User-centric energy efficiency fairness in backscatter-assisted wireless powered communication network

In order to address the unfair user-centric energy efficiency (EE) problem caused by channel difference in the backscat-ter-assisted wireless powered communication network, a resource allocation scheme was proposed. Firstly, a mixed integer nonconvex fractional programming problem was formulated to maximize the minimum user-centric EE, subject to the quality of service and energy-causality constraints. Based on the generalized fractional programming theory, the original problem was transformed into a mixed integer nonconvex subtraction problem. With the aid of the slack variable, the proof by contradiction, the auxiliary variable and the mixed integer nonconvex subtraction problem were further transformed into an equivalent convex problem. Finally, an iterative algorithm was proposed to obtain the optimal solutions. Computer simulations validated the quick convergence of the proposed iterative algorithm, and that the developed resource allocation scheme efficiently guarantees the fairness among users in terms of EE. © 2020, Editorial Board of Journal on Communications. All right reserved.