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Estimation and analysis of GPS inter-fequency clock biases from long-term triple-frequency observations / Fan Zhang in GPS solutions, vol 25 n° 4 (October 2021)
[article]
Titre : Estimation and analysis of GPS inter-fequency clock biases from long-term triple-frequency observations Type de document : Article/Communication Auteurs : Fan Zhang, Auteur ; Hongzhou Chai, Auteur ; Linyang Li, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 126 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] décalage d'horloge
[Termes IGN] erreur systématique interfréquence d'horloge
[Termes IGN] fréquence multiple
[Termes IGN] phase GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] station GNSS
[Termes IGN] triple différence
[Termes IGN] variation temporelleRésumé : (auteur) Usually, the difference between the satellite clocks computed with L1/L2 and clocks computed with L1/L5 is defined as inter-frequency clock bias (IFCB). It is critical to correct its L5 time-variant portion in the GNSS triple-frequency precise positioning. Using two years of observations from more than 100 stations worldwide, we use the epoch-differenced method to estimate IFCB for all available 12 GPS BLOCK-IIF satellites, and analyze its short-term and long-term variations. The experimental results indicate that the IFCB variations are clearly consistent for two satellites located in the same orbital plane, which perhaps means that the variations of IFCB are dependent on the orbital plane. We found that the IFCB of each Block-IIF satellite shows repetition characteristics over two years. The annual repetition cycle of 352 days of IFCB is consistent with the GPS year 351.4 days may originate from the rotation of satellites around the earth. GPS triple-frequency uncombined PPP is carried out using 9 globally distributed MGEX stations from June 1 to 30, 2018. The experimental results indicate that compared to the PPP solutions without IFCB corrections, GPS triple-frequency PPP can achieve an accuracy of 2.2, 3.8 and 11.4 mm in the north, east, and up components after correcting IFCB, which is an accuracy increase in 31.3%, 17.4%, and 13.0%, respectively. The average RMS of the phase posteriori residuals for each frequency is also reduced significantly, especially 79.1% for L5 frequency. Numéro de notice : A2021-565 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-021-01161-8 Date de publication en ligne : 10/07/2021 En ligne : https://doi.org/10.1007/s10291-021-01161-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98134
in GPS solutions > vol 25 n° 4 (October 2021) . - n° 126[article]Evaluation of methods for connecting InSAR to a terrestrial reference frame in the Latrobe Valley, Australia / P.J. Johnston in Journal of geodesy, vol 95 n° 10 (October 2021)
[article]
Titre : Evaluation of methods for connecting InSAR to a terrestrial reference frame in the Latrobe Valley, Australia Type de document : Article/Communication Auteurs : P.J. Johnston, Auteur ; M. S. Filmer, Auteur ; Thomas Fuhrmann, Auteur Année de publication : 2021 Article en page(s) : n° 115 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] Australian Geodetic Datum
[Termes IGN] Australie
[Termes IGN] Continuously Operating Reference Station network
[Termes IGN] image Sentinel-SAR
[Termes IGN] incertitude de mesurage
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] littoral
[Termes IGN] propagation d'erreur
[Termes IGN] réseau géodésique permanent
[Termes IGN] station GNSS
[Termes IGN] subsidenceRésumé : (auteur) Deformation measurements from satellite-borne synthetic aperture radar interferometry (InSAR) are usually measured relative to an arbitrary reference point (RP) of assumed stability over time. For InSAR rates to be reliably interpreted as uplift or subsidence, they must be connected to a defined Earth-centred terrestrial reference frame (TRF), usually made through GNSS continuously operating reference stations (CORS). We adapt and compare three methods of TRF connection proposed by different studies which we term the single CORS RP (SCRP), plane-fit multiple CORS (PFMC), and the multiple CORS RP (MCRP). We generalise equations for these methods, and importantly, develop equations to propagate InSAR and GNSS uncertainties through the transformation process. This is significant, because it is important to not only estimate the InSAR uncertainties, but also to account for the uncertainties that are introduced when connecting to the CORS so as to better inform our interpretation of the deformation field and the limitation of the measurements. We then test these methods using Sentinel-1 data in the Latrobe Valley, Australia. These results indicate that differences among the three TRF connection methods may be greater than their estimated uncertainties. MCRP appears the most reliable method, although it may be limited in large study areas with sparse CORS due to long wavelength InSAR errors and that gaps and/or steps may appear at the spatial limit from the CORS. SCRP relies on the quality of the single CORS connection, but can be validated by unconnected CORS in the study area. The PFMC method is suited to larger areas undergoing slow, constant deformation covering large spatial extents where there are evenly distributed CORS across the study area. Selecting an optimal method of TRF connection is dependent on local site conditions, CORS network geometry and the characteristics of the deformation field. Hence, the choice of TRF connection method should be carefully considered, because different methods may result in significantly different transformed deformation rates. We confirm slow subsidence across the Latrobe Valley relative to the vertical component of the ITRF2014, with localised high subsidence rates near open cut mining activities. Subsidence of ~ -6 mm/year is observed in the adjacent coastal region which may exacerbate relative sea level rise along the coastline, increasing future risks of coastal inundation. Numéro de notice : A2021-749 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s00190-021-01560-2 Date de publication en ligne : 08/10/2021 En ligne : https://doi.org/10.1007/s00190-021-01560-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98730
in Journal of geodesy > vol 95 n° 10 (October 2021) . - n° 115[article]Urban geospatial information acquisition mobile mapping system based on close-range photogrammetry and IGS site calibration / Ming Guo in Geo-spatial Information Science, vol 24 n° 4 (October 2021)
[article]
Titre : Urban geospatial information acquisition mobile mapping system based on close-range photogrammetry and IGS site calibration Type de document : Article/Communication Auteurs : Ming Guo, Auteur ; Yuquan Zhou, Auteur ; Jianghong Zhao, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 558 - 579 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie terrestre
[Termes IGN] coordonnées GNSS
[Termes IGN] couplage GNSS-INS
[Termes IGN] données lidar
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] orientation du capteur
[Termes IGN] précision des mesures
[Termes IGN] Ransac (algorithme)
[Termes IGN] semis de points
[Termes IGN] station GNSS
[Termes IGN] système de numérisation mobile
[Termes IGN] zone urbaineRésumé : (auteur) The measurement accuracy of the Mobile Mapping System (MMS) is the main problem, which restricts its development and application, so how to calibrate the MMS to improve its measurement accuracy has always been a research hotspot in the industry. This paper proposes a position and attitude calibration method with error correction based on the combination of the feature point and feature surface. First, the initial value of the spatial position relationship between each sensor of MMS is obtained by close-range photogrammetry. Second, the optimal solution for error correction is calculated by feature points in global coordinates jointly measured with International GNSS Service (IGS) stations. Then, the final transformation parameters are solved by combining the initial values obtained originally, thereby realizing the rapid calibration of the MMS. Finally, it analyzed the RMSE of MMS point cloud after calibration, and the results demonstrate the feasibility of the calibration approach proposed by this method. Under the condition of a single measurement sensor accuracy is low, the plane and elevation absolute accuracy of the point cloud after calibration can reach 0.043 m and 0.072 m, respectively, and the relative accuracy is smaller than 0.02 m. It meets the precision requirements of data acquisition for MMS. It is of great significance for promoting the development of MMS technology and the application of some novel techniques in the future, such as autonomous driving, digital twin city, urban brain et al. Numéro de notice : A2021-128 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/10095020.2021.1924084 Date de publication en ligne : 20/08/2021 En ligne : https://doi.org/10.1080/10095020.2021.1924084 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99354
in Geo-spatial Information Science > vol 24 n° 4 (October 2021) . - pp 558 - 579[article]Ten years of Lake Taupō surface height estimates using the GNSS interferometric reflectometry / Lucas D. Holden in Journal of geodesy, vol 95 n° 7 (July 2021)
[article]
Titre : Ten years of Lake Taupō surface height estimates using the GNSS interferometric reflectometry Type de document : Article/Communication Auteurs : Lucas D. Holden, Auteur ; Kristine M. Larson, Auteur Année de publication : 2021 Article en page(s) : n° 74 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] altimétrie satellitaire par radar
[Termes IGN] lac
[Termes IGN] Nouvelle-Zélande
[Termes IGN] réflectométrie par GNSS
[Termes IGN] série temporelle
[Termes IGN] signal GNSS
[Termes IGN] station GNSSRésumé : (auteur) A continuously operating GNSS station within a lake interior is uncommon, but advantageous for testing the GNSS Interferometric Reflectometry (GNSS-IR) technique. In this research, GNSS-IR is used to estimate ten years of lake surface heights for Lake Taupō in New Zealand. This is achieved using data collected from station TGHO, approximately 4 km from the lake’s shoreline. Its reliability is assessed by comparisons with shoreline gauges and satellite radar altimetry lake surface heights. Relative RMS differences between the daily averaged lake gauge and GNSS-IR lake surface heights range from ± 0.027 to ± 0.028 m. Relative RMS differences between the satellite radar altimetry lake surface heights and the GNSS-IR lake surface heights are ± 0.069 m and ± 0.124 m. The results show that the GNSS-IR technique at Lake Taupō can provide reliable lake surface height estimates in a terrestrial reference frame. A new ground-based absolute satellite radar altimetry calibration/validation approach based on GNSS-IR is proposed and discussed. Numéro de notice : A2021-513 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-021-01523-7 Date de publication en ligne : 18/06/2021 En ligne : https://doi.org/10.1007/s00190-021-01523-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97932
in Journal of geodesy > vol 95 n° 7 (July 2021) . - n° 74[article]Récepteurs GNSS bas coût pour la surveillance des grands ponts / Nicolas Manzini in XYZ, n° 167 (juin 2021)
[article]
Titre : Récepteurs GNSS bas coût pour la surveillance des grands ponts Type de document : Article/Communication Auteurs : Nicolas Manzini, Auteur ; André Orcesi, Auteur ; Christian Thom , Auteur ; Marc-Antoine Brossault, Auteur ; Miguel Ortiz, Auteur ; Serge Botton , Auteur ; John Dumoulin, Auteur Année de publication : 2021 Article en page(s) : pp 39 - 44 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] analyse spatio-temporelle
[Termes IGN] Géocube
[Termes IGN] pont
[Termes IGN] qualité des données
[Termes IGN] récepteur GNSS
[Termes IGN] Seine-maritime (76)
[Termes IGN] station GNSS
[Termes IGN] surveillance d'ouvrageRésumé : (Auteur) L’instrumentation et la télésurveillance des structures, qui visent à suivre en continu et en temps réel l’évolution de leurs comportements, sont aujourd’hui des éléments clés des politiques de gestion des parcs d’ouvrages. Le conseil départemental de la Seine-Maritime (76) a fait appel à l’IGN (Institut national de l'information géographique et forestière) pour instrumenter le pont de Brotonne à l’aide d’un réseau d’une douzaine de stations GNSS “bas coût” Géocube à partir de 2017. L’objectif de cette instrumentation est de compléter le suivi géométrique de l’ouvrage assuré par des relevés topographiques périodiques. Dans le cadre d’un projet de recherche en collaboration entre SITES, l’Université Gustave Eiffel et l’IGN, visant à étudier le potentiel des outils GNSS pour la surveillance de santé structurale des ouvrages d’art, les données acquises sur le pont de Brotonne sur la période 2017-2018 ont été analysées. Dans cet article, nous proposons une étude globale de la qualité des données à travers leur disponibilité, la comparaison aux comportements attendus par parties d’ouvrages et la comparaison avec les données thermiques disponibles. Numéro de notice : A2021-463 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : sans Date de publication en ligne : 01/06/2021 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97945
in XYZ > n° 167 (juin 2021) . - pp 39 - 44[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 112-2021021 RAB Revue Centre de documentation En réserve L003 Disponible Identification of common points in hybrid geodetic networks to determine vertical movements of the Earth’s crust / Kamil Kowalczyk in Journal of applied geodesy, vol 15 n° 2 (April 2021)PermalinkPermalinkVariations of precipitable water vapor using GNSS CORS in Thailand / Chokchai Trakolkul in Survey review, vol 53 n°376 (January 2021)PermalinkAn assessment of wide-lane ambiguity resolution methods for multi-frequency multi-GNSS precise point positioning / Viet Duong in Survey review, vol 52 n° 374 (August 2020)PermalinkImproving GNSS-acoustic positioning by optimizing the ship’s track lines and observation combinations / Guanxu Chen in Journal of geodesy, vol 94 n° 6 (June 2020)PermalinkComparative analysis of different atmospheric surface pressure models and their impacts on daily ITRF2014 GNSS residual time series / Zhao Li in Journal of geodesy, vol 94 n°4 (April 2020)PermalinkEstimation and representation of regional atmospheric corrections for augmenting real-time single-frequency PPP / Peiyuan Zhou in GPS solutions, vol 24 n° 1 (January 2020)PermalinkPermalinkModelling of the timeseries of GNSS coordinates and their interaction with average magnitude earthquakes / Sanja Tucikesic in Geodetski vestnik, Vol 63 n° 4 (December 2019)PermalinkGNSS metadata and data validation in the EUREF Permanent Network / Carine Bruyninx in GPS solutions, vol 23 n° 4 (October 2019)Permalink