时延匹配加权的舷外异常噪声源曲面投影定位方法

对现有的"滤波-时延估计-双曲面定位"的声源定位方法进行改进。结合经验模态分解消噪方法和广义平均幅度差函数时延估计方法,利用能量分布准则和频谱一致性准则进行源信号本征模态函数筛选和信号重构,提取多组分析信号求取时延,并利用时延匹配准则对真实时延值进行筛选和加权处理。考虑水听器贴近壳体布放,对壳体进行建模,并按照象限投影到平面再进行双曲线定位。分别进行模型系泊及航行实验,实验结果表明,改进后的定位方法有更高的定位精度,且减小了时延估计误差造成的定位精度影响。

Outboard abnormal noise source localization method with curved surface projection based on time delay matching and weighting criterion

An improved localization method consisting of ‘filtering-time delay estimation-hyperbolic localization’ is proposed. Combining the Empirical Mode Decomposition(EMD) and weighted average magnitude difference function time delay estimation method, the original signals are decomposed into Intrinsic Mode Function(IMF) components,and energy distribution criterion and spectrum consistency criterion are used to select IMFs which can represent the physical characteristics of source signal. Then applying several sets of signals to estimate the time delay, and a vector matching criterion is proposed to select the correct time delay estimation. Considering the hydrophones location, a shell model is established and projected to plane according to quadrant before hyperbolic localization. Results of mooring and sailing tests show that the proposed method improves the localization accuracy, and reduces the influence caused by time delay estimation errors.