北斗系统集中式自主实时轨道确定与时间同步方法研究
发布时间：2018-08-25 20:24
【摘要】：是否具有独立自主研发的卫星导航系统是衡量一个国家经济、军事及政治实力的重要标志之一。正因为如此,美国、俄罗斯已先后建成GPS及GLONASS系统,欧盟也开始了Galileo系统的建设工作。为了保障国家安全,我国也于1994年开始着手建设和发展北斗卫星导航系统(简称BDS)。至今,我国已发射了16颗北斗导航卫星,具备了由5个GEO、5个IGSO及4个MEO卫星组成的区域无源服务能力,预计到2020年左右将具备由5个GEO和30个非静止卫星组成的全球无源服务能力。 由地面控制系统(Operational Control Segment-OCS)提供并经由卫星播发给用户的卫星星历是导航定位不可或缺的重要资料,其精度决定了卫星导航系统的服务性能。因此,卫星导航系统能否正常运行很大程度上取决于OCS,若OCS出现故障抑或主控站在战时被敌方摧毁,整个卫星导航系统将很快陷入瘫痪。就算在正常运行情况下,系统的导航定位服务性能也将在很大程度上取决于地面监测站的数量及地理分布。但由于受政治、外交和国土面积等因素的影响,我国无法像美国一样全球大量布站,因此,建立星间链路、减小卫星导航系统对地面站的依赖是北斗卫星导航系统实现全球无源服务能力的关键。 星间链路的建立意味着卫星导航系统对OCS的依赖得到了解放、其在战时或重大自然灾害情况下的生存能力得到了提高、地面监测站布设对系统性能的影响得到了降低。早在20世纪80年代,GPS卫星导航系统就已开展了自主定轨的相关技术研究,但由于导航系统自主定轨技术的敏感性及保密性,国外公开的相关资料不仅数量少,而且很少涉及核心算法及关键技术。不仅如此,北斗卫星导航系统的星座构型及地面站布局等方面均有别于GPS系统,也不可能完全照搬国外的理论与技术。因此,要建成一个我国独立自主的全球卫星导航系统,保证其运行服务性能及战时生存能力,开展基于北斗卫星导航系统的自主定轨技术研究显得尤为重要。 本文以北斗系统仿真星座为对象,对集中式自主实时轨道确定与时间同步的模型及算法进行了系统性的研究,并自主研制了一套仿真分析软件。本文利用该软件进行了大量算例分析,验证了此软件的正确性及可靠性,并得出了一些有益结论,为北斗系统的自主导航建设提供了参考。详细来看,本文所做工作及主要贡献可归纳如下： 1、提出了一种适用于实时滤波轨道解算的小步长低阶Collocation积分方法,并以二体问题及GPS卫星为对象,对其积分性能进行了详细分析。结果表明：在一定长度的积分步长范围内,将小步长低阶Collocation方法用于逐历元滤波轨道解算是可行且有效的； 2、详细推导了星间／星地双向组合观测方程及星间／星地单向观测方程的组成形式,并从理论上对比分析了双向及单向观测方程的优劣；在此基础上,深入研究了参数分解滤波模型与参数整体滤波模型的构成形式,分别从解算结果精度、解算耗时及卫星状态与钟差参数相关性这三个方面分析了两者的性能；最后,综合参数分解与参数整体滤波模型的形式提出了一种适用于单向锚固站观测值情况下的参数半分解滤波模型算法,利用其进行20天定轨解算,结果证明了该模型的正确性及有效性； 3、采用赫尔默特方差分量估计实现了星间及星地两类观测值的融合。在给出其详细计算过程的前提下,通过仿真计算证明了本文所采用的基于方差分量估计的滤波解算过程是正确且有效的； 4、通过仿真验算分析了星间链路的加入对GEO卫星定轨精度的影响,结果表明：考虑了星间链路之后,GEO卫星轨道确定结果精度有了较大的改善,其改善量级达到dm级，，其结果系统变化特性得到了一定的消除且其结果的收敛效果及速度都得到了明显的改进和提高； 5、提出采用短弧定轨法进行集中式自主实时轨道确定与时间同步过程中GEO卫星机动轨道的快速恢复。结果显示：采用本文提出的解算流程不仅可以在较短时间内恢复机动星的轨道精度,而且还能保证机动星自主轨道确定的连续性； 6、在项目组既有软件平台基础上,研制了一套北斗系统集中式自主实时轨道确定与时间同步的仿真分析软件。该软件可用于星间／星地伪距观测值仿真、集中式自主实时轨道确定与时间同步、GEO卫星机动轨道快速恢复及结果精度评定等。本文利用该软件进行了大量的验算分析工作,证明了软件的正确性及可靠性,并得出了一系列有益结论。
[Abstract]:Whether the satellite navigation system is independently developed or not is one of the important symbols to measure a country's economic, military and political strength. For this reason, the United States, Russia has successively built GPS and GLONASS systems, and the European Union has begun the construction of Galileo system. So far, China has launched 16 Beidou navigation satellites with the regional passive service capability of 5 GEO, 5 IGSO and 4 MEO satellites. It is expected that by 2020, China will have a global passive service capability of 5 GEO and 30 non-geostationary satellites.
Satellite ephemeris provided by Operational Control Segment-OCS and transmitted to users via satellite is an indispensable and important data for navigation and positioning. Its accuracy determines the service performance of the satellite navigation system. Therefore, the normal operation of the satellite navigation system depends largely on the OCS, if the OCS fails or the main one occurs. Even under normal operating conditions, the performance of the navigation and positioning services of the system will depend to a great extent on the number and geographical distribution of ground monitoring stations. However, due to political, diplomatic and territorial factors, China can not be like the United States. As a result, the establishment of inter-satellite links and the reduction of the dependence of the satellite navigation system on ground stations are the key to the realization of the global passive service capability of the Beidou satellite navigation system.
The establishment of inter-satellite links means that the satellite navigation system relies on OCS, its survivability is improved in wartime or in serious natural disasters, and the impact of ground monitoring stations on the performance of the system is reduced. As early as the 1980s, the GPS satellite navigation system has carried out independent orbit determination related technologies. However, due to the sensitivity and confidentiality of the autonomous orbit determination technology of the navigation system, the amount of relevant information published abroad is not only small, but also seldom involves the core algorithm and key technology. Therefore, it is very important to study the autonomous orbit determination technology based on Beidou Satellite Navigation System in order to build an independent global satellite navigation system to ensure its operational performance and wartime survivability.
Taking the Beidou system simulation constellation as the object, this paper systematically studies the model and algorithm of centralized autonomous real-time orbit determination and time synchronization, and develops a set of simulation analysis software independently. A large number of examples are analyzed by using this software to verify the correctness and reliability of the software, and some useful results are obtained. The main contributions of this paper can be summarized as follows:1.
1. A small-step low-order Collocation integration method for real-time filtering trajectory calculation is proposed, and the integration performance of the two-body problem and GPS satellites is analyzed in detail. The results show that the small-step low-order Collocation method is applied to epoch-by-epoch filtering trajectory calculation in a certain range of integration steps. Feasible and effective;
2. The two-way combined observational equation between satellites and earth and the one-way observational equation between satellites and earth are deduced in detail, and the advantages and disadvantages of the two-way and one-way observational equation are analyzed theoretically. Finally, a parameter semi-decomposition filtering model algorithm for unidirectional anchorage station observation is proposed in the form of parameter decomposition and parameter global filtering model, which can be used for 20 days orbit determination. The correctness and effectiveness of the model are verified.
3. Helmert variance component estimation is used to realize the fusion of inter-satellite and inter-satellite and ground observations.
4. The influence of inter-satellite links on the orbit determination accuracy of GEO satellite is analyzed by simulation. The results show that the orbit determination accuracy of GEO satellite is greatly improved after inter-satellite links are considered, and the order of improvement is dm. The variation characteristics of the system are eliminated to a certain extent, and the convergence effect and speed of the result are both eliminated. Obvious improvement and improvement have been achieved.
5. A short-arc orbit determination method is proposed to recover the maneuvering orbit of GEO satellite in the process of centralized autonomous real-time orbit determination and time synchronization.
6. Based on the existing software platform of the project team, a set of simulation and analysis software for the centralized autonomous real-time orbit determination and time synchronization of Beidou system is developed. The software can be used for the simulation of inter-satellite/ground pseudo-range observations, the centralized autonomous real-time orbit determination and time synchronization, the quick recovery of GEO satellite maneuvering orbit and the accuracy evaluation of the results. In this paper, a lot of checking and analysis work has been done with the software, which proves the correctness and reliability of the software, and a series of useful conclusions have been drawn.
【学位授予单位】：武汉大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：P228.4
本文编号：2204001
[Abstract]:Whether the satellite navigation system is independently developed or not is one of the important symbols to measure a country's economic, military and political strength. For this reason, the United States, Russia has successively built GPS and GLONASS systems, and the European Union has begun the construction of Galileo system. So far, China has launched 16 Beidou navigation satellites with the regional passive service capability of 5 GEO, 5 IGSO and 4 MEO satellites. It is expected that by 2020, China will have a global passive service capability of 5 GEO and 30 non-geostationary satellites.
Satellite ephemeris provided by Operational Control Segment-OCS and transmitted to users via satellite is an indispensable and important data for navigation and positioning. Its accuracy determines the service performance of the satellite navigation system. Therefore, the normal operation of the satellite navigation system depends largely on the OCS, if the OCS fails or the main one occurs. Even under normal operating conditions, the performance of the navigation and positioning services of the system will depend to a great extent on the number and geographical distribution of ground monitoring stations. However, due to political, diplomatic and territorial factors, China can not be like the United States. As a result, the establishment of inter-satellite links and the reduction of the dependence of the satellite navigation system on ground stations are the key to the realization of the global passive service capability of the Beidou satellite navigation system.
The establishment of inter-satellite links means that the satellite navigation system relies on OCS, its survivability is improved in wartime or in serious natural disasters, and the impact of ground monitoring stations on the performance of the system is reduced. As early as the 1980s, the GPS satellite navigation system has carried out independent orbit determination related technologies. However, due to the sensitivity and confidentiality of the autonomous orbit determination technology of the navigation system, the amount of relevant information published abroad is not only small, but also seldom involves the core algorithm and key technology. Therefore, it is very important to study the autonomous orbit determination technology based on Beidou Satellite Navigation System in order to build an independent global satellite navigation system to ensure its operational performance and wartime survivability.
Taking the Beidou system simulation constellation as the object, this paper systematically studies the model and algorithm of centralized autonomous real-time orbit determination and time synchronization, and develops a set of simulation analysis software independently. A large number of examples are analyzed by using this software to verify the correctness and reliability of the software, and some useful results are obtained. The main contributions of this paper can be summarized as follows:1.
1. A small-step low-order Collocation integration method for real-time filtering trajectory calculation is proposed, and the integration performance of the two-body problem and GPS satellites is analyzed in detail. The results show that the small-step low-order Collocation method is applied to epoch-by-epoch filtering trajectory calculation in a certain range of integration steps. Feasible and effective;
2. The two-way combined observational equation between satellites and earth and the one-way observational equation between satellites and earth are deduced in detail, and the advantages and disadvantages of the two-way and one-way observational equation are analyzed theoretically. Finally, a parameter semi-decomposition filtering model algorithm for unidirectional anchorage station observation is proposed in the form of parameter decomposition and parameter global filtering model, which can be used for 20 days orbit determination. The correctness and effectiveness of the model are verified.
3. Helmert variance component estimation is used to realize the fusion of inter-satellite and inter-satellite and ground observations.
4. The influence of inter-satellite links on the orbit determination accuracy of GEO satellite is analyzed by simulation. The results show that the orbit determination accuracy of GEO satellite is greatly improved after inter-satellite links are considered, and the order of improvement is dm. The variation characteristics of the system are eliminated to a certain extent, and the convergence effect and speed of the result are both eliminated. Obvious improvement and improvement have been achieved.
5. A short-arc orbit determination method is proposed to recover the maneuvering orbit of GEO satellite in the process of centralized autonomous real-time orbit determination and time synchronization.
6. Based on the existing software platform of the project team, a set of simulation and analysis software for the centralized autonomous real-time orbit determination and time synchronization of Beidou system is developed. The software can be used for the simulation of inter-satellite/ground pseudo-range observations, the centralized autonomous real-time orbit determination and time synchronization, the quick recovery of GEO satellite maneuvering orbit and the accuracy evaluation of the results. In this paper, a lot of checking and analysis work has been done with the software, which proves the correctness and reliability of the software, and a series of useful conclusions have been drawn.
【学位授予单位】：武汉大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：P228.4
【参考文献】
相关期刊论文 前4条
1 朱俊;文援兰;陈忠贵;廖瑛;;基于抗差UD分解滤波的导航星座整网定轨方法[J];系统工程与电子技术;2010年06期
2 郭睿;胡小工;黄勇;刘利;谭红力;吴晓莉;;导航卫星的短弧运动学定轨[J];飞行器测控学报;2010年01期
3 韩健,刘岩,原洪峰;星载GPS地球静止轨道卫星自主定轨的新算法[J];测绘学院学报;2005年03期
4 刘经南,曾旭平,夏林元,赵齐乐;导航卫星自主定轨的算法研究及模拟结果[J];武汉大学学报(信息科学版);2004年12期
相关博士学位论文 前2条
1 宋小勇;COMPASS导航卫星定轨研究[D];长安大学;2009年
2 曾旭平;导航卫星自主定轨研究及模拟结果[D];武汉大学;2004年
本文编号：2204001
本文链接：https://www.wllwen.com/kejilunwen/dizhicehuilunwen/2204001.html
