浅海环境噪声垂直相关提取海底反射参数

Extracting bottom reflection parameters from the vertical correlation of ambient noise in shallow water

分析小掠射角海底反射特性与浅海环境噪声场垂直相关的关系,从而提取表征海底反射的参数.对某海域浅水区观测的海洋环境噪声数据进行垂直相关特性研究,并用于反演海底参数.鉴于海底参数之间存在耦合,采用分步反演的方法:首先利用曲线拟合或经验公式的方法获取海底反射相位,然后再反演海底反射幅度,最后将反演结果用于同海区的爆炸声声场预报,预报结果和试验测量相比,相对误差均小于10%.根据本文建立的噪声场垂直相关模型提取小掠射角海底反射参数,不需要限定特定的海底模型,反射损失中还包括界面散射的影响,可以有效地预报声场.

A method is introduced to extract reflection characteristics at smaller angles from the vertical correlation of surface-generated noise in shallow water, since the relationship of the two is analyzed. By presenting the vertical correlations of the ambient noise data measured in one experiment in China, the geo-acoustics parameters are estimated. It is shown that these parameters are mutual coupled, therefore a segmentation inversion algorithm has been developed. The reflection phase shift is obtained according to curve fitting or empirical expressions, while the reflection energy is inferred subsequently. The simulation calculated using the inverted geo-acoustic parameters is in good agreement with the explosive sources measurement. There is a discrepancy of about 10% in the prediction values. It is effective for acoustic field prediction by extracting bottom reflection parameters from the noise vertical correlation. The advantage of using reflection parameters is not limited. In addition, it is simple and precision to predict acoustical field, as a result of containing interface scattering in the reflection loss.