Data Rate-Based Grouping to Resolve Performance Anomaly of Multi-Rate IEEE 802.11ah IoT Networks

In this letter, we consider IEEE 802.11ah based IoT network with rate adaptation, where all the devices contend for the channel access using group-based restricted access window (RAW) mechanism with default uniform grouping scheme. In such multi-rate networks, as each group contains distinct data rate devices, we have observed drastic degradation of throughput performance due to performance anomaly. To resolve this problem, we propose a novel grouping scheme based on data rates. Analytical and simulation results show that the proposed scheme significantly improves aggregate throughput of RAW mechanism with minimal additional overhead, when compared to default uniform grouping scheme.