附有平面约束的整周模糊度解算方法研究

发布时间：2018-05-16 22:05

本文选题：整周模糊度 + 约束条件　；参考：《西南交通大学》2016年硕士论文

【摘要】：在GPS定位中,整周模糊度的解算是实现精密定位的关键,快速准确的求解整周模糊度对提高定位精度,缩短定位时间都有重大的意义。通过增加约束条件,可提高单历元解算模糊度的可靠性。因此本文尝试附加平面约束条件对双差整周模糊度进行单历元解算,最后通过实验验证该算法的可行性并分析其解算效果。本文主要工作有以下几个方面：1.首先以GPS测量的基本原理为基础,重点介绍GPS相对定位技术,分析了GPS相对定位中单差、双差的定位原理及其特性,比较各种相位观测值线性组合的特点与应用；同时对GPS观测文件的预处理作了简要说明,为后面的实验方案设计和卫星数据处理做准备。2.研究了解算模糊度的相关理论和方法,对几种典型的模糊度搜索方法作了说明,如模糊度函数法,最小二乘搜索法,最小二乘降相关法(LAMBDA)等,并对它们的优缺点作了比较说明,文中主要使用最小二乘算法求解模糊度的浮点解和使用LAMBDA法进行整周模糊度的搜索。3.针对GPS单历元定位中条件数有限,浮点模糊度最小二乘解的精度差,整周模糊度难以正确固定,本文采用加入空间平面作为约束条件,利用坐标参数与模糊度参数之间的约束关系,改善浮点模糊度的解算精度,减小整数模糊度的搜索空间。文中利用多种解算方法结合约束条件对载波相位整周模糊度进行单历元求解,并且利用不同基准站下的实测数据验证平面约束条件下的模糊度解算的改进效果,数据处理中利用组合观测值在解算整周模糊度中的优势,首先固定宽巷组合的模糊度,再利用宽巷模糊度和约束条件,分别固定L1,L2模糊度,最终实现单历元定位。验证了约束条件可行后,进一步尝试双基站下的动态定位,通过增加基准站,有效增加了观测量总数,并且合理利用基准站和流动站间的基线闭合关系,把静态基准站间的解算结果,引入到动态定位,以提高整周模糊度固定的成功率和可靠性,同时也有利于解算坐标的修正。
[Abstract]:In GPS positioning, the solution of integer ambiguity is the key to realize precision positioning. It is of great significance to solve the ambiguity of whole cycle quickly and accurately to improve the positioning accuracy and shorten the positioning time. The reliability of ambiguity resolution of single epoch can be improved by adding constraint conditions. In this paper, we try to calculate the integer ambiguity of double difference by adding plane constraints. Finally, the feasibility of the algorithm is verified by experiments and the effect of the algorithm is analyzed. The main work of this paper is as follows: 1. Based on the basic principle of GPS measurement, this paper introduces the GPS relative positioning technology, analyzes the positioning principle and characteristics of single and double difference in GPS relative positioning, and compares the characteristics and applications of linear combination of various phase observations. At the same time, the preprocessing of the GPS observation document is briefly explained, which makes preparation for the later experimental scheme design and satellite data processing. In this paper, the relevant theories and methods of calculating ambiguity are studied, and several typical fuzzy degree searching methods, such as ambiguity function method, least square search method, least square reduced correlation method and Lambda method, are described, and their advantages and disadvantages are compared and explained. In this paper, the least square algorithm is used to solve the floating point solution of ambiguity and the LAMBDA method is used to search the integer ambiguity. In view of the limited number of conditions in GPS single epoch positioning, the poor precision of floating-point ambiguity least square solution, and the difficulty of fixing the integer ambiguity correctly, the spatial plane is used as the constraint condition in this paper. By using the constraint relation between coordinate parameter and ambiguity parameter, the precision of solving floating-point ambiguity is improved, and the searching space of integer ambiguity is reduced. In this paper, a single epoch is used to solve the integer cycle ambiguity of carrier phase by using various methods combined with constraint conditions, and the improved results of ambiguity resolution under plane constraints are verified by the measured data under different reference stations. In data processing, the advantage of combined observation value in solving integer ambiguity is used. Firstly, the ambiguity of wide roadway combination is fixed, then the ambiguity of L _ 1 / L _ 2 is fixed by using wide lane ambiguity and constraint condition, and the single epoch location is finally realized. After verifying the feasibility of the constraint condition, we further try to locate dynamically under the double base station. By increasing the reference station, we can effectively increase the total number of observations, and make rational use of the closed baseline relationship between the reference station and the mobile station. The results of calculation between static reference stations are introduced to dynamic positioning to improve the success rate and reliability of the fixed integer ambiguity, and at the same time to improve the correction of the solution coordinates.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：P228.4

【相似文献】