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Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2,3,4,HU XiaoGong2,4,LIU Li1,WU XiaoLi1,HUANG Yong2,4 & HE Feng1 1 Beijing Global Information Application and Development Center,Beijing 100094,china 2 shanghai Astronomical Observatory,Chinese Academy of Sciences,shanghai 200030,china 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 4 space navigation and positioning technology,laboratory of shanghai municipal,shanghai 200030,china Beijing Global Information Application and Development Center Beijing China Chinese Academy of Sciences Shanghai Astronomical Observatory Shanghai China (GRID:grid.9227.e) (ISNI:***) Graduate University of Chinese Academy of Sciences Beijing China (GRID:grid.458514.9) laboratory of shanghai municipal Space Navigation and Positioning Technology Shanghai China (GRID:grid.458514.9) Chinese Academy of Sciences Shanghai Astronomical Observatory Shanghai China (GRID:grid.9227.e) (ISNI:***) laboratory of shanghai municipal Space Navigation and Positioning Technology Shanghai China (GRID:grid.9227.e) Beijing Global Information Application and Development Center Beijing China (GRID:grid.9227.e)

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a Chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.203 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in Beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2-h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.280 m and the 2-h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

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Simulation on C/A codes and analysis of GPS/pseudolite signals acquisition

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Science china(Technological Sciences) 2009年第5期52卷 1459-1462页

作者： ZHANG Lei shanghai Institute of Technical Physics,Chinese Academy of Sciences,shanghai 200083,china shanghai Institute of Technical Physics Chinese Academy of Sciences

The global positioning system(GPS) is an extremely mature technique in the navigation and position-ing ***,there are still some limits in some aspects and for some special ***-cially,the performance of GPS needs to be improved with technological *** a GPS-like ground transmitter,the pseudolite provides a new research direction to achieve high positioning ac-curacy and *** this paper,we describe the core technologies of designing and simulation on the coarse acquisition codes in constructing the pseudolite *** the GPS/pseudolite integration system,the signal PRN 36 of the pseudolite and the GPS satellites signals are acquired in the modified receiver based on the computer software *** is shown that the pseudolite technology is ideally suited to augment the GPS alone and provide greater integrity,availability,and continuity of the navi-gation positioning system,especially for indoor use.

关键词： GPS pseudolite coarse acquisition(C/A) code acquisition

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Polynomial regression calculation of the Earth's position based on millisecond pulsar timing

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Research in Astronomy and Astrophysics 2012年第2期12卷 219-234页

作者： Feng Tian 1,2,Zheng-Hong Tang 1,Qing-Zeng Yan 1,2 and Yong Yu 11 shanghai Astronomical Observatory,Chinese Academy of Sciences,shanghai 200030,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china shanghai Astronomical Observatory Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar timing observations. We can simulate time-of-arrival ground observation data close to actual observed values before using pulsar timing observation data. Considering the correlation between the Earth＇s position and its short arc section of an orbit, we use polynomial regression to build the correlation. Regression coefficients can be calculated using the least square method, and a coordinate component series can also be obtained; that is, we can calcu- late Earth＇s position in the Barycentric Celestial Reference System according to pulse arrival time data and a precise pulsar rotation model. In order to set appropriate param- eters before the actual timing observations for Earth positioning, we can calculate the influence of the spatial distribution of pulsars on errors in the positioning result and the influence of error source variation on positioning by simulation. It is significant that the threshold values of the observation and systematic errors can be established before an actual observation occurs; namely, we can determine the observation mode with small errors and reject the observed data with big errors, thus improving the positioning result.

关键词： autonomous positioning - millisecond pulsar - pulsar timing - re-gression analysis

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An improved approach to the efficient construction of and search operations in motion graphs

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Science china(Information Sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,CHEN ZhiHua 2,CHEN MinGang 3 & SHEN Yang 3 1 Software Engineering Institute,East china Normal University,shanghai 200062,china 2 Department of Computer Science and Engineering,East china University of Science and technology,shanghai 200237,china 3 Department of Computer Science and Engineering,shanghai Jiao Tong University,shanghai 200240,china Software Engineering Institute East China Normal University Shanghai China Department of Computer Science and Engineering East China University of Science and Technology Shanghai China Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

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A New GPS Deformation Monitoring Algorithm Applied to Donghai Bridge

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Journal of shanghai Jiaotong university(Science) 2008年第2期13卷 216-220页

作者：王永泉翟传润张炎华高望 Institute of Aerospace Science & technology Shanghai Jiaotong University shanghai Huace navigation Limited

A real-time,long-round global positioning system (GPS) bridge-deformation monitoring technology was proposed,which processes the carrier phase of multiple GPS receivers in an operation *** was demon- strated an extended Kalman filter with triple differential ionospheric-free measurement (EKF-TIF) which can eliminate the ionospheric delay,whiten the TIF noise and optimize the results of EKF,consequently,achieves a better performance than existing real time kinematic (RTK) *** experiment,which takes an active ionosphere condition into consideration,proves the feasibility of this system by comparing its records to that of a traditional RTK solution,practically,the system installed on the Donghai Bridge has survived a non-break running for five *** analysis to the monitoring records shows the system achieves the designed accu- racy and reliability.

关键词： global positioning system bridge monitoring Kalman filter deformation

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Contemporary crustal movement of continental china obtained by global positioning system(GPS) measurements

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Chinese Science Bulletin 2001年第18期46卷 1552-1554,1588页

We obtain a unified horizontal velocity field of continental china and vicinity through measurements at 81 GPS stations provided by the National Key Infrastructure Project, Crustal Movement Observation Network of china. The velocity field delineates patterns of movements and deformation of active crustal blocks in continental china under the Eurasia-fixed reference frame. The space-based geodesy also clearly shows for the first time the horizontal movementand deformation of continental china induced by indentation of the Indian plate. The data provide kinematic constraints for simulating dynamic process of continental litho-spheric deformation.

关键词： crustal movement velocity field tectonic deformation.

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移动机器人的自学习导航策略

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上海交通大学学报 2001年第5期35卷 779-782,786页

作者：李强林良明颜国正上海交通大学电子信息学院上海200030

针对标准 Q学习收敛较慢的缺点 ,采用多步 Q学习算法 ;为解决连续过程的学习问题 ,采用 CMAC神经网络对连续状态空间进行泛化 .讨论了基于 CMAC的多步 Q学习算法应用于导航系统的实现方法 ,并与其他方法进行仿真比较 ,结果表明了该算法... 详细信息

针对标准 Q学习收敛较慢的缺点 ,采用多步 Q学习算法 ;为解决连续过程的学习问题 ,采用 CMAC神经网络对连续状态空间进行泛化 .讨论了基于 CMAC的多步 Q学习算法应用于导航系统的实现方法 ,并与其他方法进行仿真比较 ,结果表明了该算法的有效性 .

关键词：导航 Q学习 CMAC神经网络移动机器人

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基于平方根卡尔曼滤波的微弱GPS信号跟踪方法

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上海交通大学学报 2009年第7期43卷 1149-1154页

作者：周广宇茅旭初上海交通大学电子信息与电气工程学院上海200240

针对全球定位系统(GPS)的微弱信号跟踪容易失锁问题,提出一种新的跟踪方法.利用平方根卡尔曼滤波算法,在运算过程中运用误差协方差矩阵的平方根形式进行迭代,有效减小了舍入误差带来的影响.提出了一种新的GPS信号跟踪测量模型,在连续积... 详细信息

针对全球定位系统(GPS)的微弱信号跟踪容易失锁问题,提出一种新的跟踪方法.利用平方根卡尔曼滤波算法,在运算过程中运用误差协方差矩阵的平方根形式进行迭代,有效减小了舍入误差带来的影响.提出了一种新的GPS信号跟踪测量模型,在连续积分的基础上,加入了非连续积分过程,通过有效处理,避免了导航信息位翻转对信号相关运算产生的影响.仿真结果表明,新方法可跟踪载噪比低至17 dB-Hz的微弱GPS信号.

关键词：全球定位系统平方根卡尔曼滤波微弱信号处理跟踪

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快速整周模糊度求解技术在高精度GPS定位和导航中的应用

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上海交通大学学报 2004年第12期38卷 2112-2116页

作者：刘维亭王玫张炎华华东船舶工业学院镇江212003 上海交通大学电子信息工程学院上海200030

通过分析搜索空间中的独立变量,推导出新的传递矩阵,该矩阵将所有的测量残差直接和最小求解搜索空间相关联.该技术不仅可以改善计算效率以及缩短模糊度求解时间,还能提高可靠性.通过仅选择那些与卫星几何尺寸和测量残差一致的模糊度的组... 详细信息

通过分析搜索空间中的独立变量,推导出新的传递矩阵,该矩阵将所有的测量残差直接和最小求解搜索空间相关联.该技术不仅可以改善计算效率以及缩短模糊度求解时间,还能提高可靠性.通过仅选择那些与卫星几何尺寸和测量残差一致的模糊度的组合,搜索空间被最小化.实验数据表明了该方法的有效性.

关键词：周模糊度求解残差传递矩阵模糊度搜索空间全球定位系统导航

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New Media technology Application on Public Relations Teaching

New Media Technology Application on Public Relations Teachin...

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第三届教学管理与课程建设学术会议

作者： Hongyan LI Humanities College, shanghai Second Polytechnic University, shanghai, china

New media technologies have put deep impact on public relations education. Methods and contents of teaching communication have taken place creative revolution. Application of new media technologies in public relations teaching communication is gradually popular and expansive. On one hand, changes from curricular to extracurricular, from teacher to student, from time to space bring convenient and modernization to public relations teaching. On the other hand, all aspects of teaching communication are facing some new *** of public relations should be self-positioning, learn and harness new media technologies to enhance their attainment and teaching effectiveness.

关键词： New Media technology Public Relations Teaching Communication Application

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