Energy-Efficient Resource Allocation Under Imperfect Channel Estimation for NOMA-Assisted Heterogeneous Networks With Wireless Backhaul

Given the exponential surge in wireless devices and data traffic, a key objective for forthcoming wireless communication systems lies in reducing energy consumption, thereby adhering to the emerging trend of green communication. Thus, devising an energy-efficient resource allocation scheme for Heterogeneous Networks (HetNets) is of utmost importance. In this paper, on the purpose of reducing energy consumption while ensuring users’ Quality of Service (QoS) requirements, we construct an energy-efficient optimization function for joint allocation of sub-channels, power and wireless backhaul bandwidth (JASPW) in NOMA-assisted HetNets with wireless backhaul considering imperfect channel state information (CSI), which poses non-convex and hybrid nonlinear challenge, providing an un-affordable computational complexity. Unlike the previous approach of decomposing the JASPW issue into several sub-convex problems, to tackle the problem efficiently, we first give the closed-form expressions through the derivation of the outage probability constraints, thus transforming the problem into a deterministic and convex one, subsequently, we propose a novel quantum-inspired equilibrium optimizer (QEO) algorithm to allocate the joint resource simultaneously, thereby obtaining the optimal resource allocation solution. Simulation results indicate that the proposed QEO yields an outstanding performance over other strategies in different communication scenarios.