精密定位若干误差分析及实时精密单点定位研究

发布时间：2018-05-28 04:20

本文选题：GPS + 实时精密单点定位　；参考：《长安大学》2013年硕士论文

【摘要】：精密定位中的误差项是影响定位精度的最直接也是最主要的因素。随着对定位精度要求的不断提高，需要建立更加准确有效的误差改正模型。本论文对影响精密定位精度的卫星轨道插值、接收机天线整流罩影响以及多路径效应等误差项展开了较为深入的研究。另外，实时精密单点定位技术（Real-time Precise Point Positioning，简称RT-PPP）已成为当前GNSS领域的研究热点，也将是目前乃至未来实时高精度动态定位的主要技术手段之一。本论文针对实时精密单点定位技术存在的关键问题，重点研究了基于区域IGS站网实时估计钟差的实时PPP方法，以及在此基础上提出的改进方法——一种无需精密钟差的实时PPP方法。论文的主要成果和贡献如下： 1、针对精密定位中的轨道插值误差，定量分析了6种插值方法在GPS轨道内插中的精度，得出6种方法在结果上的一致性和原理上的等价性，都在取9阶时其内插精度都为最优，并且内插得到的标准化轨道完全可以满足后续解算的要求。 2、证明了6种一般内插方法不适合低轨卫星如GOCE卫星的轨道和速度插值，最后研究提出了一种高精度GOCE卫星几何速度的插值方法，，该方法大大提高了速度插值精度和可靠性。运用本文方法获取的高精度几何法轨道速度，将为后续基于GOCE卫星几何法轨道的重力场恢复提供强有力的支撑。 3、总结得出接收机天线整流罩是通过天线相位中心的变化来影响定位精度，得到了整流罩对天线相位中心的影响与高度角成正耦合关系的结论，并比较分析了不同类型天线整流罩对相对定位和PPP精度的影响，给出了定位计算时整流罩选择问题的建议。 4、研究了在精密定位中常被忽略的多路径效应的影响，通过伪距减载波方法（CMC）定量给出了中国区域内5个IGS测站的多路径影响水平，并运用最小均方自适应算法（LMS）对原始多路径误差进行滤波处理，结果证实新滤波算法的误差改正率维持在80%以上，这有利于提高后续定位的精度。 5、提出了基于区域IGS网估计卫星钟差的实时精密单点定位方法，用该方法估计得到的钟差与IGS精密钟差产品具有较好的一致性，互差的RMS优于0.1ns，利用该方法求解出的钟差，可以获得厘米级的实时PPP精度。 6、指出了基于区域IGS网估计卫星钟差的实时精密单点定位方法的一些缺点，提出了一种无需精密钟差的实时精密单点定位方法，结果表明新方法不仅对参考站数量的要求较低，而且平均精度优于同等条件下估计卫星钟差的PPP方法，精度提高近28.8%。
[Abstract]:The error term in precision positioning is the most direct and main factor that affects the positioning accuracy. With the improvement of positioning accuracy, a more accurate and effective error correction model is needed. In this paper, the error terms such as satellite orbit interpolation, receiver fairing and multipath effect, which affect the precision of positioning, are studied deeply. In addition, Real-time Precise Point Positioning, (RT-PPP), a real-time precise single point positioning technology, has become a hot research topic in the field of GNSS, and will be one of the main technical means of real-time and high-precision dynamic positioning in the future. Aiming at the key problems of real-time precise single point positioning technology, this paper focuses on the research of real-time PPP method based on real-time estimation of clock error in regional IGS network. On the basis of this, an improved method, a real time PPP method without precise clock error, is proposed. The main achievements and contributions of the paper are as follows: 1. Aiming at the orbit interpolation error in precision positioning, the accuracy of six interpolation methods in GPS orbit interpolation is quantitatively analyzed, and the consistency of the results and the equivalence in principle of the six interpolation methods are obtained. And the normalized orbit can meet the requirements of the subsequent solution. 2. It is proved that six general interpolation methods are not suitable for orbit and velocity interpolation of Leo satellites such as GOCE satellites. Finally, a high precision interpolation method for geometric velocity of GOCE satellites is proposed, which greatly improves the accuracy and reliability of velocity interpolation. The high precision orbital velocity obtained by the method in this paper will provide a strong support for the subsequent gravity field recovery based on the GOCE satellite geometric orbit. 3. It is concluded that the fairing of the receiver affects the positioning accuracy by the change of the antenna phase center, and the effect of the fairing on the antenna phase center is positively coupled with the height angle. The effects of different types of radome on relative positioning and PPP accuracy are compared and analyzed. Suggestions on the selection of fairing in positioning calculation are given. 4. The influence of multipath effect, which is often neglected in precision positioning, is studied, and the multipath influence level of five IGS stations in China is quantitatively given by using pseudo-range carrier subtraction method. The least mean square adaptive algorithm (LMS) is used to filter the original multipath error. The results show that the error correction rate of the new filtering algorithm is above 80%, which is helpful to improve the accuracy of the subsequent location. 5. A real time precise single point positioning method based on regional IGS net to estimate satellite clock error is proposed. The clock difference estimated by this method is in good agreement with that of IGS precision clock difference product. The RMS with mutual difference is better than 0.1 ns, and the clock difference calculated by this method is better than that obtained by this method. Real-time PPP accuracy of centimeter level can be obtained. 6. Some shortcomings of the real-time precise single point positioning method based on regional IGS net estimation of satellite clock error are pointed out, and a real-time precise single point positioning method without precise clock error is proposed. The results show that the new method not only requires less reference stations. And the average accuracy is better than the PPP method of estimating satellite clock error under the same conditions, and the accuracy is improved by nearly 28.8.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228

【引证文献】