单矢量水听器的高分辨目标方位跟踪算法研究

根据单矢量水听器自身具有阵列流型的特点,提出了适用于对目标保持连续跟踪的空域预滤波MUSIC算法。通过调整滤波器通带中心角使其保持在目标估计方位角附近,可以消除滤波器通带中心角偏离目标真实方位角时传统预滤波MUSIC算法产生的目标方位估计误差。仿真结果表明,改进预滤波MUSIC算法可以减小甚至消除低信噪比情况下目标方位估计存在的较大误差。海试数据结果表明,阵元域MUSIC和改进预滤波MUSIC都可实现对单频脉冲信号和线性调频信号的目标方位估计,且估计结果与GPS舰位推算结果一致,但改进预滤波MUSIC算法主瓣更尖锐。对宽带航船噪声处理结果显示,改进预滤波MUSIC算法使单矢量水听器在存在目标干扰时的探测距离从2 km提升到了5 km,验证了改进预滤波MUSIC算法可实现弱目标情况下的高分辨目标方位跟踪。

Research on High-resolution Target Azimuth Tracking for A Single Vector Hydrophone

Taking into account the characteristic of single acoustic vector sensor, MUSIC(multiple signal classification) algorithm of spatial pre-filtering approach was developed. By adjusting the angle of the filter passband center in the vicinity of the target estimated azimuth, traditional pre-filtering MUSIC algorithm produces estimation error was removed. Simulation indicates that the improved pre-filtering MUSIC algorithm can reduce or even eliminate the low signal-to-noise ratio(SNR) greater presence DOA Estimation Error. Finally, the sea-trial data was processed using the conventional MUSIC and improved pre-filtering MUSIC. Results show that both algorithms can achieve DOA estimation for single-frequency pulse signal and chirp signal, and the estimated results are consistent with the GPS ship reckoning. But the main lobe of the improved pre-filtering MUSIC algorithm are sharper. Broadband noise processing results show that detection distance upgrade from 2km to 5km in the presence of a target interference for a single vector hydrophone, which indicates that the improved pre-filtering MUSIC algorithm can be achieved high-resolution target tracking in low SNR.