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The DORIS network: Advances achieved in the last fifteen years / Jérôme Saunier in Advances in space research, vol inconnu (2023)
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Titre : The DORIS network: Advances achieved in the last fifteen years Type de document : Article/Communication Auteurs : Jérôme Saunier , Auteur Année de publication : 2023 Projets : 1-Pas de projet / Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] DORISRésumé : (auteur) The Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) system is based on a homogeneous global geodetic network. The DORIS ground network is managed and monitored by a core group (CNES & IGN), which made it possible to closely steer its deployment and evolution. Thanks to infrastructure and hardware enhancements, the DORIS network has continuously improved over time in order to meet the performance requirements of satellite altimetry but also strengthen its role as geodetic network to contribute to the International Terrestrial Reference Frame (ITRF). Following the review by Fagard (2006) of the network from its initial deployment to its renovation, this paper aims at showing the advances achieved in the last fifteen years (2006–2021) to better serve the needs for precise orbit determination and geodesy. After reminding the historical background and the different stages of the network development, we zoom in the last decade that enabled the network to achieve improved operability thanks to infrastructure standardization, permanent monitoring and ongoing assessment. Today, the numerous strengths and assets of the DORIS network built up over 30 years give it an important role in contributing to Earth Sciences. This review shows the progress achieved in terms of geographical coverage, co-location with other techniques, data availability, stations equipment, monument stability, and system requirements compliance. Finally, we give an overview of the future prospects and new challenges to continue improvements in the DORIS technique. Numéro de notice : A2023-082 Affiliation des auteurs : IGN (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2022.07.016 En ligne : https://doi.org/10.1016/j.asr.2022.07.016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101340
in Advances in space research > vol inconnu (2023)[article]The international DORIS service contribution to ITRF2020 / Guilhem Moreaux in Advances in space research, vol inconnu (2023)
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Titre : The international DORIS service contribution to ITRF2020 Type de document : Article/Communication Auteurs : Guilhem Moreaux, Auteur ; Franck G. Lemoine, Auteur ; Hugues Capdeville, Auteur ; Michiel Otten, Auteur ; Petr Štěpánek, Auteur ; Jérôme Saunier , Auteur ; Pascale Ferrage, Auteur Année de publication : 2023 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] combinaison au niveau des observations
[Termes IGN] DORIS
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] mouvement du pôleRésumé : (autuer) For the realization of the 2020 International Terrestrial Reference Frame (ITRF2020), the International DORIS Service delivered to the International Earth Rotation and Reference Systems Service (IERS) a set of 1456 weekly solution files from 1993.0 to 2021.0 including station coordinates and Earth orientation parameters (EOPs). The data come from fourteen DORIS satellites: TOPEX/Poseidon, SPOT-2, SPOT-3, SPOT-4, SPOT-5, Envisat, Jason-1, Jason-2, Cryosat-2, Saral, HY-2A, Jason-3, Sentinel-3A and Sentinel-3B. In their processing, the four analysis centers which contributed to the DORIS combined solution used the latest time variable gravity models, the new mean pole and diurnal-subdiurnal tidal EOP models recommended by IERS. In addition, all the analysis centers included in their processing precise SPOT-5 solar panel angle values and quaternions for, at least, the Jason satellites. Furthermore, a new Alcatel phase center variation model was implemented for the ITRF2020 processing. The main objective of this study is to present the combination process and to analyze the impact of the new modeling on the performance of the new combined solution. Comparisons with the IDS contribution to ITRF2014 show that i) the application of the new phase center variations for the Alcatel DORIS ground antennas in the data processing combined with the gradual replacement over time of the Alcatel by Starec antennas implies a scale drift from 1993.0 to 2002.5 and ii) thanks to a better modeling of the surface forces on the satellites, the new combined solution shows smaller annual and 118-day signals in the geocenter. A new DORIS terrestrial reference frame was computed to evaluate the intrinsic quality of the new combined solution. That evaluation shows that over almost the full time span the intrinsic IDS scale values lie in a range of mm. After mid-2008, the new DORIS reference frame has an internal position consistency in North-East-Up better than 7.5 mm. Numéro de notice : A2023-083 Affiliation des auteurs : IGN+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2022.07.012 Date de publication en ligne : 15/07/2022 En ligne : https://doi.org/10.1016/j.asr.2022.07.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101349
in Advances in space research > vol inconnu (2023)[article]ITRF2020: an augmented reference frame refining the modeling of nonlinear station motions / Zuheir Altamimi in Journal of geodesy, vol 97 n° 5 (May 2023)
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Titre : ITRF2020: an augmented reference frame refining the modeling of nonlinear station motions Type de document : Article/Communication Auteurs : Zuheir Altamimi , Auteur ; Paul Rebischung , Auteur ; Xavier Collilieux , Auteur ; Laurent Métivier , Auteur ; Kristel Chanard , Auteur Année de publication : 2023 Article en page(s) : n° 47 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] International Terrestrial Reference FrameRésumé : (auteur) To better describe the shape of the constantly deforming Earth’s surface, the ITRF2020 is provided as an augmented terrestrial reference frame that precisely models nonlinear station motions for both seasonal (annual and semi-annual) signals present in the station position time series and Post-Seismic Deformation (PSD) for sites impacted by major earthquakes. Reprocessed solutions in the form of station position time series and Earth Orientation Parameters using the full observation history provided by the four space geodetic techniques (DORIS, GNSS, SLR and VLBI) were used as input data, spanning 28, 27, 38 and 41 years of observations, respectively. The ITRF2020 long-term origin follows linearly with time the Earth’s Center of Mass (CM) as sensed by SLR, based on observations collected over the time span 1993.0–2021.0. We evaluate the accuracy of the ITRF2020 long-term origin position and time evolution by comparison to previous solutions, namely ITRF2014, ITRF2008 and ITRF2005, to be at the level of or better than 5 mm and 0.5 mm/yr, respectively. The ITRF2020 long-term scale is defined by a rigorous weighted average of selected VLBI sessions up to 2013.75 and SLR weekly solutions covering the 1997.75–2021.0 time span. For the first time of the ITRF history, the scale agreement between SLR and VLBI long-term solutions is at the level of 0.15 ppb (1 mm at the equator) at epoch 2015.0, with no drift. To accommodate most of ITRF2020 users, the seasonal station coordinate variations are provided in the CM as well as in the Center of Figure frames, together with a seasonal geocenter motion model. While the PSD parametric models were determined by fitting GNSS data only, they also fit the station position time series of the three other techniques that are colocated with GNSS, demonstrating their high performance in describing site post-seismic trajectories. Numéro de notice : A2023-098 Affiliation des auteurs : UMR IPGP-Géod (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-023-01738-w Date de publication en ligne : 19/05/2023 En ligne : https://doi.org/10.1007/s00190-023-01738-w Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103231
in Journal of geodesy > vol 97 n° 5 (May 2023) . - n° 47[article]Assessment of VRS performances of the Algerian-CORS-network / Takka Elhadi in Bulletin des sciences géographiques, vol 27 n° 1 (2023)
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Titre : Assessment of VRS performances of the Algerian-CORS-network Type de document : Article/Communication Auteurs : Takka Elhadi, Auteur ; Touabet Touabet, Auteur ; Boudrassene Abdennour, Auteur Année de publication : 2023 Article en page(s) : pp 25 - 33 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] affaiblissement géométrique de la précision
[Termes IGN] Algérie
[Termes IGN] disponibilité des données
[Termes IGN] intégrité des données
[Termes IGN] performance
[Termes IGN] précision du positionnement
[Termes IGN] répétabilité
[Termes IGN] réseau géodésique local
[Termes IGN] réseau géodésique permanent
[Termes IGN] station de référenceRésumé : (auteur) The Algerian Continuously Operating Reference Stations Network, so-called AL-CORS-Net, is deployed to provideNRTK services based onVRS method using Geo++GNSMART software.This paper investigates VRS performance in terms ofprecision, availability, integrity, Time-to-Fix-Ambiguity (TTFA), repeatability and PDOP.Several survey sessions were performed at different sites in the north of Algeria during October 2021 to January 2022. The results revealed good performance indicators; the precision was in the order of 1.3 cm in the horizontal component and about 2.2 cm in the vertical (at 1 sigma). The VRS solution's availability was 97.25%, its integrity was 98.8% in the horizontal and 94.9% in the vertical, and the TTFA ranged from a few seconds to a few minutes. The VRS measurements' repeatability presented similar measurement results throughout time. High satellite numbers have been tracked, their geometry (PDOP) was ideal. Numéro de notice : A2023-090 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : https://www.asjp.cerist.dz/en/downArticle/213/27/1/216928 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103152
in Bulletin des sciences géographiques > vol 27 n° 1 (2023) . - pp 25 - 33[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 253-2023011 RAB Revue Centre de documentation En réserve L003 Disponible Documents numériques
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Assessment of VRS performances ... - pdf éditeurAdobe Acrobat PDF Determination of Helmert transformation parameters for continuous GNSS networks: a case study of the Géoazur GNSS network / Dinh Trong Tran in Geo-spatial Information Science, vol 26 n° 1 (March 2023)
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Titre : Determination of Helmert transformation parameters for continuous GNSS networks: a case study of the Géoazur GNSS network Type de document : Article/Communication Auteurs : Dinh Trong Tran, Auteur ; Jean-Mathieu Nocquet , Auteur ; Ngoc Dung Luong, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : pp 125 - 138 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] données GNSS
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] méthode des moindres carrés
[Termes IGN] transformation de coordonnées
[Termes IGN] transformation de Helmert
[Termes IGN] valeur aberranteRésumé : (auteur) In this paper, we propose an approach to determine seven parameters of the Helmert transformation by transforming the coordinates of a continuous GNSS network from the World Geodetic System 1984 (WGS84) to the International Terrestrial Reference Frame. This includes (1) converting the coordinates of common points from the global coordinate system to the local coordinate system, (2) identifying and eliminating outliers by the Dikin estimator, and (3) estimating seven parameters of the Helmert transformation by least squares (LS) estimation with the “clean” data (i.e. outliers removed). Herein, the local coordinate system provides a platform to separate points’ horizontal and vertical components. Then, the Dikin estimator identifies and eliminates outliers in the horizontal or vertical component separately. It is significant because common points in a continuous GNSS network may contain outliers. The proposed approach is tested with the Géoazur GNSS network with the results showing that the Dikin estimator detects outliers at 6 out of 18 common points, among which three points are found with outliers in the vertical component only. Thus, instead of eliminating all coordinate components of these six common points, we only eliminate all coordinate components of three common points and only the vertical component of another three common points. Finally, the classical LS estimation is applied to “clean” data to estimate seven parameters of the Helmert transformation with a significant accuracy improvement. The Dikin estimator’s results are compared to those of other robust estimators of Huber and Theil-Sen, which shows that the Dikin estimator performs better. Furthermore, the weighted total least-squares estimation is implemented to assess the accuracy of the LS estimation with the same data. The inter-comparison of the seven estimated parameters and their standard deviations shows a small difference at a few per million levels (E-6). Numéro de notice : A2023-208 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/10095020.2022.2138569 Date de publication en ligne : 15/11/2022 En ligne : https://doi.org/10.1080/10095020.2022.2138569 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103135
in Geo-spatial Information Science > vol 26 n° 1 (March 2023) . - pp 125 - 138[article]A new algebraic solution for transforming Cartesian to geodetic coordinates / Jia-Chun Guo in Survey review, vol 55 n° 389 (March 2023)PermalinkGENESIS: co-location of geodetic techniques in space / Pacôme Delva in Earth, Planets and Space, vol 75 n° 1 (2023)PermalinkITRF2020 : un référentiel augmenté affinant la modélisation des mouvements non linéaires des stations / Zuheir Altamimi in XYZ, n° 173 (décembre 2022)PermalinkUnification of GNSS CORS coordinates in Thailand / Somchai Kriengkraiwasin in Survey review, vol 54 n° 387 (November 2022)PermalinkAdaptive block modeling of time dependent variations of datum reference points in a tectonically active area / Chun-Yun Chou in Survey review, vol 54 n° 386 (September 2022)PermalinkAutomated detection of discontinuities in EUREF permanent GNSS network stations due to earthquake events / Sergio Baselga in Survey review, vol 54 n° 386 (September 2022)PermalinkDetermination of vertical land movements through the integration of tide gauge observations and satellite altimetry data at the Brazilian Vertical Datum from 2002 to 2015 / Samoel Gehl in Boletim de Ciências Geodésicas, vol 28 n° 2 ([01/07/2022])PermalinkDeformation analysis: the modified GREDOD method / Mehmed Batilović in Geodetski vestnik, vol 66 n° 1 (March 2022)PermalinkPartitions of normalised multiple regression equations for datum transformations / Andrew Carey Ruffhead in Boletim de Ciências Geodésicas, vol 28 n° 1 ([01/03/2022])PermalinkPermalink