Spectrum Efficiency Optimization in V2X Communications: A NOMA-Based Solution

The increasing prevalence of intelligent transportation systems necessitates more frequent communication between vehicles and the external environment. In this context, with a large number of user connections and frequent information exchange, efficient utilization of limited spectrum resources is essential. Moreover, the rapidly dynamic network environment poses significant challenges to resource allocation in Vehicle-to-Everything (V2X) communication. To address these issues, we propose a solution based on Non-Orthogonal Multiple Access (NOMA) technology, featuring centralized spectrum allocation and distributed power control. Firstly, by applying NOMA within vehicle groups, we can further reduce communication delays and enhance the system capacity of V2X systems. Additionally, the distributed power control algorithm predicts the future dynamic Channel State Information (CSI) trends of terminal vehicles, controlling and adjusting the transmission power for NOMA communication in each cycle to ensure the reliability of link transmission. Simulation results demonstrate that our proposed algorithm outperforms traditional existing schemes.