Performance evaluation of IEEE 802.11ah and its restricted access window mechanism

In this paper we provide an analytical model to compute the throughput and energy consumption of IEEE 802.11ah, the new Sub-1 GHz WiFi standard. The analytical model assumes known collision and error probabilities and applies to both basic and RTS/CTS access mechanisms. Comparison with simulation results shows that the model is extremely accurate in predicting the system throughput and energy consumption. We also investigate the IEEE 802.11ah system including the new restricted access window (RAW) mechanism, and compare it to the basic scheme. The obtained results show that the RAW mechanism can provide substantial improvements in the system performance, in terms of throughput, packet delay and energy consumption, in particular in highly-loaded dense network scenarios. These findings affirm and substantiate the prospects of IEEE 802.11ah as one of the key enabling technologies for wide-scale low-cost and energy-efficient M2M deployments and IoT applications in the future.