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Galileo and QZSS precise orbit and clock determination using new satellite metadata / Xingxing Li in Journal of geodesy, vol 93 n° 8 (August 2019)
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Titre : Galileo and QZSS precise orbit and clock determination using new satellite metadata Type de document : Article/Communication Auteurs : Xingxing Li, Auteur ; Yongqiang Yuan, Auteur ; Jiande Huang, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 1123 - 1136 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] Capacité opérationnelle totale
[Termes descripteurs IGN] centre de phase
[Termes descripteurs IGN] constellation Galileo
[Termes descripteurs IGN] données satellitaires
[Termes descripteurs IGN] GIOVE (satellite)
[Termes descripteurs IGN] horloge du satellite
[Termes descripteurs IGN] lacet
[Termes descripteurs IGN] métadonnées
[Termes descripteurs IGN] modèle d'orbite
[Termes descripteurs IGN] orbite précise
[Termes descripteurs IGN] orbitographie
[Termes descripteurs IGN] Quasi-Zenith Satellite System
[Termes descripteurs IGN] rayonnement solaire
[Termes descripteurs IGN] variance d'AllanRésumé : (auteur) During 2016–2018, satellite metadata/information including antenna parameters, attitude laws and physical characteristics such as mass, dimensions and optical properties were released for Galileo and QZSS (except for the QZS-1 optical coefficients). These metadata are critical for improving the accuracy of precise orbit and clock determination. In this contribution, we evaluate the benefits of these new metadata to orbit and clock in three aspects: the phase center offsets and variations (PCO and PCV), the yaw-attitude model and solar radiation pressure (SRP) model. The updating of Galileo PCO and PCV corrections, from the values estimated by Deutsches Zentrum für Luft- und Raumfahrt and Deutsches GeoForschungsZentrum to the chamber calibrations disclosed by new metadata, has only a slight influence on Galileo orbits, with overlap differences within only 1 mm. By modeling the yaw attitude of Galileo satellites and QZS-2 spacecraft (SVN J002) according to new published attitude laws, the residuals of ionosphere-free carrier-phase combinations can be obviously decreased in yaw maneuver seasons. With the new attitude models, the 3D overlap RMS in eclipse seasons can be decreased from 12.3 cm, 14.7 cm, 16.8 cm and 34.7 cm to 11.7 cm, 13.4 cm, 15.8 cm and 32.9 cm for Galileo In-Orbit Validation (IOV), Full Operational Capability (FOC), FOC in elliptical orbits (FOCe) and QZS-2 satellites, respectively. By applying the a priori box-wing SRP model with new satellite dimensions and optical coefficients, the 3D overlap RMS are 5.3 cm, 6.2 cm, 5.3 cm and 16.6 cm for Galileo IOV, FOCe, FOC and QZS-2 satellites, with improvements of 11.0%, 14.7%, 14.0% and 13.8% when compared with the updated Extended CODE Orbit Model (ECOM2). The satellite laser ranging (SLR) validation reveals that the a priori box-wing model has smaller mean biases of − 0.4 cm, − 0.4 cm and 0.6 cm for Galileo FOCe, FOC and QZS-2 satellites, while a slightly larger mean bias of − 1.0 cm is observed for Galileo IOV satellites. Moreover, the SLR residual dependencies of Galileo IOV and FOC satellites on the elongation angle almost vanish when the a priori box-wing SRP model is applied. As for satellite clocks, a visible bump appears in the Modified Allan deviation at integration time of 20,000 s for Galileo Passive Hydrogen Maser with ECOM2, while it almost vanishes when the a priori box-wing SRP model and new metadata are applied. The standard deviations of clock overlap can also be significantly reduced by using new metadata. Numéro de notice : A2019-383 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-019-01230-4 date de publication en ligne : 02/02/2019 En ligne : https://doi.org/10.1007/s00190-019-01230-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93462
in Journal of geodesy > vol 93 n° 8 (August 2019) . - pp 1123 - 1136[article]Assessing the latest performance of Galileo-only PPP and the contribution of Galileo to Multi-GNSS PPP / Fengyu Xiu in Advances in space research, vol 63 n° 9 (1 May 2019)
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Titre : Assessing the latest performance of Galileo-only PPP and the contribution of Galileo to Multi-GNSS PPP Type de document : Article/Communication Auteurs : Fengyu Xiu, Auteur ; Shirong Ye, Auteur ; Pengfei Xia, Auteur ; Lewen Zhao, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 2784 - 2795 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] constellation Galileo
[Termes descripteurs IGN] erreur systématique inter-systèmes
[Termes descripteurs IGN] GalileoSat
[Termes descripteurs IGN] positionnement cinématique
[Termes descripteurs IGN] positionnement par Galileo
[Termes descripteurs IGN] positionnement par GLONASS
[Termes descripteurs IGN] positionnement par GPS
[Termes descripteurs IGN] positionnement ponctuel précis
[Termes descripteurs IGN] précision du positionnement
[Termes descripteurs IGN] résidu
[Termes descripteurs IGN] trajet multiple
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) By the end of 2016, the Galileo constellation had 4 in-orbit validation (IOV) satellites and 14 full operational capability (FOC) satellites, 17 of which were able to transmit signal in November 2017. Galileo has already had early operational capability (EOC). To assess the latest performance of the Galileo-only precise point positioning (PPP) and the contribution of Galileo to the Multi-GNSS PPP solutions, observations collected at 16 Multi-GNSS Experiment (MGEX) stations over ten days are used to realize the various PPP cases. The statistical results show that the three-dimensional positioning accuracy of Galileo static and kinematic PPP can reach centimeter level and decimeter level after convergence, respectively. The contribution of Galileo can improve the positioning accuracy by 29.49%, 29.96% and 23.70% for GPS kinematic PPP and 11.03%, 10.59% and 11.07% for GPS/GLONASS kinematic PPP solutions in the north, east and up components, respectively. The average convergence time can be reduced by 45.48% for GPS-only kinematic PPP and by 11.04% for GPS/GLONASS solutions by adding Galileo observations. Moreover, adding Galileo observations shortens the average convergence time by 30.45% and 7.8% for GPS-only and GPS/GLONASS static PPP solutions, respectively. Although the convergent positioning results of GPS and GPS/GLONASS static PPP solutions after the addition of Galileo measurements do not demonstrate as significant improvement as those of the kinematic PPP solutions, the positioning accuracy of the GPS/Galileo static PPP solutions compared to the GPS-only static PPP still demonstrates an improvement of approximately 25% on the east component. Furthermore, the GPS/Galileo internal system time bias (ISB) and observation residual are analyzed. The results show that the noise level of the GPS L1/L2 signals and the negative impact of multipath errors on the GPS pseudo-range observations for the L1/L2 signals are greater than those of Galileo E1/E5a signals, resulting in the residuals of GPS ionosphere-free code observations larger than those of Galileo code observations. However, the phase observation residuals of GPS and Galileo are of the same magnitude. Additionally, the one-day GPS/Galileo ISB is quite stable. Its stability described by standard deviation is approximately 0.34 ns. Numéro de notice : A2019-397 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2018.06.008 date de publication en ligne : 28/06/2019 En ligne : https://doi.org/10.1016/j.asr.2018.06.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93508
in Advances in space research > vol 63 n° 9 (1 May 2019) . - pp 2784 - 2795[article]Influence of subdaily model for polar motion on the estimated GPS satellite orbits / Natalia Panafidina in Journal of geodesy, vol 93 n° 2 (February 2019)
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Titre : Influence of subdaily model for polar motion on the estimated GPS satellite orbits Type de document : Article/Communication Auteurs : Natalia Panafidina, Auteur ; Urs Hugentobler, Auteur ; Manuela Seitz, Auteur Année de publication : 2019 Article en page(s) : pp 229 - 240 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes descripteurs IGN] analyse diachronique
[Termes descripteurs IGN] élément orbital
[Termes descripteurs IGN] erreur systématique
[Termes descripteurs IGN] International Terrestrial Reference Frame
[Termes descripteurs IGN] marée océanique
[Termes descripteurs IGN] mouvement du géocentre
[Termes descripteurs IGN] mouvement du pôle
[Termes descripteurs IGN] orbite
[Termes descripteurs IGN] positionnement par GPS
[Termes descripteurs IGN] rotation de la Terre
[Termes descripteurs IGN] satellite GPS
[Termes descripteurs IGN] traitement du signalRésumé : (auteur) In this contribution, it is shown that GPS orbits are able to absorb some diurnal signals in polar motion. The arising implications for the influence of the subdaily pole model on GPS solutions are discussed. Two signals in polar motion can be absorbed by GPS orbits: a retrograde signal with a period of a sidereal day (23 h 56 min 4 s) and a prograde signal with a period matching the revolution period of the GPS satellites in the terrestrial reference frame (23 h 55 min 56 s). We show that the retrograde signal contributes to the absolute orientation of the orbital planes in space and the prograde signal, due to coincidence of its period with the period of revolution of the GPS satellites, contributes to the position of the geocenter for each individual satellite. It is known from previous studies that there are systematic differences between orbital parameters from GPS solutions computed with different subdaily pole models. We show in this paper that this behavior can be explained by the absorption effects in 1-day GPS orbits. Diurnal signals cannot be spectrally separated over a time interval of 1 day. Adjustment of any diurnal prograde or retrograde signal to a subdaily pole time series given by a subdaily model over 24 h will lead to an estimated signal with a nonzero amplitude. Thus, any subdaily pole model used in the processing of space geodetic observations contains a part which corresponds numerically to the discussed prograde signal and a part which corresponds to the retrograde diurnal signal. Different pole models show different amplitudes of the diurnal signals which will be absorbed by the orbits. As a result, GPS orbits computed with different subdaily pole models have systematically different orientation and position in space. Using 1-day GPS solutions over a time span of 13 years (1994–2007), we show that the systematic variations in orbit position and orientation caused by individual tidal terms in polar motion can be well predicted and explained by the suggested mechanism. Numéro de notice : A2019-080 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1153-z date de publication en ligne : 24/05/2018 En ligne : https://doi.org/10.1007/s00190-018-1153-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92198
in Journal of geodesy > vol 93 n° 2 (February 2019) . - pp 229 - 240[article]LEO enhanced Global Navigation Satellite System (LeGNSS) for real-time precise positioning services / Bofeng Li in Advances in space research, vol 63 n° 1 (1 January 2019)
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Titre : LEO enhanced Global Navigation Satellite System (LeGNSS) for real-time precise positioning services Type de document : Article/Communication Auteurs : Bofeng Li, Auteur ; Haibo Ge, Auteur ; Maorong Ge, Auteur ; Liangwei Nie, Auteur ; Yunzhong Shen, Auteur ; Harald Schuh, Auteur Année de publication : 2019 Article en page(s) : pp 73 - 93 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] affaiblissement géométrique de la précision
[Termes descripteurs IGN] étude de faisabilité
[Termes descripteurs IGN] orbitographie
[Termes descripteurs IGN] positionnement ponctuel précis
[Termes descripteurs IGN] satellite de télécommunication
[Termes descripteurs IGN] simulation
[Termes descripteurs IGN] temps réelMots-clés libres : LEO constellation enhanced GNSS Résumé : (Auteur) Global Navigation Satellite System (GNSS) has been widely used in many geosciences areas with its Positioning, Navigation and Timing (PNT) service. However, GNSS still has its own bottleneck, such as the long initialization period of Precise Point Positioning (PPP) without dense reference network. Recently, the concept of PNTRC (Positioning, Navigation, Timing, Remote sensing and Communication) has been put forward, where Low Earth Orbit (LEO) satellite constellations are recruited to fulfill diverse missions. In navigation aspect, a number of selected LEO satellites can be equipped with a transmitter to transmit similar navigation signals to ground users, so that they can serve as GNSS satellites but with much faster geometric change to enhance GNSS capability, which is named as LEO constellation enhanced GNSS (LeGNSS). As a result, the initialization time of PPP is expected to be shortened to the level of a few minutes or even seconds depending on the number of the LEO satellites involved. In this article, we simulate all the relevant data from June 8th to 14th, 2014 and investigate the feasibility of LeGNSS with the concentration on the key issues in the whole data processing for providing real-time PPP service based on a system configuration with fourteen satellites of BeiDou Navigation Satellite System (BDS), twenty-four satellites of the Global Positioning System (GPS), and sixty-six satellites of the Iridium satellite constellations. At the server-end, Precise Orbit Determination (POD) and Precise Clock Estimation (PCE) with various operational modes are investigated using simulated observations. It is found out that GNSS POD with partial LEO satellites is the most practical mode of LeGNSS operation. At the user-end, the Geometry Dilution Of Precision (GDOP) and Signal-In-Space Ranging Error (SISRE) are calculated and assessed for different positioning schemes in order to demonstrate the performance of LeGNSS. Centimeter level SISRE can be achieved for LeGNSS. Numéro de notice : A2019-175 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2018.08.017 date de publication en ligne : 16/08/2018 En ligne : https://doi.org/10.1016/j.asr.2018.08.017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92631
in Advances in space research > vol 63 n° 1 (1 January 2019) . - pp 73 - 93[article]
Titre : Ten years of TerraSAR-X : scientific results Type de document : Monographie Auteurs : Michael Eineder, Editeur scientifique ; Achim Roth, Editeur scientifique ; Alberto Moreira, Editeur scientifique Editeur : Bâle [Suisse] : Multidisciplinary Digital Publishing Institute MDPI Année de publication : 2019 Importance : 422 p. ISBN/ISSN/EAN : 978-3-03897-725-4 Note générale : This book is a printed edition of the Special Issue Ten Years of TerraSAR-X—Scientific Results that was published in the open journal "Remote Sensing" from 2018 to 2019. Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Télédétection
[Termes descripteurs IGN] image radar moirée
[Termes descripteurs IGN] image TerraSAR-X
[Termes descripteurs IGN] interféromètrie par radar à antenne synthétique
[Termes descripteurs IGN] MNS TerraSAR & TanDEM-X
[Termes descripteurs IGN] radar à antenne synthétique
[Termes descripteurs IGN] télédétection en hyperfréquence
[Termes descripteurs IGN] TerraSAR-XRésumé : (Editeur) This Special Issue is a collection of papers addressing the scientific use of data acquired in the course of the TerraSAR-X mission 10 years after launch. The articles deal with the mission itself, the accuracy of the products, with differential interferometry, and with applications in the domains cryosphere, oceans, wetlands, and urban areas. Numéro de notice : 26042 Thématique : IMAGERIE Nature : Monographie DOI : 10.3390/books978-3-03897-725-4 date de publication en ligne : 25/04/2019 En ligne : https://doi.org/10.3390/books978-3-03897-725-4 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93611 GPS satellite clock determination in case of inter-frequency clock biases for triple-frequency precise point positioning / Jiang Guo in Journal of geodesy, vol 92 n° 10 (October 2018)
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PermalinkPrecise orbit determination of the Sentinel-3A altimetry satellite using ambiguity-fixed GPS carrier phase observations / Olivier Montenbruck in Journal of geodesy, vol 92 n° 7 (July 2018)
PermalinkCartographier le relief sous les forêts, et le substrat sous les déserts de sable : les attentes de la mission radar Biomass / Laurent Polidori in XYZ, n° 154 (mars - mai 2018)
PermalinkCaractérisation et qualification de Modèles Numériques de Surfaces (MNS) - Analyse de la cohérence avec des masques d’eau / Guillaume Sutter (2018)
PermalinkInSAR data for geohazard assessment in UNESCO World Heritage sites: state-of-the-art and perspectives in the Copernicus era / Deodato Tapete in International journal of applied Earth observation and geoinformation, vol 63 (December 2017)
PermalinkA fast cloud detection algorithm applicable to monitoring and nowcasting of daytime cloud systems / Xiao-Yong Zhuge in IEEE Transactions on geoscience and remote sensing, vol 55 n° 11 (November 2017)
PermalinkPrecise orbit determination of the Fengyun-3C satellite using onboard GPS and BDS observations / Min Li in Journal of geodesy, vol 91 n° 11 (November 2017)
PermalinkExamination of Sentinel-2A multi-spectral instrument (MSI) reflectance anisotropy and the suitability of a general method to normalize MSI reflectance to nadir BRDF adjusted reflectance / David P. Roy in Remote sensing of environment, vol 199 (15 September 2017)
PermalinkComparison 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)
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