IEEE 802.11ax standard aims to improve performance in scenarios with densely deployed access points (APs) and stations (STAs). It provides an uplink OFDMA-based random access (UORA) mechanism which allows the STAs that failed to report their butter status to the AP to transmit data, or the unassociated STAs to transmit an association request frame. Existing studies on UORA performance analysis focus on the analytical model of contention of resource units (RUs) within single basic service set (BSS), which is only in frequency domain. However, in high-density scenarios, where multiple BSSs may locate within the interference range of each other and work on the same channel, the performance of UORA not only relates with the contention in frequency domain, but also associates with the contention in time domain among multiple APs or legacy STAs working on the same channel. As the UORA mechanism is based on the successful transmission of trigger frame (TF), the transmission of TF and UORA process should be analyzed as a whole system. In this paper, we combine the transmission of TF and UORA process, and build a systematic theoretical model to practically characterize the performance of UORA in multi-BSS scenario. The average throughput and successful probability of UORA are derived. In addition, we validate our analysis through extensive simulations.
Random Access Modelling and Performance Analysis for the 802.11ax UORA Mechansim in Multiple BSSs
2022-09-01
3934096 byte
Conference paper
Electronic Resource
English