Adaptive backoff mechanism for OFDMA random access with finite service period in IEEE802.11ax

摘要

In next generation wireless LAN standard which is called IEEE802.11ax, Orthogonal Frequency Division Multiple Access (OFDMA) random access has been adopted as an uplink multi-user transmission technology. In this paper, we propose an adaptive backoff algorithm for OFDMA random access. Due to the finite service period defined by the standard, random access OFDMA sessions are discontinuous in time which may result in performance degradation when naive implementations are performed. Via computer simulations, we show that near maximum throughput is consistently achieved even in the case of dense environment. In addition, we explain a method for accurately estimating the number of OFDMA random access users, a key parameter in the proposed adaptive method.