Optimal Power Allocation in Cache-Aided Non-Orthogonal Multiple Access Systems

This work combines non-orthogonal multiple access (NOMA) and caching, two prominent techniques for future communication networks. Specifically, a cache-aided cellular network with Rayleigh fading channels is analyzed. By exploiting the channel distribution, users requests, and cache contents in given time, an optimal power allocation policy for the superposed signal is derived. The goal is to maximize the system success probability, i.e., the probability that all users can successfully decode their desired signals. The analysis highlights the benefits of introducing caching to NOMA-based systems. Simulation results confirm the analysis and demonstrate the efficiency of the proposed power allocation.