应用抗差估计进行海底勘探实时声学定位的方法

由于海底勘探实时声学定位过程中存在大量的野值和粗差，这些不合格的观测值若不经正确处理会严重影响海底应答器的定位精度。为此，分析了附加深度约束的交会定位、基于选权迭代的差分定位及考虑声线弯曲定位等方法的应用领域和局限性，从定位精度要求及可靠性角度出发，结合海底勘探声学定位数据采集需实时定位和单一方向航行的特点，提出了一种基于抗差估计的实时声学定位方法。首先，给定观测值可能范围进行野值剔除处理；然后，基于概率统计假设方法进行粗差探测；最后，构建极值函数确定观测值权阵，通过迭代计算求得海底应答器的空间位置。模拟仿真实验和野外实际数据验证表明：该方法有效地剔除了野值和粗差，得到了最优的无偏估计；与目前实时声学定位软件中采用的最小二乘估计比较，该方法提高了海底勘探声学定位内符合精度及定位结果的可靠性，满足了放样导航船实时进行航线修正的需求，保证了海底检波器放样精度。

Real-time acoustic positioning method by appying robust estimation for seabed exploration

Due to the fact that there are a large number of burst noise and gross errors in the real-time acoustic positioning process of seabed exploration,these unqualified observations will seriously affect the positioning accuracy of seabed transponders if they are not processed correctly. This paper analyzes the application fields and limitations of intersection positioning with depth constraints,differential positioning based on weight selection iteration,and positioning methods considering sound ray bending. Toward better positioning accuracy and reliability,this paper proposes a real-time acoustic positioning method based on robust estimation,which considers the working characteristics of real-time positioning and single-direction navigation in the acoustic positioning data acquisition of seabed exploration. Specifically,the possible range of observation values is given to eliminate burst noise, and the gross errors are detected by the probability and statistical hypothesis method. Moreover,the extreme value function is constructed to determine the weight matrix of the observation values,and the spatial position of the seabed transponder is obtained through iterative calculations. The simulations and field data analysis reveal that the proposed method can effectively eliminate the burst noise and gross errors and obtain the optimal unbiased estimation. Compared with the current real-time acoustic positioning software based on least square estimation,the proposed method improves the internal coincidence accuracy of acoustic positioning in seabed exploration and the reliability of positioning results. It meets the needs of real-time route correction of a lofting navigation ship and ensures the lofting accuracy of seabed geophones.