中文摘要：

对于深海近水面声源产生的声场,处于较大深度处的接收器在一定水平距离范围内能接收到直达波.2014年在某深海海域进行的水声考察实验中,应用深度为140 m的拖曳声源发射实验信号,布放在水下3146 m深处的矢量水听器成功地接收到了直达波信号.本文应用射线理论,分析了深海直达波区域声场的传播特性,得出了水平振速与垂直振速的传播损失与声线到达接收点处的掠射角以及收发水平距离之间的关系.在以上分析的基础上,提出了一种利用水平振速与垂直振速的能量差估计声源距离的方法,并结合2014年实验数据对实验中两条航线上8 km范围内的目标声源进行了测距,测距结果与目标的GPS数据符合得较好.

英文摘要：

The receiver at larger depth can receive the direct-arrival signal from a shallow source in a certain range in deep water.During a deep-water experiment conducted in 2014,a vector sensor located at a depth of 3146 m received the direct-arrival signals from the transducer towed at about 140 m depth by the source ship.In this paper,the propagation properties of the sound field in the direct-arrival zone in deep water are studied based on the ray theory and subsequently a source-range-estimation method is proposed.In the direct-arrival zone,the arrival angle is one of the most important properties of sound field,and the sound field is mainly composed of the contributions of a direct ray and a surface-reflected ray.The theoretical analysis and simulation results show that the amplitudes of horizontal particle velocity and vertical particle velocity are related to the mean arrival angle of the direct ray and the surface-reflected ray,and the larger the arrival angle,the greater the vertical particle velocity is,but the weaker the horizontal particle velocity is.Furthermore,the energy difference between horizontal particle velocity and vertical particle velocity can be approximately expressed by a monotonic function of the arrival angle,which varies fast with the horizontal distance between source and receiver.This property is applied to the estimation of source range.The analysis of the experimental data shows that the estimated source ranges are consistent with the GPS ranges within the range of 8 km,and the mean relative error of source range estimation is within 10%.