Low complexity energy-efficient resource allocation in down-link dense femtocell networks

Femtocells have attracted growing attentions in academia, industry, and standardization forums in recent years. However, most of existing works on femtocell networks are focused on spectrum efficiency and interference mitigation, energy efficiency aspect is neglected. In this paper, we investigate the maximization of energy efficiency of downlink OFDMA dense femtocell networks by efficient resource allocation. To decrease the complexity, joint subchannel allocation and power control are decomposed into two steps. Power control has been modeled as a non-cooperative game, a closed-form best response of transmit power is obtained. Considering fairness and low complexity, a fair time-averaged subchannel allocation metric have been derived out. Based on that, we propose a distributed suboptimal subchannel allocation and optimal power control algorithm. Simulation results show that the proposed algorithm has a low complexity with slight loss of energy efficiency compared with Round-Robin Scheduling and a noncooperative energy-efficient power optimization algorithm.