适用于突发直扩信号盲检测的改进算法  

A Modified Algorithm for Blind Detection of the Burst DSSS Signal

作　　者：刘万贤[1] 彭华[1] 杨欣[1] 

机构地区：[1]解放军信息工程大学信息系统工程学院,河南郑州450002

出　　处：《信号处理》2013年第7期857-864,共8页Journal of Signal Processing

基　　金：国家自然科学基金(61072046)

摘　　要：提出一种改进的基于循环谱特征量的突发直扩信号盲检测算法,该算法重点研究了检测特征量的构造和信号起止点的判决问题。首先分别计算循环频率α=0截面的方差值和α=fc邻域内多个截面方差值的平均,并以两者差的绝对值作为特征量,然后分别设置信号和噪声的特征量集实时跟踪信号与噪声的变化,以自适应调整信号起始点和终止点的判决门限,准确捕获信号的起止点位置,最终实现信号的正确检测。仿真结果表明,改进算法稳健性好,判决精度高,在信噪比为-5dB时其检测概率可达90%以上。To detect the burst Direct Sequence Spread Spectrum（DSSS） signal blindly,a modified algorithm based on the feature derived from cycle spectrum is proposed.The algorithm mainly studies the construction of detection feature and the determination of the start and end points of signal.Firstly,the variance of cycle frequency α=0 profile data and the mean of variance of several profiles data close to cycle frequency α=fc are calculated respectively,and then the absolute value of difference between them is provided as the detection feature.Then,the change of signal and noise is tracked by setting corresponding feature collection in real time,which can adjust the thresholds used for the decision of the start and end points of signal self-adaptively,and the points can be captured accurately.Ultimately,the correct detection of the signal is achieved.The simulation results demonstrate that the algorithm has better robustness and higher precision of decision,and the probability of detection can reach above 90% when the signal to noise ratio（SNR） is-5dB.

关 键 词：突发直扩信号 盲检测 信号起止点 双自适应门限 

分 类 号：TN911.7[电子电信—通信与信息系统]