Underlay认知网络中时频重叠OFDM信号的信噪比盲估计  

Blind SNR Estimation of Time-Frequency Overlapped OFDM Signals for Underlay Cognitive Radio Networks

作　　者：刘明骞[1,2,3] 郭菲 李兵兵 陈钱[2] 吴芸[3] LIU Ming-qian;GUO Fei;LI Bing-bing;CHEN Qian;WU Yun(State Key Laboratory of Integrated Service Networks,Xidian University,Xi＇an,Shaanxi 710071,China;School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing,Jiangsu 210094,China;Xuzhou LEO Medical Equipments Co.,Ltd.,Xuzhou,Jiangsu 221116,China)

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071 [2]南京理工大学电子工程与光电技术学院,江苏南京210094 [3]徐州雷奥医疗设备有限公司,江苏徐州221116

出　　处：《电子学报》2018年第6期1510-1514,共5页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61501348;No.61271299);陕西省自然科学基础研究计划(No.2016JQ6039);中国博士后科学基金(No.2017M611912);江苏省博士后科研资助计划(No.1701059B);高等学校学科创新引智计划(No.B08038)

摘　　要：针对underlay认知无线电中时频重叠正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)信号的信噪比(Signal to Noise Ratio,SNR)难以估计的问题,提出了一种基于循环自相关特性的时频重叠OFDM信噪比盲估计方法.该方法提取接收信号的循环自相关函数截面中的离散谱线估计出分量信号的总功率,并结合时延和循环频率均为零时的离散谱线估计出时频重叠OFDM信号的信噪比.仿真结果表明,在无需先验信息的情况下,当SNR大于-7d B时,所提方法估计的均方误差小于0.1,并且对分量信号的功率比和频谱重叠率具有稳健性.In this paper,we propose one cyclic autocorrelation function（ CAF） based method to implement the blind signal-to-noise（ SNR） estimation over the underlay cognitive radio networks. The orthogonal frequency division multiplexing（ OFDM） is adopted here. This SNR estimator utilizes the discrete spectrum of the CAF for the received signals,whose time delay and cyclic frequency are zero. Numerical results show that the proposed method is robust to the power ratio and spectral overlapping of the composite signal without prior information. Moreover,when the SNR is greater than-7 dB,the mean square error（ MSE） for the SNR estimation is less than 0. 1.

关 键 词：认知无线电 参数估计 underlay 时频重叠 OFDM 信噪比 

分 类 号：TN911.7[电子电信—通信与信息系统]