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Impact of thermospheric mass density on the orbit prediction of LEO satellites / Changyong He in Space weather, vol 18 n° 1 (January 2020)
[article]
Titre : Impact of thermospheric mass density on the orbit prediction of LEO satellites Type de document : Article/Communication Auteurs : Changyong He , Auteur ; Yang Yang, Auteur ; Brett Anthony Carter, Auteur ; Kefei Zhang, Auteur ; Andong Hu, Auteur ; Wang Li, Auteur ; Florent Deleflie, Auteur ; Robert Norman, Auteur ; Suqin Wu, Auteur Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : n° e2019SW002336 Note générale : bibliographie
This study was supported by the Cooperative Research Centre for Space Environment Management (SERCLimited) through the Australian Government's Cooperative Research Centre Programme and partially supported by the National Natural Science Foundation of China (41874040) and the CUMT Independent Innovation Project of “Double-First Class” Construction (2018ZZCX08)Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] masse d'air
[Termes IGN] orbite basse
[Termes IGN] orbitographieRésumé : (auteur) Many thermospheric mass density (TMD) variations have been recognized in observations and physical simulations; however, their impact on the low‐Earth‐orbit satellites has not been fully evaluated. The present study investigates the quantitative impact of periodic spatiotemporal TMD variations modulated by the empirical DTM2013 model. Also considered are two small‐scale variations, that is, the equatorial mass anomaly and the midnight density maximum, which are reproduced by the Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model. This investigation is performed through a 1‐day orbit prediction (OP) simulation for a 400‐km circular orbit. The results show that the impact of TMD variations during solar maximum is 1 order of magnitude larger than that during solar minimum. The dominant impact has been found in the along‐track direction. Semiannual and semidiurnal variations in TMD exert the most significant impact on OP among the intra‐annual and intradiurnal variations, respectively. The zero mean periodic variations in TMD may not significantly affect the predicted orbit but increase the orbital uncertainty if their periods are shorter than the time span of OP. Additionally, the equatorial mass anomaly creates a mean orbit difference of 50 m (5 m) with a standard deviation of 30 m (3 m) in 1‐day OP during high (low) solar activity. The midnight density maximum exhibits a stronger impact in the order of 150±30 and 15±6 m during solar maximum and solar minimum, respectively. This study makes clear that careful selection of TMD variations is of great importance to balance the trade‐off between efficiency and accuracy in OP problems. Numéro de notice : A2020-467 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2019SW002336 Date de publication en ligne : 06/11/2019 En ligne : https://doi.org/10.1029/2019SW002336 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95553
in Space weather > vol 18 n° 1 (January 2020) . - n° e2019SW002336[article]Comparison of precise orbit determination methods of zero-difference kinematic, dynamic and reduced-dynamic of GRACE-A satellite using SHORDE software / Kai Li in Journal of applied geodesy, vol 11 n° 3 (September 2017)
[article]
Titre : Comparison of precise orbit determination methods of zero-difference kinematic, dynamic and reduced-dynamic of GRACE-A satellite using SHORDE software Type de document : Article/Communication Auteurs : Kai Li, Auteur ; Xuhua Zhou, Auteur ; Nannan Guo, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 157 - 166 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Technologies spatiales
[Termes IGN] coordonnées GPS
[Termes IGN] GRACE
[Termes IGN] mesurage de phase
[Termes IGN] orbite basse
[Termes IGN] orbitographieRésumé : (Auteur) Zero-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. Numéro de notice : A2017-570 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2017-0004 En ligne : https://doi.org/10.1515/jag-2017-0004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86690
in Journal of applied geodesy > vol 11 n° 3 (September 2017) . - pp 157 - 166[article]Precision on board : orbit determination of LEO satellites with real-time corrections / André Hauschild in GPS world, vol 28 n° 4 (April 2017)
[article]
Titre : Precision on board : orbit determination of LEO satellites with real-time corrections Type de document : Article/Communication Auteurs : André Hauschild, Auteur ; Javier Tegedor, Auteur ; Oliver Montenbruck, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 42 - 47 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] éphémérides de satellite
[Termes IGN] orbite basse
[Termes IGN] orbitographie
[Termes IGN] précision du positionnement
[Termes IGN] simulation
[Termes IGN] temps réelRésumé : (Auteur) Precise point positioning (PPP) with real-time orbit and clock correction streams has become an established technique over the past decade. Several free as well as commercial sources of precise correction streams are available through the internet or via a satellite link to geostationary satellites. Many applications exist for land, air and sea applications, but use of real-time corrections for precise positioning has not extended into orbit yet, although a number of low Earth orbit (LEO) satellite missions have a demand for precise orbit determination (POD). Mission requirements often allow for a relatively high latency for the availability of the precise orbit products, thus ground-based, near-real-time processing is sufficient. However, future satellites with altimeter and radio-occultation payloads may require real-time POD to enable onboard processing of science data for short-term forecasting or now-casting of meteorology data, open-loop instrument operations of radar payloads, or quick-look onboard science data generation. Also, precise real-time orbit information may be used for constellation maintenance of satellite formations. Despite early technology readiness demonstrations by the Jet Propulsion Laboratory carried out one decade ago to transmit real-time corrections via geostationary relay satellites to LEO spacecraft, this technique has so far not been implemented and used in a space mission. Numéro de notice : A2017-292 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85327
in GPS world > vol 28 n° 4 (April 2017) . - pp 42 - 47[article]Ionosphere probing with simultaneous GNSS radio occultations / Viet-Cuong Pham in GPS solutions, vol 21 n° 1 (January 2017)
[article]
Titre : Ionosphere probing with simultaneous GNSS radio occultations Type de document : Article/Communication Auteurs : Viet-Cuong Pham, Auteur ; Jyh-Ching Juang, Auteur Année de publication : 2017 Article en page(s) : pp 101 - 109 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] données GNSS
[Termes IGN] gradient ionosphèrique
[Termes IGN] inversion
[Termes IGN] occultation du signal
[Termes IGN] orbite basse
[Termes IGN] régularisation de Tychonoff
[Termes IGN] teneur totale en électronsRésumé : (Auteur) Radio occultation (RO) is a powerful technique for providing vertical profiles of refractivity, temperature, pressure, and water vapor of the neutral atmosphere and electron density of the ionosphere. The Abel inversion method which is based on the spherical symmetry assumption has been widely utilized to retrieve electron density profiles (EDPs) from RO measurements, which are available by observing Global Navigation Satellite System (GNSS) satellites from low-earth-orbit satellites. It is well known that the Abel inversion is subject to errors in the presence of ionospheric horizontal gradients. With the arrival of new navigation systems, the opportunities of establishing simultaneous GNSS RO events are increasing. We develop an improved Abel inversion technique that accounts for pairs of simultaneous RO events to relax the spherical symmetry assumption. Through the use of Tikhonov regularization, the problem is formulated so that numerical conditioning is improved and a priori information such as expected electron density, asymmetric factor, and vertical total electron content can be incorporated. Appropriate weighting can be determined to reflect the availability and quality of information. By balancing the reference data and measurements, the method thus paves a way for ionospheric probing in challenging geomagnetic conditions as both the EDP at the intersection and the horizontal gradients are retrieved. Simulation and experimental results are provided to show the effectiveness of the proposed method. The robustness and sensitivity of the proposed method are also assessed. Numéro de notice : A2017-014 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0501-1 Date de publication en ligne : 02/01/2016 En ligne : http://dx.doi./org/10.1007/s10291-015-0501-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83936
in GPS solutions > vol 21 n° 1 (January 2017) . - pp 101 - 109[article]Assessment of vertical TEC mapping functions for space-based GNSS observations / Jiahao Zhong in GPS solutions, vol 20 n° 3 (July 2016)
[article]
Titre : Assessment of vertical TEC mapping functions for space-based GNSS observations Type de document : Article/Communication Auteurs : Jiahao Zhong, Auteur ; Jiuhou Lei, Auteur ; Xiankang Dou, Auteur ; Xinan Yue, Auteur Année de publication : 2016 Article en page(s) : pp 353 - 362 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] centroïde
[Termes IGN] coordonnées GNSS
[Termes IGN] hauteur de la couche ionosphérique
[Termes IGN] ionosphère
[Termes IGN] orbite basse
[Termes IGN] teneur totale en électrons
[Termes IGN] teneur verticale totale en électronsRésumé : (Auteur) The mapping function is commonly used to convert slant to vertical total electron content (TEC) based on the assumption that the ionospheric electrons concentrate in a layer. The height of the layer is called ionospheric effective height (IEH) or shell height. The mapping function and IEH are generally well understood for ground-based global navigation satellite system (GNSS) observations, but they are rarely studied for the low earth orbit (LEO) satellite-based TEC conversion. This study is to examine the applicability of three mapping functions for LEO-based GNSS observations. Two IEH calculating methods, namely the centroid method based on the definition of the centroid and the integral method based on one half of the total integral, are discussed. It is found that the IEHs increase linearly with the orbit altitudes ranging from 400 to 1400 km. Model simulations are used to compare the vertical TEC converted by these mapping functions and the vertical TEC directly calculated by the model. Our results illustrate that the F&K (Foelsche and Kirchengast) geometric mapping function together with the IEH from the centroid method is more suitable for the LEO-based TEC conversion, though the thin layer model along with the IEH of the integral method is more appropriate for the ground-based vertical TEC retrieval. Numéro de notice : A2016-629 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0444-6 En ligne : http://dx.doi.org/10.1007/s10291-015-0444-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81832
in GPS solutions > vol 20 n° 3 (July 2016) . - pp 353 - 362[article]Absolute IGS antenna phase center model igs08.atx: status and potential improvements / Ralf Schmid in Journal of geodesy, vol 90 n° 4 (April 2016)PermalinkPrecise orbit determination based on raw GPS measurements / Norbert Zehentner in Journal of geodesy, vol 90 n° 3 (March 2016)PermalinkPermalinkUsing ionospheric corrections from the space-based augmentation systems for low earth orbiting satellites / Jeongrae Kim in GPS solutions, vol 19 n° 3 (July 2015)PermalinkAnalysis of orbital configurations for geocenter determination with GPS and low-Earth orbiters / Da Kuang in Journal of geodesy, vol 89 n° 5 (May 2015)PermalinkDetermination of precise satellite orbits and geodetic parameters using satellite laser ranging / Krzysztof Sosnica (2015)PermalinkA technique for routinely updating the ITU-R database using radio occultation electron density profiles / Claudio Brunini in Journal of geodesy, vol 87 n° 9 (September 2013)PermalinkPermalinkGPS-derived orbits for the GOCE satellite / Heike Bock in Journal of geodesy, vol 85 n° 11 (November /2011)PermalinkGlobal gravity field determination using the GPS measurements made onboard the low Earth orbiting satellite CHAMP / Lars Prange (2010)Permalink