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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 2.0030,china 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 4.space navigation and positioning technology,laboratory of Shanghai municipal,Shanghai 2.0030,china Beijing Global Information Application and Development Center Beijing China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of Chinese Academy of Sciences Beijing China space navigation and {2. technology Laboratory of Shanghai Municipal Shanghai China

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 0.2.3 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 0.2.0 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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On three-dimensional geological modeling and visualization

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Science china Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. Department of Resource Exploitation Engineering, china University of Mining and technology, Beijing 100083, china 2. Beijing Institute of Petrochemical technology, Beijing 102.17, china Department of Resource Exploitation Engineering China University of Mining and Technology Beijing China Beijing Institute of Petrochemical technology Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

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A study on volunteer augmentation navigation technology

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Science china(Physics,Mechanics & Astronomy) 2011年第6期54卷 1029-1034页

作者： WU HaiTao 1,2.LU XiaoChun 1,2.ZOU DeCai 1,2.& HAN Tao 1,2.1 National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,china 2.Key laboratory of Precision {2. and Timing technology,Chinese Academy of Sciences,Xi’an 710600,china National Time Service Center Chinese Academy of Sciences Xi’an China Key laboratory of Precision navigation and Timing {2. Chinese Academy of Sciences Xi’an China

navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation *** concept of volunteer augmentation navigation (VNA) is proposed and the elements and topological structure of VNA are also analyzed in this *** study focuses on the neural network model that volunteers and ordinary users use modern communication information network to exchange self-organizing *** neural cell model of Volunteer Augmentation navigation using shared information is *** interactive general relative positioning is *** basic theories and methods of volunteer augmentation navigation are formed on the basis of the above-mentioned *** study of realization mechanism of volunteer augmentation technology helps to form a relatively integral architecture of volunteer augmentation navigation.A user self-service satellite navigation augmentation which combines information exchange and navigation services may strengthen the continuity,reliability and integrity of the navigation *** volunteer augmentation navigation theory proposed in this paper improves the traditional satellite navigation application model and expands the connotation and denotation of satellite navigation augmentation methods.

关键词： volunteer augmentation navigation self-organizing information exchange interactive general relative positioning

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A virtual reference satellite differential method for relative correction of satellite ephemeris errors

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2300-2306页

作者： CAI ChengLin 1,3 , LI XiaoHui 2.3 & WU HaiTao 2.3 1 Gulin University of Electronic technology, 541004, china 2.National Time Service Center, Chinese Academy of Sciences, Lintong 710600, china 3 Key laboratory of Precision navigation and Timing technology, National Time Service Center, Chinese Academy of Sciences, Lintong 710600, china Gulin University of Electronic technology Gulin China Key laboratory of Precision navigation and Timing {2. National Time Service Center Chinese Academy of Sciences Lintong China National Time Service Center Chinese Academy of Sciences Lintong China

In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite’s clock and ephemeris errors on positioning can basically be removed and the users’ positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite {2. systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

关键词： wide area differential method virtual reference satellite (VRS) satellite ephemeris errors satellite clock errors constellation

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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2. WU Li-xin1, 2. LI Hui-ying3 1. College of Resources and Civil Engineering, Northeastern University, Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal University, Beijing 100875, china 3. College of Computer Science and {2., Jilin University, Changchun 130012. china College of Resources and Civil Engineering Northeastern University Shenyang 110004 China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China College of Computer Science and technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and {2. of equipments in the mine underground without satellite {2. signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

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Analysis on the positioning precision of CAPS

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Science china(Physics,Mechanics & Astronomy) 2009年第3期52卷 328-332页

作者： JI YuanFa1,2.& SUN XiYan1,2.1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012. china 2.Applied Science and technology College, Guilin University of Electronic technology, Guilin 541004, china National Astronomical Observatories Chinese Academy of Sciences Beijing China Applied Science and technology College Guilin University of Electronic Technology Guilin China

As a newly developed satellite positioning system, the Chinese Area positioning System (CAPS) is a typical direct sequence spread spectrum ranging system like GPS. The positioning precision of such navigation signals depends on many factors, including the pseudo-code rate, the signal to noise ratio, the processing methods for tracking loops and so on. This paper describes the CAPS link budget, the solution approach for CAPS positioning, focusing on the autocorrelation function feature of C/A code signals. The CAPS signal measurement precision is studied by the software approach together with theoretical analysis of the range resolution. Because the conventional Delay Lock Loop (DLL) is vul- nerable to the impact of noise, a narrow correlator and multiple correlators as well as the corresponding discrimination methods of phases are proposed, which improves the robustness of DLL and the code-phase resolution of the measurement. The results show that the improvement of the DLL structure and the discrimination method are the most important way to improve the ranging resolution. Theoretical analysis and experimental results show that a CAPS receiver could reach a 2.-m positioning precision by using three satellites with a supported height from an altimeter.

关键词： satellite navigation receiver narrow correlation tracking loop

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Panel positioning error and support mechanism for a 30-m THz radio telescope

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Research in Astronomy and Astrophysics 2011年第6期11卷 725-736页

作者： De-Hua Yang Daniel Okoh Guo-Hua Zhou Ai-Hua Li Guo-Ping Jing-Quan Cheng National Astronomical Observatories /Nanjing Institute of Astronomical Optics ＆ technology Chinese Academy of SciencesNanjing 210042China Key laboratory of Astronomical Optics ＆ technology Nanjing Institute of Astronomical Optics ＆ TechnologyChinese Academy of SciencesNanjing 210042China Centre for Basic space Science National Space Research and Development AgencyUniversity of NigeriaNsukka 410002Nigeria National Radio Astronomy Observatory CharlottesvilleVA 22903USA

A 30-m TeraHertz（THz） radio telescope is proposed to operate at 2.0 μm with an active primary *** paper presents sensitivity analysis of active surface panel positioning errors with optical performance in terms of the Strehl *** on Ruze＇s surface error theory and using a Monte Carlo simulation,the effects of six rigid panel positioning errors,such as piston,tip,tilt,radial,azimuthal and twist displacements,were directly *** optical performance of the telescope was then evaluated using the standard Strehl *** graphically illustrated the various panel error effects by presenting simulations of complete ensembles of full reflector surface errors for the six different rigid panel positioning *** of the panel error sensitivity analysis revealed that the piston error and tilt/tip errors are dominant while the other rigid errors are much less ***,as indicated by the results,we conceived of an alternative Master-Slave Concept-based（MSC-based） active surface by implementating a special Series-Parallel Concept-based（SPC-based） hexapod as the active panel support mechanism.A new 30-m active reflector based on the two concepts was demonstrated to achieve correction for all the six rigid panel positioning errors in an economically feasible way.

关键词： telescopes-methods:data analysis-methods:statistical-techniques:miscellaneous

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Power minimization with derivative constraints for high dynamic GPS interference suppression

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Science china(Information Sciences) 2012年第4期55卷 857-866页

作者： WU RenBiao 1,2.LI Chan 1 & LU Dan 1 1 Tianjin Key laboratory for Advanced Signal Processing,Civil Aviation University of china,Tianjin 300300,china 2.Intelligent Information Institute of ATR Lab,Shenzhen University,Shenzhen,518060,china Tianjin Key laboratory for Advanced Signal Processing Civil Aviation University of China Tianjin China Intelligent Information Institute of ATR Lab Shenzhen University Shenzhen China

In this paper,a novel adaptive interference suppression algorithm is proposed for high dynamic GPS (global positioning system) *** new method incorporates derivative constraints on the inter-ference DOA (direction of arrival) into power minimization approach,which could broaden the width of nulls in the interferences directions and adapt to the rapid change of the interference *** with the traditional wide nulling algorithm based on the derivative constraints,the new method does not have to know or estimate the DOAs of the desired signal and the *** new method is firstly discussed in the context of spatial processing,and then extended to space-time adaptive processing to mitigate wideband diffusive multipath *** of the new method is verified via simulation examples.

关键词： GPS interference cancellation adaptive arrays space-time adaptive processing high dynamic GPS receiver

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A new method of ionospheric-free hybrid differential positioning based on a double-antenna CAPS receiver

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Science china(Physics,Mechanics & Astronomy) 2009年第3期52卷 368-375页

作者： GUO JinYun1,2. HAN YanBen1 & CHANG XiaoTao3 1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012. china 2.College of Geodesy and Geomatics, Shandong University of Science and technology, Qingdao 2.6510, china 3 Chinese Academy of Surveying and Mapping, Beijing 100039, china National Astronomical Observatories Chinese Academy of Sciences Beijing China College of Geodesy and Geomatics Shandong University of Science and Technology Qingdao China Chinese Academy of Surveying and Mapping Beijing China

Chinese Area positioning System (CAPS) is a transmitted satellite navigation system moved by the Chinese Academy of Sciences. Three basic modes of navigation and positioning with CAPS are given, and then a comparative analysis is made in this paper. In terms of the principle that the ionospheric delay is at an inverse ratio to the frequency square, a new ionospheric-free positioning method based on a double-antenna CAPS receiver is put forward. Then the hybrid differential observations and the solving equations and algorithms for one epoch and multi epochs are deduced according to the basic principle of the method. The method may remove the global errors in signal emission, propagation, transmission and receiving (e.g., ionospheric delay, hardware delay, and clock error). So it is very convenient for the single-epoch solution and multi-epoch navigation and positioning, and may efficiently improve the precision of real time CAPS navigation. Furthermore, the method can be used not only for the geometric orbit determination of CAPS GEO and IGSO satellites and the navigation and positioning, but also for the estimation of the tropospheric zenith delay, which is useful for the study of water vapor changes in the atmosphere. Polynomials are used in this method to express the tropospheric zenith delay and CAPS satellite orbits within the limited time interval, which reduces the num- ber of unknown parameters and thus speeds the computation.

关键词： Chinese Area positioning System (CAPS) ionospheric-free linear combination double-antenna receiver hybrid differential positioning method

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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 2.0030,china 2.Graduate University of Chinese Academy of Sciences,Beijing 100049,china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

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 {2., we can calculate the influence of the spatial distribution of pulsars on errors in the {2. result and the influence of error source variation on {2. 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 {2. result.

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

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