随机共振法估计二水听器时延差

针对二元阵航船目标方位估计问题,提出了一种基于随机共振滤波的航船辐射噪声双水听器时延差估计方法。设计了一种随机共振滤波器,提取航船螺旋桨旋转噪声在水听器接收信号中出现的本地时间,并通过滤波结果的互相关来估计目标辐射噪声分别到达两个水听器的时延差。在5 dB的输入信噪比下进行200次仿真,提出方法时延估计的归一化均方误差要低于互谱方法一个数量级。对于海试中的非合作航船,提出的方法可以在1 km距离下准确估计出目标辐射噪声到达双水听器的时延差,从而为在二元阵上实现对航船目标的准确测向提供基础。 

The estimation of the time-delay difference for the binary hydrophone by the stochastic resonance

For the direction estimation of the ship target by the binary hydrophone array,a time-delay difference estimation method of the ship radiation noise based on the stochastic resonance is proposed.A stochastic resonance filtering is designed and used to extract the local time when the ship propeller rotation noise appears in the signal received by the binary hydrophone array.Then the cross-correlation of the filtering results is used to estimate the time-delay difference between the ship radiation noise reaching the two hydrophones.By 200 times simulation with an input signal to noise ratio of 5 dB,the normalized mean square error of the time-delay difference estimation of the proposed method is an order of magnitude less than the method based on the cross-spectrum.The experiment results on the sea have shown that the time-delay difference between the ship radiation noise reaching the two hydrophones can be estimated accurately by the proposed method with a distance of 10 km.By the proposed method,the direction of the ship propeller rotation noise can be estimated accurately by the binary hydrophone array.