Sum Rate Maximization for NOMA With Simultaneous Cache-Enabled D2D Communications

Mobile applications that operate on end user devices such as on-demand video streaming, social media content are becoming increasingly data-centric. They require high data rate and are frequently requested by multiple users. Non-orthogonal multiple access (NOMA) and wireless caching are potential candidates that could keep pace with these demands. In this letter, we propose a novel cellular NOMA model whereby users in spatial proximity would be able to exchange their useful cached-data files simultaneously in full duplex mode via underlaid device-to-device (D2D) communications. We implement convex optimization to maximize the sum rate of the system which is a key performance metric for cellular networks. Simulation results demonstrate the superior performance gains from our proposed model over existing approaches.