不同压强深度转化模型构建的声速剖面对水下定位的影响

The Impact of Constructing Sound Velocity Profiles Through Different Pressuredepth Conversion Models on Underwater Positioning

高精度水下声学定位需要高精度的声速剖面,目前使用声速剖面仪、温盐压仪测得的声速剖面中深度信息由压强转换得到。为解决高精度水下目标定位所需的高精度声速剖面问题,本文研究了压强深度转换模型对于水下目标定位精度的影响。由EOS-80海水状态方程推导的压强深度转换模型较为常用,但其考虑的影响因素较少。相反,TEOS-10海水状态方程则综合了温度、盐度、压强等多重因素,计算方法更严密。本文在全球范围内选择10组Argo浮标观测的CTD数据,并使用常梯度声线跟踪方法对使用EOS-80和TEOS-10两种模型构建的声速剖面进行水下声学定位模拟。结果表明,使用2种压强深度转换模型构建的声速剖面在水下目标定位中存在最大为4.1 cm的互差。因此,在高精度的水下目标定位中,建议采用更精确的TEOS-10压强深度转换模型构建声速剖面。

High-precision underwater acoustic positioning requires high-precision sound speed profiles.Currently,the depth information in the sound velocity profile,measured by the sound velocity profiler and the temperature salt pressure instrument,is calculated using the pressure depth conversion function.In order to solve the problem of high-precision underwater target positioning requiring high-precision sound velocity profiles,this study investigated the impact of different pressure depth conversion models on underwater target localization.The pressure depth conversion model derived from the EOS-80 seawater state equation is commonly used,but it considers fewer influencing factors.The pressure depth conversion model derived from the TEOS-10 seawater state equation considers factors such as temperature,salinity,and pressure that affect pressure depth conversion,and the model has a more rigorous calculation method compared to the EOS-80 model.This study selected 10 sets of CTD data collected by Argo buoys worldwide,and used the sound velocity profiles constructed by the two pressure depth conversion models mentioned above for underwater target positioning.During the positioning process,constant gradient sound line tracking was used to calculate geometric distance.The results showed that the sound velocity profiles constructed by two pressure depth conversion models produced a maximum difference of 4.1 cm when used for underwater positioning.In high-precision underwater target positioning,a more rigorous TEOS-10 pressure depth conversion model should be used to construct sound velocity profiles.