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

Abstract

Heterogeneous networks (HetNets) based on multi-carrier 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 an important issue in 5G communication networks. Therefore, in this paper, we investigate a joint small base station (SBS) selection, sub-channel (SC) and power 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. Due to the non-convexity of the formulated problem, we divide the problem into two sub-problems. First, we propose an advanced matching-based algorithm for joint SBS selection and SC allocation sub-problem. Then, we use Dinkelbach and successive convex approximation methods for the power allocation sub-problem. The results of the simulation show the effectiveness of the proposed algorithms.