Hybrid Relaying Cooperative NOMA with Adaptive and Opportunistic Resource Allocation for Downlink Optimization in B5G Networks

This research investigates the optimization of downlink performance metrics, including spectral efficiency, data rates, and coverage, for cell-edge user equipment (UE) in Beyond 5G (B5G) networks using a hybrid relaying Cooperative Non-Orthogonal Multiple Access (CNOMA) framework.The system architecture consists of a gNodeB (gNB) located at the cell center, serving both an intra-cell cluster (ICC) near the gNB and a cell-edge cluster (CEC) positioned farther away.To address the challenges faced by UEs in these clusters, particularly random signal strength deprivation due to deep Rayleigh fading, two novel resource allocation strategies are proposed: Channel-Aware Adaptive Fair (CAAF) Power Allocation and Resource-Free Best Positioned Opportunistic Relay Selection (RFBP-ORS).The CAAF method ensures fair and dynamic power allocation by leveraging real-time channel state information (CSI), while RFBP-ORS selects the optimal relay based on resource availability and spatial positioning, thereby maintaining uninterrupted connectivity.Simulation results reveal that the proposed methodologies significantly enhance the achievable data rates by up to 140% compared to conventional CNOMA, reaching 5.8 bps/Hz at 12.5 dB SINR.They also improve energy efficiency to 1 Gb/J and achieve a 10 times reduction in outage probability for cell-edge users at 12.5 dB SINR, thereby demonstrating strong suitability for B5G deployment requirements.The proposed CNOMA-based hybrid relaying scheme outperforms conventional resource allocation approaches, offering a reliable and efficient communication framework for B5G networks, particularly benefiting UEs near the cell edge.These findings underline the potential of CNOMA-based adaptive and opportunistic resource allocation in addressing the evolving demands of next-generation wireless networks.