一种基于相关积分的互谱WVD目标方位估计方法

A method of target DOA estimation based on correlation integral and cross spectrum WVD

针对水下高速运动目标的被动跟踪问题,将魏格纳-威尔分布(Wigner-Ville Distribution,WVD)算法与互谱法相结合,构建了一种矢量信号处理框架下的目标方位估计方法——基于相关积分的互谱WVD算法。该算法利用了矢量水听器声压通道与振速通道信号的相关特性,首先通过计算两者的互相关函数来提取目标信号的特征信息,然后通过短时积分与傅里叶变换将互相关函数从时域转换到频域,最后在频域提取信号的特征参量,并进行方位估计。仿真研究表明,当目标处于远距离且低速运动时,所提算法的方位估计性能与互谱声强法基本一致;而当目标处于近距离且高速运动时,算法的方位估计性能大大优于互谱声强法。

Considering the problem of passively tracking for high speed underwater moving targets, a method of target DOA estimation based on instantaneous correlation integral and cross spectrum WVD is proposed in the framework of vector signal processing. The proposed algorithm utilizes the correlation features of the vector sensor. The basic idea is firstly to compute the instantaneous correlation of acoustic signals received by vector hydrophone; then to obtain the spectrum through short time integral of the correlation and Fourier Transform; and finally to estimate the direction of target by cross spectrum acoustic intensity method. Simulation results show that the performance of the proposed algorithm is in accordance with that of cross spectrum acoustic intensity algorithm when the target is at long distance and at low speed; however, the former performs remarkably better than the latter when the target is at short distance and at high speed.