cannot limit the overall interference induced and also cannot insure high\ud concurrency among transmissions. Recently, the IEEE 802.11 working group has continued efforts on developing\ud WLAN technology through the creation of the TGax, which aims to improve efficiency of densely deployed IEEE 802.11\ud networks. In this paper, we propose a Dynamic Sensitivity Control for Access Point (DSC-AP) algorithm for IEEE\ud 802.11ax. This algorithm dynamically adjusts the Carrier Sensing Threshold (CST) of an AP based on received signal\ud strength from its associated stations and interfering APs. We show that the aggregate throughput of a dense network\ud (under asymmetric traffic conditions) utilizing DSC (both at the stations and AP) is considerably improved (i.e. up to\ud 32%) when compared with legacy IEEE 802.11. © 2016 IEEE.Peer ReviewedPostprint (published version

Stochastic Geometry Analysis of Individual Carrier Sense Threshold Adaptation in IEEE 802.11ax WLANs

“…We compare the numerical results with those of a Monte Carlo simulation. This section uses the CST function proposed in [2] as θ(•). In Section IV, the trend of the optimal CST function for the received power is obtained based on the stochastic geometry.…”

“…In detail, the CST function is set as shown in Fig. 2 seen in dynamic sensitivity control [2] with the CST limited between Θ and Θ +a, where a denotes the maximum increment in the CST. The CST as a function of the communication distance θ (1) (r) is expressed as follows:…”

“…where c denotes a parameter. Assuming that the CST is set according to dynamic sensitivity control [2], the CST is expressed as follows:…”

“…Each AP is assumed to adjust its CST according to its path loss y k − x k −α = r −α k estimated from the average received power, where r k represents the communication distance between AP k and associated STA and P represents the initial transmission power of all APs. Note that adjusting the CST according to each average received signal power has been a strategy in previous studies [1], [2] as an approach to throughput improvement. 1 Relation (4) implies that the CST adjustment according to the average received power is equivalent to that according to the communication distance.…”

“…collisions owing to harmful interference and, hence, optimizing the CST value is challenging. As a setting of the CST, dynamic sensitivity control, in which APs or stations (STAs) adjust their CST based on the average received power from their associated AP or STA, has been suggested [1], [2]. In dynamic sensitivity control, the CST is set to increase with the received power from the communicating AP or STA.…”