长基线定位系统高精度阵型标定方法

为解决长基线定位系统传统标定方法中受垂直方向声速变化剧烈而导致的标定精度差、逐个声信标交汇标定效率低、跟踪定位阶段采用不同声信标基准对目标解算不一致的问题,本文提出了一种高精度相对阵型标定方法,通过水下声信标的互测距信息构建观测模型改进了传统标定方式。理论分析表明,采用该方法水平方向上能够获得与测距等量级的标定精度,有效地提高了标定效率,采用不同的声信标基准目标解算结果一致,在深海作业中优势明显。通过浅水试验结果可以看出该方法水平方向上的标定精度能达到和测距等量级的毫米量级精度,和传统标定方法相比提高了一个数量级,在提高标定精度的同时降低了作业复杂度,采用本文的标定结果获得的目标定位结果更接近于GPS输出,具有良好的工程应用价值。 

A high precision calibration method for long baseline acoustic positioning systems

This paper gives the theory and formulas to show that high precision calibration for underwater beacon arrays in long baseline (LBL) is the basement of high precision target tracking. The traditional method calibrates beacon separately using trilateration which is highly affected by survey trajectory and sound velocity profile. The performance is undesirable with bad precision and low efficiency. To solve this problem, this paper proposes a calibration method for relative calibration using the distances measured between undersea beacons and depths of each beacons to form observation equations. The positions of beacons are calibrated relatively by the distances and the depth measurements. The precision of calibrated beacons is equal to the precision of distance measurements with high efficiency and low complexity for operation. The analysis and experimental results show this method has better precision of calibration than traditional method, the horizontal precision is determined by the precision of distance measurement which is less than decimal meter and the depth precision is determined by the precision of pressure sensor. This method also reduces the calibration time efficiently. Compared with traditional method, this method can reduce the calibration time nearly 10 times, especially in deep sea and large scale operation. This paper also analyses the different performance in tracking target between traditional method and the method we proposed, the effect of sound velocity profile and beacon array topology. This method can be widely used for LBL acoustic positioning systems, which has great value in ocean engineering.