A Novel MAC Protocol of Uplink OFDMA-IDMA Random Access

The 802.11ax standard introduced Uplink Orthog-onal Frequency Division Multiple Access (UL-OFDMA) with Random Access (UORA) to enhance the capabilities of Stations (STAs), including those that have recently woken up from sleep or are involved in applications without predefined requirements. UORA allows for system efficiency adjustments by varying the number of Resource Units (RUs) in OFDMA. However, its maximum efficiency is limited to 37 %, and performance declines as the number of STAs increases. This paper presents a novel MAC protocol to improve system efficiency by integrating Interleave Division Multiple Access (IDMA) into UORA. We provide a mathematical model to analyze the efficiency and latency of this enhanced protocol. The results demonstrate that both efficiency and latency are more than twice as good as UORA.