Centre dedocumentation
scientifique

The impact of second-order ionospheric delays on the ZWD estimation with GPS and BDS measurements / Shaocheng Zhang in GPS solutions, vol 24 n° 2 (April 2020)  

Public [article]  inGPS solutions > vol 24 n° 2 (April 2020) Titre : The impact of second-order ionospheric delays on the ZWD estimation with GPS and BDS measurements Type de document : Article/Communication Auteurs : Shaocheng Zhang, Auteur ; Lei Fang, Auteur ; Guangxing Wang, Auteur ; Wei Li, Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale [Termes descripteurs IGN] champ géomagnétique [Termes descripteurs IGN] décalage d'horloge [Termes descripteurs IGN] données BeiDou [Termes descripteurs IGN] données GPS [Termes descripteurs IGN] gradient d'ionosphère [Termes descripteurs IGN] méthode des moindres carrés [Termes descripteurs IGN] positionnement ponctuel précis [Termes descripteurs IGN] retard ionosphèrique [Termes descripteurs IGN] retard troposphérique zénithal [Termes descripteurs IGN] teneur verticale totale en électrons Résumé : (auteur) Since millimeter accuracy is required in many GNSS applications such as real-time zenith wet delay (ZWD) estimation, the higher-order ionospheric delays on GNSS signals are no longer negligible. We calculated the second-order ionospheric delays (I2) and analyzed the impact on the ZWD estimation with GPS-only and combined GPS/BDS observations. The undifferenced PPP model with fixed coordinates was used to estimate the ZWD and horizontal gradients. The method of blockwise sequential least squares was utilized to eliminate the receiver clock biases and compute the I2 impact on the ZWDs. The I2 delays on each GNSS satellite observations were calculated with the CODE final TEC map and the 12th generation of the international geomagnetic reference field (IGRF-12) model. The statistical results with the actual observation geometry show that the I2 delays can reach over 10 mm during the daytime, and the corresponding impact on the estimated ZWD can reach up to several millimeters. At station HKWS, the maximum I2 impact with GPS only reaches up to 3.1 mm and is still 2.4 mm when both GPS and BDS observations are used. The simulated I2 impact on the ZWD could reach several millimeters, even though the TEC and geomagnetic values were calculated from relatively moderate background models. Compared with the 5–10 mm precision of real-time ZWD estimation, the I2 delays must not be ignored, especially during high VTEC periods. Numéro de notice : A2020-082 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-020-0954-8 date de publication en ligne : 04/02/2020 En ligne : https://doi.org/10.1007/s10291-020-0954-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94651 [article]

Radial interpolation of GPS and leveling data of ground deformation in a resurgent caldera: application to Campi Flegrei (Italy) / Andrea Bevilacqua in Journal of geodesy, vol 94 n°2 (February 2020)  

Public [article]  inJournal of geodesy > vol 94 n°2 (February 2020) Titre : Radial interpolation of GPS and leveling data of ground deformation in a resurgent caldera: application to Campi Flegrei (Italy) Type de document : Article/Communication Auteurs : Andrea Bevilacqua, Auteur ; Augusto Neri, Auteur ; Prospero De Martino, Auteur ; et al., Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications [Termes descripteurs IGN] analyse diachronique [Termes descripteurs IGN] caldeira [Termes descripteurs IGN] Campanie (Italie) [Termes descripteurs IGN] déformation horizontale de la croute terrestre [Termes descripteurs IGN] déformation verticale de la croute terrestre [Termes descripteurs IGN] donnée de nivellement [Termes descripteurs IGN] données géodésiques [Termes descripteurs IGN] données GPS [Termes descripteurs IGN] fonction de base radiale [Termes descripteurs IGN] image radar moirée [Termes descripteurs IGN] interféromètrie par radar à antenne synthétique [Termes descripteurs IGN] interpolation [Termes descripteurs IGN] modèle de déformation tectonique [Termes descripteurs IGN] régression linéaire [Termes descripteurs IGN] réseau de nivellement [Termes descripteurs IGN] surveillance géologique [Termes descripteurs IGN] volcan Résumé : (auteur) This study presents a new method, called the Radial Interpolation Method, to interpolate data characterized by an approximately radial pattern around a relatively constrained central zone, such as the ground deformation patterns shown in many active volcanic areas. The method enables the fast production of short-term deformation maps on the base of spatially sparse ground deformation measurements and can provide uncertainty quantification on the interpolated values, fundamental for hazard assessment purposes and deformation source reconstruction. The presented approach is not dependent on a priori assumptions about the geometry, location and physical properties of the source, except for the requirement of a locally radial pattern, i.e., allowing multiple centers of symmetry. We test the new method on a synthetic point source example, and then, we apply the method to selected time intervals of real geodetic data collected at the Campi Flegrei caldera during the last 39 years, including examples of leveling, Geodetic Precise Traversing measurements and Global Positioning System. The maps of horizontal displacement, calculated inland, show maximum values lying along a semicircular annular region with a radius of about 2–3 km in size. This semi-annular area is marked by mesoscale structures such as faults, sand dikes and fractures. The maps of vertical displacement describe a linear relation between the maximum vertical uplift measured and the volume variation. The multiplicative factor in the linear relation is about 0.3 × 106 m3/cm if we estimate the proportion of the ΔV that is captured by the GPS network onland and we use this to estimate the full ΔV. In this case, the 95% confidence interval on K because of linear regression is ± 5%. Finally, we briefly discuss how the new method could be used for the production of short-term vent opening maps on the base of real-time geodetic measurements of the horizontal and vertical displacements. Numéro de notice : A2020-152 Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01355-x date de publication en ligne : 05/02/2020 En ligne : https://doi.org/10.1007/s00190-020-01355-x Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94785 [article]

Absolute field calibration for multi-GNSS receiver antennas at ETH Zurich / Daniel Willi in GPS solutions, vol 24 n° 1 (January 2020)  

Public [article]  inGPS solutions > vol 24 n° 1 (January 2020) Titre : Absolute field calibration for multi-GNSS receiver antennas at ETH Zurich Type de document : Article/Communication Auteurs : Daniel Willi, Auteur ; Simon Lutz, Auteur ; Elmar Brockmann, Auteur ; Markus Rothacher, Auteur Année de publication : 2020 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale [Termes descripteurs IGN] antenne Galileo [Termes descripteurs IGN] antenne GNSS [Termes descripteurs IGN] antenne GPS [Termes descripteurs IGN] centre de phase [Termes descripteurs IGN] données Galileo [Termes descripteurs IGN] données GPS [Termes descripteurs IGN] données multicapteurs [Termes descripteurs IGN] étalonnage au sol [Termes descripteurs IGN] étalonnage d'instrument [Termes descripteurs IGN] étalonnage des données [Termes descripteurs IGN] international GPS service for geodynamics [Termes descripteurs IGN] mesurage de phase [Termes descripteurs IGN] récepteur GNSS [Termes descripteurs IGN] robot [Termes descripteurs IGN] signal GNSS [Termes descripteurs IGN] Zurich (Suisse) Résumé : (Auteur) ETH Zurich developed an absolute GNSS antenna calibration system based on measurements taken in the field. An industrial robot is used to rotate and tilt the antenna to be calibrated. This procedure ensures good coverage of the antenna hemisphere and reduces systematic errors. The calibration system at ETH Zurich is validated by a direct comparison of the obtained calibrations with calibrations from the anechoic chamber method (University of Bonn) and from another absolute field calibration method (Geo++® GmbH). Calibrations by ETH Zurich agree on the sub-millimeter level with both reference calibrations. A second validation was conducted using real measurements on short baselines. Data were acquired on four stations in direct vicinity and processed using different phase center correction models. The experiment shows that individual corrections of ETH Zurich reduce the residuals in the coordinate domain when compared to type-mean calibrations of the International GNSS Service (IGS). However, residual biases between GPS and Galileo coordinates remain. These biases are efficiently reduced when using the new type-mean calibrations from the IGS that include calibration values for all GNSS, including Galileo. The ETH Zurich calibration system is proven to deliver meaningful calibrations that agree with other calibrations on the millimeter level in the azimuth and elevation domain. The field validation shows evidence that the consistency of the Galileo and GPS calibration should be further enhanced by performing a combined GPS and Galileo analysis, which is not yet implemented. Numéro de notice : A2020-020 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-019-0941-0 date de publication en ligne : 19/12/2019 En ligne : https://doi.org/10.1007/s10291-019-0941-0 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94460 [article]

Complex deformation at shallow depth during the 30 October 2016 Mw6.5 Norcia earthquake: interferencebetween tectonic and gravity processes? / Arthur Delorme in Tectonics, Inconnu (2020)    

Public [article]  contenu dans HAL Hyper articles en ligne / Centre pour la Communication Scientifique Directe CCSD (2000)   inTectonics > Inconnu (2020) Titre : Complex deformation at shallow depth during the 30 October 2016 Mw6.5 Norcia earthquake: interferencebetween tectonic and gravity processes? Type de document : Article/Communication Auteurs : Arthur Delorme, Auteur ; Raphaël Grandin, Auteur ; Yann Klinger, Auteur ; Marc Pierrot-Deseilligny , Auteur ; Nathalie Feuillet, Auteur ; Eric Jacques, Auteur ; Ewelina Rupnik , Auteur ; Yu Morishita, Auteur Année de publication : 2020 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte [Termes descripteurs IGN] analyse comparative [Termes descripteurs IGN] compensation locale par faisceaux [Termes descripteurs IGN] corrélation d'images [Termes descripteurs IGN] déformation de la croute terrestre [Termes descripteurs IGN] données GPS [Termes descripteurs IGN] données spatiotemporelles [Termes descripteurs IGN] effondrement de terrain [Termes descripteurs IGN] géodésie physique [Termes descripteurs IGN] image à résolution submétrique [Termes descripteurs IGN] image ALOS [Termes descripteurs IGN] image Pléiades-HR [Termes descripteurs IGN] interféromètrie par radar à antenne synthétique [Termes descripteurs IGN] Italie [Termes descripteurs IGN] MicMac [Termes descripteurs IGN] modèle par fonctions rationnelles [Termes descripteurs IGN] séisme Résumé : (Auteur) The relation between slip at the near surface and at depth during earthquakes is still not fully resolved at the moment. This deficiency leads to large uncertainties in the evaluation of the magnitude of past earthquakes based on surfaceobservations, which is the only accessible evidence for such events. A better knowledge of the way slip distributes over distinct rupture strands within the first few kilometers from the surface would contribute greatly to reduce these uncertainties. The 30 October 2016 Mw6.5 Norcia earthquake has been captured by a variety of geodetic techniques, which provide access to the slip distribution both at depth and at the ground surface, with an unprecedented level of detail for a normal-faulting earthquake. Wefirst present coseismic surface offset measurements from correlation of optical satellite imagesof sub-metric resolution, which are compared to field observations made shortly after the earthquake. Based on a joint inversion of optical data together withInSAR and GPS data, we then propose a rupture model that explains the observations both at far-field and near-field scales. Finally we explore different rupture geometriesat shallow depth, in an attempt to better explain the near-field deformation (i.e. within the first hundreds of meters around the fault)observed at the surface. Despite the fact that the solution is not unique, several lines of evidence suggest that gravity processes could be locally involved, which interfere with the dominant tectonic processes. Numéro de notice : A2020-039 Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2019TC005596 date de publication en ligne : 03/01/2020 En ligne : https://dx.doi.org/10.1029/2019TC005596 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94501 [article]

Documents numériques

peut être téléchargé Complex deformation at shallow depth... - pdf auteur Adobe Acrobat PDF

Subsidence is determined in the heart of the Central Valley using Post Processed Static and Precise Point Positioning techniques / Y. Facio in Journal of applied geodesy, vol 14 n° 1 (January 2020)  

Public [article]  inJournal of applied geodesy > vol 14 n° 1 (January 2020) . - pp 113 - 118 Titre : Subsidence is determined in the heart of the Central Valley using Post Processed Static and Precise Point Positioning techniques Type de document : Article/Communication Auteurs : Y. Facio, Auteur ; M Mustafa Berber, Auteur Année de publication : 2020 Article en page(s) : pp 113 - 118 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Nivellement [Termes descripteurs IGN] analyse comparative [Termes descripteurs IGN] Californie (Etats-Unis) [Termes descripteurs IGN] décalage d'horloge [Termes descripteurs IGN] déformation de la croute terrestre [Termes descripteurs IGN] données GPS [Termes descripteurs IGN] format RINEX [Termes descripteurs IGN] mesurage de phase [Termes descripteurs IGN] positionnement ponctuel précis [Termes descripteurs IGN] post-traitement GNSS [Termes descripteurs IGN] station de référence [Termes descripteurs IGN] subsidence Résumé : (auteur) Post Processed Static (PPS) and Precise Point Positioning (PPP) techniques are not new; however, they have been refined over the decades. As such, today these techniques are offered online via GPS (Global Positioning System) data processing services. In this study, one Post Processed Static (OPUS) and one Precise Point Positioning (CSRS-PPP) technique is used to process 24 h GPS data for a CORS (Continuously Operating Reference Stations) station (P565) duration of year 2016. By analyzing the results sent by these two online services, subsidence is determined for the location of CORS station, P565, as 3–4 cm for the entire year of 2016. In addition, precision of these two techniques is determined as ∼2 cm. Accuracy of PPS and PPP results is 0.46 cm and 1.21 cm, respectively. Additionally, these two techniques are compared and variations between them is determined as 2.5 cm. Numéro de notice : A2020-042 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2019-0043 date de publication en ligne : 07/12/2019 En ligne : https://doi.org/10.1515/jag-2019-0043 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94513 [article]

Decomposition of geodetic time series: A combined simulated annealing algorithm and Kalman filter approach / Feng Ming in Advances in space research, vol 64 n°5 (1 September 2019)  

Permalink

The Parallel SBAS approach for Sentinel-1 interferometric wide swath deformation time-series generation: algorithm description and products quality assessment / Michele Manunta in IEEE Transactions on geoscience and remote sensing, vol 57 n° 9 (September 2019)  

Permalink

Discovery of new code interference phenomenon in GPS observables / Connor D. Flynn in GPS solutions, vol 23 n° 3 (July 2019)  

Permalink

Geometric and statistical interpretation of correlation between fault tests in integrated GPS/INS systems / Ali Almagbile in Journal of applied geodesy, vol 13 n° 3 (July 2019)  

Permalink

Processing of GNSS constellations and ground station networks using the raw observation approach / Sebastian Strasser in Journal of geodesy, vol 93 n°7 (July 2019)  

Permalink

Sensitivity of GPS tropospheric estimates to mesoscale convective systems in West Africa / Samuel Nahmani in Atmospheric chemistry and physics, vol 19 n° 14 (juillet 2019)    

Permalink

Low-complexity online correction and calibration of pedestrian dead reckoning using map matching and GPS / Fabian Hölzke in Geo-spatial Information Science, vol 22 n° 2 (June 2019)  

Permalink

Ability of GPS PPP in 2D deformation analysis with respect to GPS network solution / C. Aydin in Survey review, vol 51 n° 366 (May 2019)  

Permalink

Analyse spatiotemporelle des tournées de livraison d’une entreprise de livraison à domicile / Khaled Belhassine in Revue internationale de géomatique, vol 29 n° 2 (avril - juin 2019)  

Permalink

Le réseau GPS permanent (RGP) de l'IGN / Sébastien Saur in Géomètre, n° 2168 (avril 2019)

Permalink