基于单压差式矢量水听器的测向算法

Direction Finding Method Based on Single Pressure Gradient Vector Hydrophone

摘要:

对于单个压差式矢量水听器，如果其直径波长比不满足工程近似条件，使用复声强法进行方位估计时，直接通过反正切运算进行角度计算会产生较大的测向误差，而使用修正声强法校正其阵列流型则需要较高的信噪比。给出了单压差式矢量水听器直径波长比的应用上限，并使用瞬时频率方差加权法，利用目标线谱与背景噪声两者瞬时频率能量起伏稳定性的差异，为频带内具有不同瞬时频率方差的频率单元赋予不同权值，以此抑制环境噪声对目标声源的影响，改善修正声强法测向的信噪比性能。仿真结果验证了算法的有效性和优越性。

关键词:压差式矢量水听器;方位估计;直径波长比;修正声强法;瞬时频率方差加权

Abstract:

When the diameter to wavelength ratio does not meet the engineering approximation conditions， using the complex sound intensity method directly for azimuth estimation of a single pressure gradient vector hydrophone results in significant direction finding errors. While using the modified sound intensity method for azimuth estimation requires a higher signal-to-noise ratio（SNR）. This paper provides an upper limit for the application of the diameter-to-wavelength ratio of a single pressure gradient vector hydrophone. The instantaneous frequency variance weighing method is used. The difference in instantaneous frequency energy fluctuation stability between the target line spectrum and background noise is utlized to assign different weights to frequency units with different instantaneous frequency variances within the band. Thus，the impact of environmental noise on the target sound source is suppressed，and the SNR performance of the modified sound intensity method for direction finding is improved. Simulation results verifies the effectiveness and superiority of the algorithm.

Key words:pressure gradient vector hydrophone;azimuth estimation;diameter-to-wavelength ratio;modified sound intensity method;instantaneous frequency variance weighting method