6th International ICST Conference on Communications and Networking in China

Research Article

An Efficient Power Allocation Algorithm with Fairness Constraints in Cognitive OFDMA System

  • @INPROCEEDINGS{10.1109/ChinaCom.2011.6158275,
        author={Lu Ye and Zhaoyang Zhang and Zhipeng Zhang and Benkang Gong and Lianxiang Wang},
        title={An Efficient Power Allocation Algorithm with Fairness Constraints in Cognitive OFDMA System},
        proceedings={6th International ICST Conference on Communications and Networking in China},
        publisher={IEEE},
        proceedings_a={CHINACOM},
        year={2012},
        month={3},
        keywords={cognitive ofdma power allocation fairness constraints water-filling},
        doi={10.1109/ChinaCom.2011.6158275}
    }
    
  • Lu Ye
    Zhaoyang Zhang
    Zhipeng Zhang
    Benkang Gong
    Lianxiang Wang
    Year: 2012
    An Efficient Power Allocation Algorithm with Fairness Constraints in Cognitive OFDMA System
    CHINACOM
    IEEE
    DOI: 10.1109/ChinaCom.2011.6158275
Lu Ye1,*, Zhaoyang Zhang1, Zhipeng Zhang1, Benkang Gong1, Lianxiang Wang1
  • 1: Zhejiang University
*Contact email: 05hhbyl01@zju.edu.cn

Abstract

An efficient power allocation algorithm for OFDMA-based cognitive radio (CR) systems with the total power limitation, interference constraint, and proportional fairness requirement is proposed. While solving the optimization problem with multiple constraints is computationally infeasible, we exploit the structure of the nonlinear equations to obtain an approximate solution. It can fairly allocate power among the second users (SUs) with significantly reduced complexity. Furthermore, we replace the traditional water-filling (WF) algorithm with a much faster alternative that can avoid repeated iterations to facilitate subcarrier power allocation within a single SU. Simulation results show the proposed algorithm can maintain a higher capacity, while effectively ensure the fairness among SUs compared with the referenced algorithms.