Precise Orbit Determination for Haiyang 2A Satellite Using Un-differenced DORIS Code and Phase Measurements

AbstractZero-difference kinematic, dynamic and reduced-dynamic precise orbit determination (POD) are three methods to obtain the precise orbits of Low Earth Orbit satellites (LEOs) by using the on-board GPS observations. Comparing the differences between those methods have great significance to establish the mathematical model and is usefull for us to select a suitable method to determine the orbit of the satellite. Based on the zero-difference GPS carrier-phase measurements, Shanghai Astronomical Observatory (SHAO) has improved the early version of SHORDE and then developed it as an integrated software system, which can perform the POD of LEOs by using the above three methods. In order to introduce the function of the software, we take the Gravity Recovery And Climate Experiment (GRACE) on-board GPS observations in January 2008 as example, then we compute the corresponding orbits of GRACE by using the SHORDE software. In order to evaluate the accuracy, we compare the orbits with the precise orbits provided by Jet Propulsion Laboratory (JPL). The results show that: (1) If we use the dynamic POD method, and the force models are used to represent the non-conservative forces, the average accuracy of the GRACE orbit is 2.40cm, 3.91cm, 2.34cm and 5.17cm in radial (R), along-track (T), cross-track (N) and 3D directions respectively; If we use the accelerometer observation instead of non-conservative perturbation model, the average accuracy of the orbit is 1.82cm, 2.51cm, 3.48cm and 4.68cm in R, T, N and 3D directions respectively. The result shows that if we use accelerometer observation instead of the non-conservative perturbation model, the accuracy of orbit is better. (2) When we use the reduced-dynamic POD method to get the orbits, the average accuracy of the orbit is 0.80cm, 1.36cm, 2.38cm and 2.87cm in R, T, N and 3D directions respectively. This method is carried out by setting up the pseudo-stochastic pulses to absorb the errors of atmospheric drag and other perturbations. (3) If we use the kinematic POD method, the accuracy of the GRACE orbit is 2.92cm, 2.48cm, 2.76cm and 4.75cm in R, T, N and 3D directions respectively. In conclusion, it can be seen that the POD of GRACE satellite is practicable by using different strategies and methods. The orbit solution is well and stable, they all can obtain the GRACE orbits with centimeter-level precision.

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Integer Ambiguity Resolution on Undifferenced GPS Phase Measurements and Its Application to PPP and Satellite Precise Orbit Determination

Navigation ◽

10.1002/j.2161-4296.2009.tb01750.x ◽

2009 ◽

Vol 56 (2) ◽

pp. 135-149 ◽

Cited By ~ 223

Author(s):

DENIS LAURICHESSE ◽

FLAVIEN MERCIER ◽

JEAN-PAUL BERTHIAS ◽

PATRICK BROCA ◽

LUCA CERRI

Keyword(s):

Ambiguity Resolution ◽

Orbit Determination ◽

Precise Orbit Determination ◽

Integer Ambiguity Resolution ◽

Integer Ambiguity ◽

Phase Measurements ◽

Precise Orbit

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Kinematic and reduced-dynamic precise orbit determination of low earth orbiters

Advances in Geosciences ◽

10.5194/adgeo-1-47-2003 ◽

2003 ◽

Vol 1 ◽

pp. 47-56 ◽

Cited By ~ 92

Author(s):

D. Švehla ◽

M. Rothacher

Keyword(s):

Ambiguity Resolution ◽

Orbit Determination ◽

Precise Orbit Determination ◽

Double Difference ◽

Phase Measurements ◽

Precise Orbit ◽

First Results ◽

Orbit Dynamic ◽

Reduced Dynamic

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

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Precise Orbit Determination of Combined GNSS and LEO Constellations with Regional Ground Stations

Proceedings of the 30th International Technical Meeting of The Satellite Division of the Institute of Navigation (ION GNSS+ 2017) ◽

10.33012/2017.15329 ◽

2017 ◽

Author(s):

Bofeng Li ◽

Liangwei Nie ◽

Haibo Ge ◽

Maorong Ge ◽

Ling Yang

Keyword(s):

Orbit Determination ◽

Precise Orbit Determination ◽

Precise Orbit

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General relativistic effects acting on the orbits of Galileo satellites

Celestial Mechanics and Dynamical Astronomy ◽

10.1007/s10569-021-10014-y ◽

2021 ◽

Vol 133 (4) ◽

Author(s):

K. Sośnica ◽

G. Bury ◽

R. Zajdel ◽

K. Kazmierski ◽

J. Ventura-Traveset ◽

...

Keyword(s):

General Relativity ◽

Orbit Determination ◽

Final Height ◽

Precise Orbit Determination ◽

Satellite System ◽

De Sitter ◽

Circular Orbits ◽

Precise Orbit ◽

Artificial Earth Satellites ◽

Artificial Earth

AbstractThe first pair of satellites belonging to the European Global Navigation Satellite System (GNSS)—Galileo—has been accidentally launched into highly eccentric, instead of circular, orbits. The final height of these two satellites varies between 17,180 and 26,020 km, making these satellites very suitable for the verification of the effects emerging from general relativity. We employ the post-Newtonian parameterization (PPN) for describing the perturbations acting on Keplerian orbit parameters of artificial Earth satellites caused by the Schwarzschild, Lense–Thirring, and de Sitter general relativity effects. The values emerging from PPN numerical simulations are compared with the approximations based on the Gaussian perturbations for the temporal variations of the Keplerian elements of Galileo satellites in nominal, near-circular orbits, as well as in the highly elliptical orbits. We discuss what kinds of perturbations are detectable using the current accuracy of precise orbit determination of artificial Earth satellites, including the expected secular and periodic variations, as well as the constant offsets of Keplerian parameters. We found that not only secular but also periodic variations of orbit parameters caused by general relativity effects exceed the value of 1 cm within 24 h; thus, they should be fully detectable using the current GNSS precise orbit determination methods. Many of the 1-PPN effects are detectable using the Galileo satellite system, but the Lense–Thirring effect is not.

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A Second-Order Time-Difference Position Constrained Reduced-Dynamic Technique for the Precise Orbit Determination of LEOs Using GPS

Remote Sensing ◽

10.3390/rs13153033 ◽

2021 ◽

Vol 13 (15) ◽

pp. 3033

Author(s):

Hui Wei ◽

Jiancheng Li ◽

Xinyu Xu ◽

Shoujian Zhang ◽

Kaifa Kuang

Keyword(s):

Orbit Determination ◽

Dynamic Models ◽

Precise Orbit Determination ◽

Second Order ◽

Time Difference ◽

Error Sources ◽

Precise Orbit ◽

Unmodeled Dynamic ◽

Reduced Dynamic

In this paper, we propose a new reduced-dynamic (RD) method by introducing the second-order time-difference position (STP) as additional pseudo-observations (named the RD_STP method) for the precise orbit determination (POD) of low Earth orbiters (LEOs) from GPS observations. Theoretical and numerical analyses show that the accuracies of integrating the STPs of LEOs at 30 s intervals are better than 0.01 m when the forces (<10−5 ms−2) acting on the LEOs are ignored. Therefore, only using the Earth’s gravity model is good enough for the proposed RD_STP method. All unmodeled dynamic models (e.g., luni-solar gravitation, tide forces) are treated as the error sources of the STP pseudo-observation. In addition, there are no pseudo-stochastic orbit parameters to be estimated in the RD_STP method. Finally, we use the RD_STP method to process 15 days of GPS data from the GOCE mission. The results show that the accuracy of the RD_STP solution is more accurate and smoother than the kinematic solution in nearly polar and equatorial regions, and consistent with the RD solution. The 3D RMS of the differences between the RD_STP and RD solutions is 1.93 cm for 1 s sampling. This indicates that the proposed method has a performance comparable to the RD method, and could be an alternative for the POD of LEOs.

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Assessment of single-difference and track-to-track ambiguity resolution in LEO precise orbit determination

GPS Solutions ◽

10.1007/s10291-021-01103-4 ◽

2021 ◽

Vol 25 (2) ◽

Author(s):

Xingyu Zhou ◽

Hua Chen ◽

Wenlan Fan ◽

Xiaohui Zhou ◽

Qusen Chen ◽

...

Keyword(s):

Ambiguity Resolution ◽

Orbit Determination ◽

Precise Orbit Determination ◽

Precise Orbit ◽

Single Difference

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A More Reliable Orbit Initialization Method for LEO Precise Orbit Determination Using GNSS

Remote Sensing ◽

10.3390/rs12213646 ◽

2020 ◽

Vol 12 (21) ◽

pp. 3646

Author(s):

Xuewen Gong ◽

Jizhang Sang ◽

Fuhong Wang ◽

Xingxing Li

Keyword(s):

Parameter Estimation ◽

Orbit Determination ◽

High Reliability ◽

Precise Orbit Determination ◽

Direct Approach ◽

Design Matrix ◽

Reference Orbit ◽

Stability Analyses ◽

Precise Orbit ◽

Orbit Parameter

Precise orbit determination (POD) using GNSS has been rapidly developed and is the mainstream technology for the navigation of low Earth orbit (LEO) satellites. The initialization of orbit parameters is a key prerequisite for LEO POD processing. For a LEO satellite equipped with a GNSS receiver, sufficient discrete kinematic positions can be obtained easily by processing space-borne GNSS data, and its orbit parameters can thus be estimated directly in iterative manner. This method of direct iterative estimation is called as the direct approach, which is generally considered highly reliable, but in practical applications it has risk of failure. Stability analyses demonstrate that the direct approach is sensitive to oversized errors in the starting velocity vector at the reference time, which may lead to large errors in design matrix because the reference orbit may be significantly distorted, and eventually cause the divergence of the orbit parameter estimation. In view of this, a more reliable method, termed the progressive approach, is presented in this paper. Instead of estimating the orbit parameters directly, it first fits the discrete kinematic positions to a reference ephemeris in the form of the GNSS broadcast ephemeris, which construct a reference orbit that is smooth and close to the true orbit. Based on the reference orbit, the starting orbit parameters are computed in sufficient accuracy, and then the final orbit parameters are estimated with a high accuracy by using discrete kinematic positions as measurements. The stability analyses show that the design matrix errors are reduced in the progressive approach, which would assure more robust orbit parameter estimation than the direct estimation approach. Various orbit initialization experiments are performed on the KOMPSAT-5 and FY3C satellites. The results have fully verified the high reliability of the proposed progressive approach.

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