高频单历元GNSS动态差分定位技术研究

发布时间：2018-04-15 18:01

本文选题：GNSS + 动态定位　；参考：《山东科技大学》2017年硕士论文

【摘要】：近十几年来,四大卫星导航系统在不断、快速的向前发展。多系统的出现将会有利于改善单一系统单独定位时出现的部分时刻可视卫星数目较少,卫星几何结构差的状况。由于GNSS差分技术可以获得高精度的定位结果,使其在高精度的导航定位中有着广泛的应用。单历元定位结果的精度虽然低于多历元定位结果,但是由于现代测量技术对效率性的要求越来越高,单历元定位的应用将会更加广泛。因此,本论文就动态情况下的单历元定位算法进行了较为详细的研究。论文主要进行了如下几方面的研究:(1)分析了多系统GNSS定位的原理,对多系统GNSS双差观测方程进行了较为详细的推导。并分析了不同随机模型对伪距双差和载波双差定位结果的影响,实验结果表明基于高度角和信噪比的随机模型的定位结果要优于等权随机模型的定位结果。(2)研究了动态定位中模糊度的单历元快速有效地固定方法,提出了一种新的模糊度固定方法。这种方法首先在两周的范围内搜索宽巷模糊度,然后再根据观测方程之间的关系来固定基础模糊度。并且结合实例分析了信噪比大小对宽巷模糊度固定的影响,实验结果显示信噪比越大,模糊度解算的精度通常情况下也会越高。随后提出了一种基于信噪比大小选星的部分模糊度搜索方法,并采用实测数据对该方法进行分析,实验结果表明使用该算法可以极大地提高模糊度的解算效率。(3)对中短基线情况下单历元动态定位方法进行了研究,分析了在前后历元模糊度传递过程中更换参考卫星的问题,使用“映射”矩阵将前一个历元的模糊度传递到当前历元,可以有效地避免模糊度的重新初始化。分析了基于抗差估计的固定错误模糊度剔除及粗差处理方法,利用抗差估计可以有效地降低粗差对定位结果的影响。并对几种常用的周跳方法进行简单介绍,多种方法的联合使用可以有效地探测出周跳,提高模糊度传递过程中的正确性。(4)以实测数据对本文的单历元定位方法进行可行性和精度分析,实验结果显示本文所研究的方法在中短基线定位中有较高的定位精度。(5)对自主研发的移动测量系统软件VsursPos1.0进行介绍,该软件可实现OEM格式的原始数据解码和GNSS单历元差分定位与测速。
[Abstract]:In the past ten years, the four major satellite navigation systems have been developing rapidly and continuously.The appearance of multi-system will help to improve the situation that the number of visualized satellites at partial time is less and the geometry structure of satellites is poor when the single system is located separately.Because GNSS differential technique can obtain high precision positioning results, it has wide application in high precision navigation and positioning.Although the accuracy of single epoch positioning results is lower than that of multi-epoch positioning results, the application of single epoch positioning will be more and more extensive because of the higher and higher efficiency requirements of modern measurement technology.Therefore, in this paper, the single epoch location algorithm is studied in detail.This paper mainly studies the following aspects: 1) the principle of multi-system GNSS positioning is analyzed, and the two-difference observation equation of multi-system GNSS is deduced in detail.The influence of different random models on the pseudo-range double difference and carrier double difference localization results is also analyzed.The experimental results show that the localization results of random model based on height angle and SNR are better than those of equal weight random model.A new method for fixing ambiguity is proposed.Firstly, the ambiguity of wide lane is searched in the range of two weeks, and then the basic ambiguity is fixed according to the relationship between observation equations.The effect of SNR on the ambiguity of wide roadway is analyzed with an example. The experimental results show that the greater the SNR, the higher the precision of ambiguity resolution.Then, a partial ambiguity search method based on SNR is proposed, and the method is analyzed by the measured data.The experimental results show that the algorithm can greatly improve the efficiency of ambiguity resolution. (3) the dynamic location method of order epoch in the case of short and medium baselines is studied, and the problem of replacing reference satellites in the process of ambiguity transmission of the front and rear epoch is analyzed.The ambiguity of the previous epoch can be transferred to the current epoch by using the "mapping" matrix, which can effectively avoid the reinitialization of the ambiguity.Based on robust estimation, fixed error ambiguity elimination and gross error processing are analyzed. Robust estimation can effectively reduce the influence of gross error on location results.Several commonly used cycle slip methods are briefly introduced. The combined use of various methods can effectively detect cycle slips.To improve the accuracy of ambiguity transmission. 4) to analyze the feasibility and accuracy of the single epoch positioning method based on the measured data.The experimental results show that the method studied in this paper has a high positioning accuracy in the short and medium baseline positioning. It introduces the mobile measurement system software VsursPos1.0, which is developed by ourselves.The software can decode the original data in OEM format and GNSS single epoch differential positioning and velocimetry.
【学位授予单位】：山东科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P228.4

【参考文献】