界面噪声声压与质点振速的时空相干特性

Spatial-temporal coherence of acoustic pressure and particle velocity in surface-generated noise

海洋环境噪声矢量场空间相干特性与矢量传感器阵的性能密切相关.应用海洋混响相干特性分析方法应用海洋混响相干特性分析方法研究了均匀半无限空间界面噪声声压与质点振速的空间相干特性问题,得到了相干特性的解析表达式.研究结果表明,界面噪声场的空间相干特性相比于均匀各向同性噪声场要复杂得多,其相干特性在空间上是不均匀的,并且与噪声源的指向性也有复杂的关系.虽然只给出噪声源无指向性和余弦的垂直指向性2种情况下场的相关系数,但该文的研究方法可以推广到任意指向性噪声源的场的相干特性的分析中.当获得了噪声场空间相干特性的解析解时,矢量水听器输出信噪比增益可以很容易地给出,同时对矢量水听器基阵的布阵及应用也具有重要的意义.

Performance of an acoustic vector sensor array is highly affected by the spatial coherence of the ambient noise vector field. The spatial coherence of the acoustic pressure and the particle velocity of the surface-generated noise in a homogeneous half-space was analyzed by the method of cornelation analysis in ocean reverberation. Ana- lytical expressions of the correlated coefficients were obtained. With respect to isotropic and homogeneous noise, spatial coherence of such noise was much more complicated. It is inhomogeneous in space and has a complex rela- tionship to the directivity of the noise source. Although only the coefficients of fields consisting of omnidirectional sources or perpendicular directional sources with a cosine function were given, the method could be extended to an- alyze noise from any direction. With explicit solutions of spatial coherence, the signal-to-noise ratio （SNR） output of an acoustic vector sensor could easily be found. This method should also improve the design and application of acoustic vector sensor arrays.