采用峰值平均功率比的低信噪比水下多目标检测方法  

A Detection Method for Underwater Multiple Source under Low Signal-to-Noise Ratio Using Peak-to-Average Power Ratio

作　　者：王静[1] 黄建国[1] 侯云山[1] 

机构地区：[1]西北工业大学航海学院,西安710072

出　　处：《西安交通大学学报》2012年第2期124-129,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(60972152);航空科学基金资助项目(2009ZC53031)

摘　　要：针对信息论准则多目标检测方法在低信噪比水下应用环境中不能正确检测目标源个数的问题,提出了基于峰值平均功率比(PAR)的多目标检测方法(PARTC).该方法首先使用相关矩阵特征向量对水下基阵接收数据加权计算阵列加权输出数据,然后计算加权输出数据的PAR并对PAR进行降序排列,由于纯噪声加权输出数据的PAR呈线性分布,并且其平均梯度与快拍数无关,存在信号时的加权输出数据的PAR梯度大于纯噪声加权输出数据的PAR梯度,因此可根据该信息判定信号源个数.八元阵的仿真结果表明,PARTC方法在在低信噪比、小快拍和小信号源夹角情况下的多目标正确检测概率大于信息论准则和最小描述长度多目标检测方法,并且运算量适中,水下应用前景广阔.A new multiple source detection threshold criterion based on peak-to-average power ratio（PAR） is proposed to solve the problem that multiple source detection methods based on information criterion cannot correctly estimate the number of sources under low signal-to-noise ratio in underwater environment（PARTC）.The underwater array receiving data are weighted using the eigenvectors of the data correlation matrix,and the weighted data are calculated.Then,PARs of the weighted data are computed,and then sorted in a descend order.The number of sources can be estimated using the information that the PARs of pure noise have a linear distribution,and that the average grad of PARs is independent of snapshots,and when there exists signals the grad of signal PARs will be larger than the average grad of pure noise PARs.Simulation results on an 8-elements array show that the probability of correct detection of PARTC is larger than those of both the Akaike information criterion method and the minimum description length method under the conditions of low signal-to-noise ratio,small snapshots and closely spaced sources,while the calculation of PARTC is not expensive.Thus PARTC has board applications in underwater environment.

关 键 词：水下多目标 检测 低信噪比 峰值平均功率比 

分 类 号：TN911[电子电信—通信与信息系统]