Beyond Wi-Fi 7: Spatial reuse through multi-AP coordination

Wi-Fi 7, based on the IEEE 802.11be amendment, is designed to increase the maximum achievable throughput, expand the range of operating frequencies, and improve latency and jitter in worst -case scenario. In the context of the discussions to shape what Wi-Fi 8 will be, the IEEE 802.11 WG is evaluating multi -AP coordination as a strategy to further improve network performance in several aspects. MAC -driven multi -AP coordination strategies include coordinated Orthogonal Frequency Division Multiple Access (c-OFDMA), coordinated Time Division Multiple Access (c-TDMA), and coordinated Spatial Reuse (c -SR). In c-OFDMA, a set of APs transmit during a Transmission Opportunity on different channels, whereas in c-TDMA, the APs take turns transmitting on the same channel during a Transmission Opportunity. Instead, in c -SR, a set of APs transmit simultaneously on the same channel and during the same Transmission Opportunity. In this paper, we focus on c -SR. We introduce a c -SR interference model and present a strategy based on the proposed model for estimating groups of APs that can transmit successfully simultaneously. We implemented the proposed approach in the multi -AP coordination framework of ns-3 that we developed to analyze c-TDMA. We then thoroughly evaluate the performance of the proposed c -SR scheme via ns-3 simulations. The proposed scheme allows increasing the system throughput of a dense deployment up to 2.3 times as well as substantially reducing the Head of Line delay.