【作者】 刘涛；

【导师】 姜维；

【作者基本信息】 北京交通大学 ， 控制工程（专业学位）， 2022， 硕士

【摘要】 基于卫星导航系统的位置服务可以应用于交通运输领域的各个方面,高精度导航定位需求逐渐增加。传统的差分定位技术能够满足定位需求,但是差分技术需要布设一定密度的差分基站,不利于降低建设成本。精密单点定位(Precise Point Positioning,PPP)使用单台卫星接收机便可获得较高精度的测量结果,既可以保证定位精度,又可以减少差分基站的使用。交通行业环境复杂多变,卫星定位系统易受隧道、城市建筑物的影响,导致可见卫星数减少,卫星定位无法满足可用性和连续性的要求。区域导航系统是一种类似于卫星定位系统的地面辅助定位系统,可以在卫星信号被遮挡场景下,辅助卫星定位系统,提高定位精度和定位连续性。因此,为进一步提高精密单点定位的定位精度和收敛速度,本文研究了精密单点定位模糊度固定方法;为有效解决卫星信号被遮挡环境下定位可用性和连续性问题,本文研究了区域导航系统辅助的精密单点定位方法。论文主要工作包括:(1)总结了精密单点定位基本流程,分析了精密单点定位的主要误差来源及改正模型,在单差无电离层PPP模型的基础上,构建了基于模糊度浮点解的扩展卡尔曼滤波算法,实现运动状态的在线估计。(2)分析了精密单点定位模糊度非整数特性的原因,研究了逐级模糊度固定方法,先固定宽巷模糊度,再固定窄巷模糊度,最后固定星间差分无电离层模糊度,验证并分析了精密单点定位模糊度固定的定位性能。(3)研究了区域导航系统的载波相位定位方法,基于单差载波相位观测量,设计了区域导航系统/精密单点定位紧组合定位方法,验证并分析了不同可用卫星数量下紧组合系统的定位性能。(4)设计并开发了基于C#语言的卫星/区域导航系统组合定位软件,分析了软件的功能需求和界面需求,并利用实验数据验证了软件的精密单点定位、精密单点定位模糊度固定以及区域导航系统/精密单点定位紧组合定位三种定位算法。实验结果表明,采用逐级模糊度固定方法,精密单点定位固定解相较于浮点解,收敛时间由800s降为750s,北向误差RMS由0.053m降为0.019m,东向误差RMS由0.09m降为0.063m。在可用卫星数不满足定位条件的情况下,区域导航系统/精密单点定位紧组合定位方法水平方向误差在30cm以内,能够保证信号遮挡环境下定位的可用性。图51幅,表9个,参考文献63篇。更多还原

【Abstract】 The location service based on satellite navigation system can be applied to all aspects of transportation,and the demand for high-precision navigation and positioning services is increasing gradually.The traditional differential positioning technology can meet the positioning requirements,but it needs to deploy a certain density of differential base stations,which is not conducive to reducing the construction cost.Precise Point Positioning(PPP)uses a single satellite receiver to achieve high-precision measurement results,which can not only ensure positioning accuracy,but also reduce the use of differential base stations and reduce construction and maintenance costs.The traffic environment is complex and changeable,and the satellite positioning system is easily affected by tunnels and urban buildings,leading to the decrease of visible satellites,and the satellite positioning cannot meet the requirements of availability and continuity.The regional navigation system is a ground-based auxiliary positioning system similar to the satellite positioning system,which can assist the satellite positioning system to improve the positioning accuracy and continuity when the satellite signal is blocked.Therefore,in order to further improve the positioning accuracy and convergence speed of PPP,the ambiguity fixing method of precision point positioning is studied.A method of regional navigation system assisting precise point positioning has been studied to effectively solve the problem of positioning availability and continuity in the environment where the satellite signal is blocked.The main work includes:(1)The basic process of PPP and analyzes the main error sources and correction models of PPP are summarized in this thesis.On the basis of the single-differenced ionosphere-free PPP model,an extended Kalman filter algorithm based on ambiguity floating point solution is constructed to realize online estimation of motion state.(2)The reasons for the non-integer characteristic of PPP ambiguity is analyzed,also cascaded ambiguity fixing method is studied in this thesis.Firstly fixing the ambiguity of wide lane,then fixing the ambiguity of narrow lane,and finally fixing the single-differenced ionosphere-free ambiguity.The positioning performance of PPP with fixed ambiguity is verified and analyzed.(3)The carrier phase positioning method of the regional navigation system is studied in this thesis.Based on the single-differenced carrier phase observation,a combined positioning method of the regional navigation system/PPP is designed,and the positioning performance of the tight combination system under different number of available satellites is verified and analyzed.(4)The integrated positioning software of satellite/regional navigation system based on C# language is designed and developed,and its functional requirements and interface requirements are analyzed in this thesis.Then verifies three positioning algorithms: PPP,ambiguity fixing of PPP and tight integrated positioning of regional navigation system/PPP by using experimental data.The experimental results show that comparing with the floating solution,the convergence time of PPP fixed solution with cascaded ambiguity fixing method is reduced from 800 s to 750 s,the north error RMS is reduced from 0.053 m to 0.019 m,and the east error RMS is reduced from 0.09 m to 0.063 m.In the case that the number of available satellites does not meet the positioning conditions,the horizontal error of the regional navigation system/PPP tight combination positioning method is within 30 cm,which can ensure the availability of positioning in the signal blocking environment.This thesis contains 51 figures,9 tables,and 63 references.更多还原