南海深海体积混响及散射特性试验研究

深海中存在着众多的不均匀"水团"、分层、深海生物圈以及海底逸出气泡等,这些散射体对入射声信号的散射构成了深海体积混响。通过测量获取深海水体散射目标的散射强度,研究不同海区不同时间的体积混响,对进一步认识深海声学特性具有重要的作用,也有助于主动声呐系统的性能预报。从深海中的主要散射体的组成、分类及其特征出发,介绍了一种深海体积混响及散射特性的研究方法。通过垂直向下发射窄波束测量各个深度层上的散射强度,用直观的声学图像显示强度值。构建试验系统在南海进行了深海试验,通过处理和分析测量数据发现,深度100 m以内的鱼类和处于深海散射层的海洋生物是深海体积混响的主要贡献者。

Experimental study of deep-sea volume veverberation and scattering characteristics in the South China Sea

There are many uneven "water masses", layers, deep-sea creatures and seabed overflow bubbles in deep sea, the scattering of incident acoustic waves on these scatterers constitutes the deep sea volume reverberation. A experimental study of volume reverberation in different sea and different times by measuring scattering strength of deep sea water contributes to a better understanding of the acoustic characteristics of deep sea. From the composition, classification, and characteristics of the main scatterers in deep sea, this paper introduces a research method for deep-sea volume reverberation and scattering characteristics. The scattering strength of each deep layer is measured by transmitting acoustic signal with vertical downward narrow beam and displaying the intensity value of scattering in acoustic image. The system has been tested in the South China Sea, and studies reveal that fishes within 100 meters of depth and the deep-sea creatures in the deep scattering layer are the major contributors to the volume reverberation.