Energy-efficient resource allocation based on proportional fairness in OFDM multi-user systems

This paper considers the problem of resource assignment with proportional fairness for multi-user OFDM relaying systems in single cell. An energy-efficient strategy is proposed including relay selection, subcarrier assignment and power allocation subjecting to individual power constraint. The optimal purpose is to maximize the sum of the logarithm per user rate per power. The optimization problem is decomposed into some sub-problems, since the joint optimization problem leads to a mixed-fraction time-complete problem. First, Dinkelbach's method is employed for transforming the fractional programming to integral expression. Then, continuous relaxation is used to solve the dual problem by bisection method and Lagrangian dual decomposition method. Simulation results show that the proposed algorithm has a good trade-off between the throughput and fairness compared with other schemes. Copyright © 2015 Binary Information Press.