Energy Efficient SBS Selection and Resource Allocation for MC-NOMA based HetNets

Heterogeneous networks (HetNets) based on multicarrier non-orthogonal multiple access (MC-NOMA) by allowing several users to share the same spectrum can effectively enhance the system’s spectral efficiency (SE). However, invoking NOMA in HetNets causes the complexity of interference control. In addition, improving energy efficiency (EE) is a critical factor in 5G communication networks. Therefore, in this work, we investigate a joint small base station (SBS) selection, power and sub-channel (SC) allocation problem to maximize system’s EE and manage network’s interference under the constraints of minimum quality of service (QoS) requirement for a downlink MC-NOMA based HetNets. Since the formulated problem is non-convex, we split it into 2 sub-problems. First, we propose an advanced matching-based algorithm for joint SBS selection and SC allocation subproblem. The Dinkelbach and successive convex approximation methods are subsequently employed to address the power allocation sub-problem. The simulation results demonstrate the effectiveness of the considered algorithms.