南海夏季海洋环境噪声与海面风速相关特性分析

Correlation property analyses of ambient noise with surface wind speed in summer of the South China Sea

海洋环境噪声是影响潜艇作战及远程目标探测和定位的重要参数,由于海洋环境噪声具有很强的时空变异性,因此一种有效的手段是通过试验数据测量和处理了解特定海区的海洋环境噪声的统计特性。本文以2013年4月30日至8月1日,南海典型海域布放海洋环境噪声测量潜标系统所收录的环境噪声为研究对象。数据处理结果表明,在整个频率范围内,海洋环境噪声与对数风速具有很好的线性关系,但环境噪声随风速变化的斜率与频率相关,在1 k Hz附近达到最大值。通过波束形成分析了海洋环境噪声的垂直指向性,并给出了"垂直方向噪声"、"水平方向噪声"和"全向噪声"与风速相关性分析结果。可以看出,在风浪噪声与远处航船噪声都有贡献的中频段,"垂直方向噪声"与海面风速的相关性好于"全向噪声"和"水平方向噪声"与海面风速的相关性,且"垂直方向噪声"随风速变化的斜率略大于"全向噪声"随风速变化的斜率。

Ambient noise is an important parameter for affecting submarine warfare, remote target detection and localization. As ambient noise has a strong spatial and temporal variability, its statistical characteristics may be obtained by data processing from the measurement data. This article is based upon the ambient noise data collected using submersible buoy system in the South Sea from April 30, 2013 to August 1. The results of data processing show that the ambient sea noise has linear relations with the logarithm of wind speed over the entire frequency region, but the slopes are markedly frequency dependent and reach maximum at 1 kHz. This paper analyzes the vertical directionality by beamforming and also gives the correlation result of ＂vertical directionality noise＂, ＂horizontal directionality noise＂ and ＂omnidirectional noise＂ with wind speed. We can see that, in the mid-frequency band which includes wind generated noise and shipping noise, the correlation of ＂vertical directionality noise＂ with wind speed is better than the correlation of ＂omnidirectional noise＂ and ＂horizontal directionality noise＂ with wind speed. And the slopes of ＂vertical directionality noise＂ with wind speed are slightly larger than the slopes of ＂omnidirectional noise＂ with wind speed.