Adaptive Traffic Load in IRSA-NOMA Prioritizing Emergency Devices for 6G Enabled Massive IoT

Irregular repetition slotted ALOHA (IRSA) based non-orthogonal multiple access (NOMA) with priority adaptive traffic load (ATL) (PATL-IRSA-NOMA) is proposed to prioritize the performance of emergency devices in 6G enabled massive Internet of Things. In PATL-IRSA-NOMA, emergency devices (ED) and regular devices (RD) are coexisting and differentiated by access probability before sending packets, where RD performing traffic load estimation and applying ATL to access the channel. Different from conventional ATL that is performed by all users/devices, priority ATL in PATL-IRSA-NOMA is only performed by RD and reduces the contention of RD in IRSA-NOMA channel. The superior of PATL-IRSA-NOMA over conventional IRSA-NOMA is shown in terms of packet loss rate and throughput for both ED and RD groups.