Resource-Efficient NOMA Transmission via Joint Bandwidth and Rate Allocations

In this letter, we investigate the joint channel bandwidth and rate allocations for downlink non-orthogonal multiple access with the objective of maximizing the resource utilization efficiency (RUE). In particular, we take into account the utility of base station (BS) in serving the mobile terminals' traffic and the cost in consuming channel bandwidth and measure the RUE as the ratio between the BS's utility and the total power consumption. Despite the non-convexity of the joint optimization problem, we propose a three-layered vertical decomposition and design an efficient algorithm to compute the optimal solution. Extensive numerical results are provided to validate the performance of our proposed algorithms.