认知无线电网络中基于噪声功率估计的能量检测性能  

Performance of Energy Detection Based on Estimated Noise Power in Cognitive Radio Networks

作　　者：刘义贤[1] 季飞[1] 余华[1] 

机构地区：[1]华南理工大学电子与信息学院,广州510640

出　　处：《电子与信息学报》2011年第6期1487-1491,共5页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(61071212;U1035003);华南理工大学中央高校基本科研业务费(2009ZM0248)资助课题

摘　　要：该文分析了利用噪声功率估计值进行能量检测时判决门限的计算问题,推导出检测性能的Q函数表达式。为达到期望的检测性能,判决门限不能直接由噪声功率估计值替换已知的噪声功率得到,必须进行修正。文中给出了修正判决门限的闭合表达式,极大地简化了检测性能分析和判决门限计算。仿真结果表明,在估计样点数为20时,对比原判决门限,基于修正判决门限的误警概率减少了15%,有效地提高了认知无线电网络的吞吐量。This paper analyzes the issue of calculating the threshold for energy detection when an estimated noise power is used. The corresponding closed-form detection performances of energy detection are derived in the terms of Q function. To achieve the expected detection performance, the threshold cannot be derived by replacing the exact noise power with the estimated ones and must be modified. Moreover, the closed-form expressions of modified thresholds are given in this paper, which simplify the analysis of the detection performances and the calculation of the threshold. Simulation results show that when the sample number is 20, compared to the original threshold, the false alarm probability based on the modified threshold decreases 15%. The throughput of Cognitive Radio （CR） networks can be effectively increased.

关 键 词：认知无线电 频谱感知 能量检测 噪声功率估计 

分 类 号：TN92[电子电信—通信与信息系统]