基于GNSS-A的海底目标高精度定位算法研究

Research on Seafloor Target High-Precision Positioning Algorithm Based on GNSS-A

关键词:  全球导航卫星/声学定位  海底目标定位  声学换能器  最小二乘法  声线跟踪

Key words:  GNSS-A  seafloor target position  acoustic transducer  least square method  sound ray tracking

摘要:

为提高海底目标垂直方向的定位精度，在分析全球导航卫星/声学定位（Global Navigation Satellite System-Acoustic，GNSS-A）基本原理的基础上，提出基于动态观测的海底目标声学定位算法。针对动态观测中产生的双程传播时延问题，将其发射和接收过程分别考虑，并利用最小二乘（Least Squares，LS）法解算圆形对称观测数据，消除绝大部分系统误差和粗差对水平定位精度的影响；结合水平解算结果、高精度声学测距信息和实测声速剖面信息，开展声线跟踪（Sound Ray Tracking，SRT）并构造迭代，进一步减弱垂直方向误差，提高海底目标点的垂直定位精度。南海实验证明，采用本文方法可以有效减小声速误差对测距精度的影响，明显提高海底目标在垂直方向上的定位精度。

Abstract:

In order to improve the vertical positioning accuracy of seafloor target, the basic principle of Global Navigation Satellite System-Acoustic (GNSS-A) is analyzed, and the acoustic positioning algorithm of submarine targets based on dynamic observation is given.Aiming at the problem of two-way propagation delay in dynamic observation, the transmitting and receiving processes are considered separately, and the Least Squares (LS) method is used to solve the circular symmetric observation data to eliminate the influence of most systematic errors and gross errors on the horizontal positioning accuracy.Combined with the results of horizontal calculation, the high-precision acoustic ranging information and measured sound velocity profile information, the Sound Ray Tracking (SRT) is carried out and iteration is constructed to further reduce the vertical direction error and improve the vertical positioning accuracy of seafloor target points.The experiment in the South China Sea proves that the proposed method can effectively reduce the influence of sound velocity error on the ranging accuracy, and obviously improve the positioning accuracy of seafloor targets in the vertical direction.