Low-Complexity Energy-Efficient Resource Allocation for Uplink OFDMA Systems

Energy efficiency is becoming more and more important for mobile devices in future green radio network. This paper addresses the tradeoff between energy-efficiency (EE) and spectral efficiency (SE) in uplink multiuser orthogonal frequency division multiple access (OFDMA) systems. In this paper, EE is measured by the sum of instantaneous bits-per-Joule of each user, and it is optimized with the restrictions on both the minimum rate requirements and available transmit power over frequencyselective channels. Based on this optimization model, a novel low-complexity energy-efficient resource allocation algorithm is proposed. Simulation results demonstrate that the proposed scheme provides a better tradeoff between SE and EE than the conventional schemes with reduced complexity.