Energy-efficient resource allocation for OFDMA relay systems with imperfect CSIT

• Published in: Science China. Information sciences 2015-08, Vol.58 (8), p.126-138
• Main Authors: Wang, XiaoMing, Zheng, FuChun, Zhu, PengCheng, Meng, Chao, You, XiaoHu
• Format: Article
• Language: English
• Subjects: Computer Science; Convexity; Frequency division multiple access; Information Systems and Communication Service; Iterative algorithms; OFDMA; Optimization; Orthogonal Frequency Division Multiplexing; Relay systems; Research Paper; Resource allocation; Statistical analysis; 中断概率; 中继系统; 信道状态信息; 凸优化问题; 正交频分多址; 能量有效; 资源分配
• ISSN: 1674-733X; 1869-1919
• DOI: 10.1007/s11432-015-5340-8

In this paper, we propose an energy-efficient resource allocation scheme for the downlink of decode- and-forward relay-assisted orthogonal frequency division multiple access systems. The resource allocation is designed based on imperfect channel state information at the transmitter. We jointly optimize the power allocation, data rate allocation, and subcarrier allocation to maximize the system energy efficiency （EE）. We formulate the EE problem as a probabilistic mixed non-convex optimization problem, in which the individual power constraints and the outage probability requirements are considered. An iterative algorithm based on bisection method is given to transform the optimization problem into a standard concave form. Also, we consider a proportional fairness design for the EE maximization problem. Simulation results illustrate the effectiveness of the proposed algorithm.