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Precise orbit determination for GRACE with zero-difference kinematic method

LI JianCheng,ZHANG ShouJian,ZOU XianCai &,JIANG WeiPing,

科学通报(英文版) , 2010,
Abstract: Thanks to the high performance of the spaceborne GPS receiver and the availability of precise IGS orbit and clock products,zero-difference kinematic precise orbit determination(POD) has been turned out to be a new effective method in orbit determination for the LEO satellites.Zero-difference kinematic POD,which is based on the GPS measurements only from the spaceborne GPS receiver,does not depend on the force models and orbit design.From this point of view,kinematic POD is suitable for the Earth observation...
Precise orbit determination for GRACE with zero-difference kinematic method
JianCheng Li,ShouJian Zhang,XianCai Zou,WeiPing Jiang
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-009-0286-0
Abstract: Thanks to the high performance of the spaceborne GPS receiver and the availability of precise IGS orbit and clock products, zero-difference kinematic precise orbit determination (POD) has been turned out to be a new effective method in orbit determination for the LEO satellites. Zero-difference kinematic POD, which is based on the GPS measurements only from the spaceborne GPS receiver, does not depend on the force models and orbit design. From this point of view, kinematic POD is suitable for the Earth observation satellites at very low altitudes, such as CHAMP, GRACE and GOCE, etc. This paper first reviews the basic zero-difference GPS observation model. Then a modified data quality control scheme is put forward. Finally, a block-wise least squares algorithm, which first separates the parameters into several groups and then solves the parameters by elimination and back-substitution, is discussed and proposed for the kinematic orbit determination. With the above algorithms, we developed kinematic POD software to solve the orbit suitable for one-week GRACE observations. Comparisons with the published Rapid Science Orbit (RSO) indicate that, using our approach to determine the orbit, the accuracy in the radial direction can achieve 3–4 cm for GRACE-A, and 3–5 cm for GRACE-B.
Kinematic and reduced-dynamic precise orbit determination of low earth orbiters
D. vehla,M. Rothacher
Advances in Geosciences (ADGEO) , 2003,
Abstract: Various methods for kinematic and reduced-dynamic precise orbit determination (POD) of Low Earth Orbiters (LEO) were developed based on zero- and double-differencing of GPS carrier-phase measurements with and without ambiguity resolution. In this paper we present the following approaches in LEO precise orbit determination: – zero-difference kinematic POD, – zero-difference dynamic POD, – double-difference kinematic POD with and without ambiguity resolution, – double-difference dynamic POD with and without ambiguity resolution, – combined GPS/SLR reduced-dynamic POD. All developed POD approaches except the combination of GPS/SLR were tested using real CHAMP data (May 20-30, 2001) and independently validated with Satellite Laser Ranging (SLR) data over the same 11 days. With SLR measurements, additional combinations are possible and in that case one can speak of combined kinematic or combined reduced-dynamic POD. First results of such a combined GPS/SLR POD will be presented, too. This paper shows what LEO orbit accuracy may be achieved with GPS using different strategies including zerodifference and double-difference approaches. Kinematic versus dynamic orbit determination is presently an interesting issue that will also be discussed in this article. Key words. POD, kinematic orbit, dynamic orbit, LEO, CHAMP, ambiguity resolution, GPS, SLR
GPS卫星钟差及观测数据采样间隔对LEO卫星定轨精度影响
Impact of Sample Rate of GPS Satellite Clock and Observation Data on LEO GPS-Based Precise Orbit Determination
 [PDF]

田英国, 郝金明, 陈明剑, 于合理, 衡培深
TIAN Yingguo
, HAO Jinming, CHEN Mingjian, YU Heli, HENG Peishen

- , 2017, DOI: 10.13203/j.whugis20150591
Abstract: 针对GPS卫星钟差及观测数据间隔对LEO卫星运动学和约化动力学定轨的影响问题进行了分析,并使用CODE(the Center for Orbit Determination in Europe)30 s、5 s间隔GPS卫星钟差分别进行了30 s和10 s间隔观测数据的LEO卫星定轨实验。结果表明,使用5 s间隔卫星钟差(10 s间隔观测数据)相比30 s间隔卫星钟差(30 s间隔观测数据)进行GRACE卫星精密定轨,约化动力学定轨精度提高了16%,运动学定轨精度提高了8.8%;使用30 s间隔卫星钟差和10 s间隔观测数据的定轨精度最低;对于30 s间隔观测数据,使用30 s或5 s间隔卫星钟差的定轨精度基本一致
PROGRESS AND MATHEMATIC MODELS OF ON-BOARD GPS PRECISE ORBIT DETERMINATION
星载GPS精密定轨进展及其数学模型

Zheng Zuoya,Huang Cheng,Lu Xiushan,
郑作亚
,黄珹,卢秀山

大地测量与地球动力学 , 2007,
Abstract: On the basis of the theory of on-board GPS precise orbit determination (POD), having analyzed and discussed functional model and stochastic model of on-board GPS low earth orbit (LEO) satellite, the linear combination, zero-differential and differential functional model form and their advantages and disadvantages are put forward. According to different ideas and models for solution,some methods for orbit determinations: one-step POD, two-step POD, dynamic POD, reduced-dynamic POD, geometry POD and kinematic POD are analyzed. Finally, the on-board GPS geometry-dynamic POD method and its prospective are discussed.
ZERO-DIFFERENCE KINEMATIC PRECISE ORBIT DETERMINATION OF LOW EARTH ORBIT SATELLITE
低轨卫星的非差运动学精密定轨

Wang Wei,Wang Haihong,Luo Jia,Zhong Bo,
王伟
,汪海洪,罗佳,钟波

大地测量与地球动力学 , 2009,
Abstract: The approaches to precise orbit determination(POD) for satellites in Low Earth Orbit(LEO) were sumed up,and the theory,the steps and the factor influencing the accuracy of zero-difference kinematic POD were analyzed.Futhermore,by comparing the zero-difference kinematic orbit determination with double-difference kinematic,zero-difference reduced-dynamic and double-difference reduced-dynamic orbit determination it is found that with this method not only the accuracy close to that with other three methods can ...
Precise orbit determination for Jason-1 satellite using on-board GPS data with cm-level accuracy
DongJu Peng,Bin Wu
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-008-0513-0
Abstract: The joint US/French Jason-1 satellite altimeter mission, launched from the Vandenberg Air Force Base on December 7, 2001, continues the time series of centimeter-level ocean topography observations as the follow-on to the highly successful T/P radar altimeter satellite. Orbit error especially the radial orbit error is a major component in the overall budget of all altimeter satellite missions, in order to continue the T/P standard of observations. Jason-1 has a radial orbit error budget requirement of 2.5 cm. In this work, two cycles (December 19, 2002 to January 7, 2003) of the Jason-1 on-board GPS data were processed using the zero-difference (ZD) dynamic precise orbit determination (POD) technique. The resulting Jason-1 orbit accuracy was assessed by comparison with the precise orbit ephemeris (POE) produced by JPL, orbit overlaps and SLR residuals. These evaluations indicate that the RMS radial accuracy is in the range of 1–2 cm.
Precise orbit determination for Jason-1 satellite using on-board GPS data with cm-level accuracy

PENG DongJu &,WU Bin,

科学通报(英文版) , 2009,
Abstract: The joint US/French Jason-1 satellite altimeter mission, launched from the Vandenberg Air Force Base on December 7, 2001, continues the time series of centimeter-level ocean topography observations as the follow-on to the highly successful T/P radar altimeter satellite. Orbit error especially the radial orbit error is a major component in the overall budget of all altimeter satellite missions, in order to continue the T/P standard of observations. Jason-1 has a radial orbit error budget requirement of 2.5 cm. In this work, two cycles (December 19, 2002 to January 7, 2003) of the Jason-1 on-board GPS data were processed using the zero-difference (ZD) dynamic precise orbit determination (POD) technique. The resulting Jason-1 orbit accuracy was assessed by comparison with the precise orbit ephemeris (POE) produced by JPL, orbit overlaps and SLR residuals. These evaluations indicate that the RMS radial accuracy is in the range of 1–2 cm. Supported by the National Natural Science Foundation of China (Grant No. 40274006), High-tech Research and Development Program of China (Grant No. 2006AA12A107) and Science & Technology Commission of Shanghai Municipality (Grant No. 06DZ22101)
Estimation of LEO GPS receiver instrument biases
LEO GPS接收机仪器偏差估计

林剑,吴云,熊晶,祝芙英,杨剑
地球物理学报 , 2010,
Abstract: The GPS LEO measurements have become a powerful tool for special ionospheric studies, and TEC derived from GPS dual frequency measurements is an important parameter in ionospheric detection. The GPS receiver instrument biases (often called differential code biases (DCB)) must be estimated and eliminated from the data in order to obtain precise TEC. The objective of this paper is to grope for a brand-new method of estimation of LEO GPS receiver instrument biases: based on the assumption of spherical symmetry of ionosphere, utilizing raw GPS observation data from CHAMP and COSMIC, applying geometric mapping function, the instrument biases could be calculated by least-square technique. The results show that: (1) during Jan.1~31,2008, the DCB calculated by above method were stable, and compared with the web-published result of COSMIC all the standard deviations were less than 0.6 ns; (2) the estimated DCB of COSMIC (orbit altitude about 800 km) were better than that of CHAMP (orbit altitude about 400 km), the reason is that for estimation of DCB at different LEO orbit altitudes, the effects of spherical symmetry of ionosphere at higher orbit altitude were less.
Improved Between-Satellite Single-Difference Precise Point Positioning Model Using Triple GNSS Constellations: GPS, Galileo, and BeiDou  [PDF]
Akram Afifi, Ahmed El-Rabbany
Positioning (POS) , 2016, DOI: 10.4236/pos.2016.72006
Abstract: This paper introduces a new dual-frequency precise point positioning (PPP) model, which combines the observations of three different GNSS constellations, namely GPS, Galileo, and BeiDou. Our model is based on between-satellite single-difference (BSSD) linear combination, which cancels out some receiver-related biases, including receiver clock error and non-zero initial phase bias of the receiver oscillator. The reference satellite can be selected from any satellite system GPS, Galileo, and BeiDou when forming BSSD linear combinations. Natural Resources Canada’s GPS Pace PPP software is modified to enable a combined GPS, Galileo, and BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets at four IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the IGS-MGEX network are used to correct both of the GPS and Galileo measurements. It is shown that using the BSSD linear combinations improves the precision of the estimated parameters by about 25% compared with the GPS-only PPP solution. Additionally, the solution convergence time is reduced to 10 minutes for both BSSD scenarios, which represent about 50% improvement in comparison with the GPS-only PPP solution.
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