Generalized NOMA-ARQ With Round-Robin IIC for IoT Systems

This article investigates the performance of non-orthogonal multiple access (NOMA) integrated with automatic repeat request (ARQ) for point-to-point Internet of Things (IoT) wireless backhaul links. The proposed framework is generalized accommodate an arbitrary number of users, incorporates round–robin (RR) scheduling, and use iterative interference cancellation (IIC) with chase combining (CC) to enhance fair power allocation while reducing the packet drop rate (PDR). The results reveal that NOMA-ARQ with IIC significantly outperforms conventional orthogonal multiple access (OMA) in various scenarios. The signal-to-noise (SNR) gain in PDR performance is particularly evident in moderate to high SNR conditions, ranging from 13 to 35 dB, and for scenarios involving three users with multiple transmission attempts. The proposed approach demonstrates up to a threefold increase in system throughput compared to OMA, highlighting its potential for enhancing backhaul performance in dense IoT deployments. These findings highlight the potential of IIC-assisted ARQ-NOMA to address the requirements for spectrum efficiency and data reliability effectively.