Distributed Wi-Fi Interference Coordination for Dense Deployments

Unlicensed spectrum is increasingly being used by mobile operators to meet the mobile traffic demand, and Wi-Fi is foreseen as one of the technologies for implementing mobile traffic offloading. However, Wi-Fi efficiency does not scale well as node density increases, and IEEE 802.11ax Task Group (TGax) was created in 2014 for developing Wi-Fi technology enhancements in dense deployments. This paper investigates Wi-Fi performance in the presence of Overlapping Basic Subscriber Set (OBSS) Wi-Fi networks in indoor dense deployments. We observe that Wi-Fi could benefit from scheduled operation with proper OBSS interference coordination. We propose a novel distributed interference coordination scheme for Wi-Fi scheduled mode operation, and evaluate it through system-level simulations. Results indicate that the proposed scheme provides significant improvements over Enhanced Distributed Channel Access (EDCA) for downlink (DL) traffic.