GNSS性能增强技术研究

发布时间：2018-04-17 18:41

本文选题：全球卫星导航系统 + 可用性　；参考：《上海交通大学》2013年博士论文

【摘要】：在全球导航卫星系统(GNSS)得到广泛应用的今天，国民经济各领域对卫星导航的依赖程度逐渐增大，与此同时卫星导航的一些不足之处也日渐受到关注。在可用性、完好性、定位精度和连续性这四大指标中除连续性参数能够满足需要外，其他三者都存在不足。可用性的不足体现在因星座几何布局、信号遮蔽等因素造成的信号覆盖不足，城市与室内应用受限；完好性的不足体现在尚不能满足涉及生命安全的特定应用领域对完好性的需求；定位精度不足则是指普通用户希望能以低廉的成本获得更高精度的定位服务。如何基于现有的导航系统基础设施与用户设备，改善与提高GNSS综合服务性能，是当前学界的研究热点，也是各导航卫星系统供应商的工作重点。国际卫星导航委员会还专门成立了服务性能提升工作组，专门讨论性能增强相关问题，，致力于寻求解决方案。本文就GNSS性能增强主题，重点针对可用性、完好性和精度三大指标的不足，分别以伪卫星为技术手段，深入研究了伪卫星系统及其组网与定位算法，以改善GNSS信号覆盖的不足，提高可用性；基于星间链路及星间测距技术方案，提出了卫星自主完好性监测与星历增强方法，以提高完好性和精度。论文还提出了一种新型的工作于光学频段、基于到达时间差算法的定位系统理论与方案，以更好得解决室内定位的难题。本文的主要研究工作和方法体现在五个方面：（1）对伪卫星定位系统的理论与应用进行了梳理，对伪卫星应用的兼容、定位解算等问题进行了分析与探讨。（2）研究了伪卫星组网定位算法，提出了独立伪卫星单点定位算法；设计开发了单体伪卫星硬件与组网软件，搭建了一个伪卫星定位的演示验证系统，用于算法验证。（4）研究了GNSS的完好性，提出了基于星间测距的卫星自主完好性监测算法。（5）研究并提出了基于星间测距的卫星自主星历增强算法。（6）分析并对比了基于各类不同物理量、不同原理的定位方法，提出了基于到达时间差的光定位方法，并对其中的相关理论与实现问题进行了探讨。本论文研究的关键技术和创新点主要体现在以下几个方面：（1）提出了独立伪卫星单点定位算法连同所需的初始化方法，并进行了仿真验证。该算法开拓了伪卫星的新应用领域，同时还具有延伸到基于各种机会信号SOOP定位应用的潜力。（2）独立研制了一套包括完整软、硬件的具有自主知识产权的伪卫星定位系统，既能用于构建具有实用价值的室内外定位系统，还能够用以研究与验证各类相关的伪卫星定位技术与算法。（3）提出了基于星间链路的卫星自主完好性监测算法，给出了推导、方法以及性能指标。该算法能够与地面完好性监测、用户自主完好性监测等方法一同提高卫星导航系统的完好性。（4）提出了基于星间链路的卫星自主星历增强算法，给出了推导、方法与仿真结果。该算法能够在不依赖地面监测站的前提下，显著提高卫星星历精度。（5）提出了利用光学频段进行到达时间差方法的室内定位。分析了使用光学频段的优势，并针对其特点探讨了系统方案、所使用的测距码以及接收处理方案等问题。基于上述研究内容，本论文的研究结论包括：（1）伪卫星系统作为GNSS系统的增强与补充，能够发挥很大的作用，在室内、城市等应用场合，提供与GNSS相当甚至更优的定位能力。（2）利用GNSS卫星所拥有的星间测距功能，通过论文所给的自主完好性监测算法，能够在星座间实现自主监测，进一步提高完好性；在进行自主星历增强时，可将用户等效定位误差（URE）由1.05m降至0.34m。（3）基于光频段的室内定位系统具有精度高、无电磁干扰等诸多优点，具有很大的发展空间与应用价值。
[Abstract]:In the global navigation satellite system (GNSS) has been widely used in various fields of the national economy today, reliance on satellite navigation is gradually increased, at the same time some shortcomings of satellite navigation also has attracted much attention. In the availability, integrity, the four indicators of the positioning accuracy and continuity in addition to continuous parameters to meet the needs of foreign and the other three are insufficient. Lack of availability is reflected in the constellation for geometric layout, signal shielding signal caused by insufficient coverage, city and indoor application is limited; lack of integrity is reflected in the still can not meet the specific application to life safety of readiness requirements; positioning accuracy refers to the general lack of users want to get more accurate positioning service with low cost. Based on the existing navigation system infrastructure and user equipment, to improve and enhance the comprehensive GNSS. Service performance is a hot topic in current academic circles. It is also the focal point of every navigation satellite system supplier. The International Navigation Satellite Committee has set up a service performance improvement working group, focusing on performance enhancement related issues, and is committed to finding solutions.
This paper focuses on the theme of enhancing GNSS performance, availability, lack of integrity and accuracy of the three indicators, respectively by pseudo satellite technology, in-depth study of the pseudo satellite system and its networking and positioning algorithm, to improve the GNSS signal coverage, improve the availability; based on the inter satellite link and inter satellite ranging technology plan put forward to enhance the method of Satellite Autonomous Integrity Monitoring and ephemeris, to improve the integrity and accuracy. The paper also puts forward a new type of work in the optical band, the theory and scheme of positioning system based on time difference of arrival algorithm, to solve the problem of better indoor location. The main research work and methods of this paper are reflected in the five aspects:
(1) the theory and application of the pseudo satellite positioning system are combed, the compatibility of the pseudo satellite application and the location solution are analyzed and discussed.
(2) the algorithm of pseudorandom network localization is studied, and the algorithm of single point positioning is put forward. The hardware and Networking software of the single satellite are designed and developed, and a demonstration and verification system of pseudo satellite positioning is set up for algorithm validation.
(4) the integrity of GNSS is studied, and a satellite autonomous integrity monitoring algorithm based on inter satellite distance measurement is proposed.
(5) a satellite ephemeris enhancement algorithm based on INTERSTAR distance measurement is proposed and proposed.
(6) we analyzed and compared the localization methods based on all kinds of physical quantities and different principles. We proposed the optical location method based on the time difference of arrival, and discussed the related theories and implementation problems.
The key technologies and innovation points in this paper are mainly reflected in the following aspects:
(1) a single point positioning algorithm with independent pseudorandom is proposed, together with the required initialization method, and verified by simulation. The algorithm opens up the new application area of pseudorandom, and also extends to the potential application of SOOP location based on all kinds of chance signals.
(2) independently developed a complete set of hardware and software independent intellectual property rights of the pseudo-satellite positioning system, which can be used to build practical indoor and outdoor positioning system, but also can be used to research and verify all kinds of related pseudo satellite positioning technology and algorithm.
(3) a satellite autonomous integrity monitoring algorithm based on inter satellite links is proposed. The derivation, method and performance index are given. The algorithm can improve the integrity of the satellite navigation system with the methods of integrity monitoring and user integrity monitoring.
(4) a satellite based autonomous ephemeris enhancement algorithm based on inter satellite links is proposed. The derivation, method and simulation results are given. The algorithm can significantly improve the accuracy of satellite ephemeris without relying on ground monitoring stations.
(5) put forward the indoor location method using optical frequency band to reach the time difference of arrival. The advantage of using optical frequency band is analyzed, and the system plan, the ranging code and the receiving and processing plan are discussed according to its characteristics.
Based on the above research content, the conclusions of this paper include:
(1) the pseudorandom system can play a great role in enhancing and supplementation of GNSS system. It can provide a comparable or even better location capability in GNSS and indoor applications.
(2) using the GNSS satellite have inter satellite ranging function, through the autonomous integrity monitoring algorithm, can realize the independent monitoring in the constellation, to further improve the readiness; in their ephemeris can be enhanced when the user equivalent positioning error (URE) from 1.05M to 0.34m.
(3) the indoor positioning system based on optical frequency band has many advantages, such as high precision, no electromagnetic interference and so on. It has great development space and application value.

【学位授予单位】：上海交通大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TN96.1

【参考文献】