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Termes IGN > sciences naturelles > sciences de la Terre et de l'univers > géosciences > géophysique interne > géodésie > géodésie spatiale > interférométrie > interférométrie à très grande base
interférométrie à très grande baseSynonyme(s)vlbi Interférométrie à très longue base |
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The importance of co-located VLBI Intensive stations and GNSS receivers / Christopher Dieck in Journal of geodesy, vol 97 n° 3 (March 2023)
[article]
Titre : The importance of co-located VLBI Intensive stations and GNSS receivers Type de document : Article/Communication Auteurs : Christopher Dieck, Auteur ; Megan C. Johnson, Auteur ; Daniel S. MacMillan, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 21 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Hawaii (Etats-Unis)
[Termes IGN] interférométrie à très grande base
[Termes IGN] positionnement par ITGB
[Termes IGN] rapport signal sur bruit
[Termes IGN] récepteur GNSS
[Termes IGN] station GNSS
[Termes IGN] station VLBI
[Termes IGN] temps universel coordonnéRésumé : (auteur) Frequent, low-latency measurements of the Earth’s rotation phase, expressed as UT1−UTC critically support the current estimate and short-term prediction of this highly variable Earth orientation parameter (EOP). Very long baseline interferometry (VLBI) Intensive sessions provide the required data. However, the Intensive UT1−
UTC measurement accuracy depends on the accuracy of numerous models, including the VLBI station position. Intensives observed with the Maunakea (Mk) and Pie Town (Pt) stations of the Very Long Baseline Array (VLBA) illustrate how a geologic event (i.e., the Mw 6.9 Hawai‘i Earthquake of May 4th, 2018) can cause a station displacement and an associated offset in the values of UT1−UTC measured by that baseline, rendering the data from the series useless until it is corrected. Using the nonparametric Nadaraya–Watson estimator to smooth the measured UT1−UTC values before and after the earthquake, we calculate the offset in the measurement to be 75.7 ± 4.6 μs. Analysis of the sensitivity of the Mk-Pt baseline’s UT1−UTC measurement to station position changes shows that the measured offset is consistent with the 67.2 ± 5.9 μs expected offset based on the 12.4 ± 0.6 mm total coseismic displacement of the Maunakea VLBA station determined from the displacement of the co-located global navigation satellite system (GNSS) station. GNSS station position information is known with a latency on the order of tens of hours and thus can be used to correct the a priori position model of a co-located VLBI station such that it can continue to provide accurate measurements of the critical EOP UT1−UTC as part of Intensive sessions. In the absence of a co-located GNSS receiver, the VLBI station position model would likely not be updated for several months, and a near real-time correction would not be possible. This contrast highlights the benefit of co-located GNSS and VLBI stations in support of the monitoring of UT1−UTC with single-baseline Intensives.Numéro de notice : A2023-133 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-022-01690-1 Date de publication en ligne : 03/03/2023 En ligne : https://doi.org/10.1007/s00190-022-01690-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102678
in Journal of geodesy > vol 97 n° 3 (March 2023) . - n° 21[article]Evaluation of the GSRM2.1 and the NUVEL1-A values in Europe using SLR and VLBI based geodetic velocity fields / Mina Rahmani in Survey review, vol 54 n° 385 (July 2022)
[article]
Titre : Evaluation of the GSRM2.1 and the NUVEL1-A values in Europe using SLR and VLBI based geodetic velocity fields Type de document : Article/Communication Auteurs : Mina Rahmani, Auteur ; Vahab Nafisi, Auteur ; Sigrid Böhm, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : pp 349 - 362 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] champ de vitesse
[Termes IGN] cohérence des données
[Termes IGN] données ITGB
[Termes IGN] données TLS (télémétrie)
[Termes IGN] magnitude
[Termes IGN] tectonique des plaquesRésumé : (auteur) The NUVEL1-A is one of the old and popular plate tectonic models. While the NUVEL1-A is a geological-based model, recently a model has been proposed (GSRM2.1 model) which is based on the results of space geodetic techniques. In this work, we investigate the consistency of these models with the VLBI and SLR results in Europe. Direction and magnitude of the horizontal motion from NUVEL-1A and GSRM2.1 models are compared with corresponding values from both geodetic techniques. This comparison provides valuable deductions such as: (1) The values of geodetic-based model (GSRM2.1) show better agreement with SLR and VLBI results (2) In each comparison between geodetic results and modelled values, direction divergence is larger than magnitude difference. Numéro de notice : A2022-536 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2021.1943633 Date de publication en ligne : 25/06/2021 En ligne : https://doi.org/10.1080/00396265.2021.1943633 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101092
in Survey review > vol 54 n° 385 (July 2022) . - pp 349 - 362[article]Baseline-dependent clock offsets in VLBI data analysis / Hana Krásná in Journal of geodesy, vol 95 n° 12 (December 2021)
[article]
Titre : Baseline-dependent clock offsets in VLBI data analysis Type de document : Article/Communication Auteurs : Hana Krásná, Auteur ; Frédéric Jaron, Auteur ; Jacob Gruber, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 126 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] bande S
[Termes IGN] décalage d'horloge
[Termes IGN] données ITGB
[Termes IGN] horloge atomique
[Termes IGN] interférométrie à très grande base
[Termes IGN] ligne de base
[Termes IGN] paramètres d'orientation de la Terre
[Termes IGN] retard ionosphèriqueRésumé : (auteur) The primary goal of the geodetic Very Long Baseline Interferometry (VLBI) technique is to provide highly accurate terrestrial and celestial reference frames as well as Earth orientation parameters. In compliance with the concept of VLBI, additional parameters reflecting relative offsets and variations of the atomic clocks of the radio telescopes have to be estimated. In addition, reality shows that in many cases significant offsets appear in the observed group delays for individual baselines which have to be compensated for by estimating so-called baseline-dependent clock offsets (BCOs). For the first time, we systematically investigate the impact of BCOs to stress their importance for all kinds of VLBI data analyses. For our investigations, we concentrate on analyzing data from both legacy networks of the CONT17 campaign. Various aspects of BCOs including their impact on the estimates of geodetically important parameters, such as station coordinates and Earth orientation parameters, are investigated. In addition, some of the theory behind the BCO determination, e.g., the impact of changing the reference clock in the observing network on the BCO estimate is introduced together with the relationship between BCOs and triangle delay closures. In conclusion, missing channels, and here in particular at S band, affecting the ionospheric delay calibration, are identified to be the dominant cause for the occurrence of significant BCOs in VLBI data analysis. Numéro de notice : A2021-815 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-021-01579-5 Date de publication en ligne : 01/11/2021 En ligne : https://doi.org/10.1007/s00190-021-01579-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98896
in Journal of geodesy > vol 95 n° 12 (December 2021) . - n° 126[article]Observable quality assessment of broadband very long baseline interferometry system / Ming H. Xu in Journal of geodesy, vol 95 n° 5 (May 2021)
[article]
Titre : Observable quality assessment of broadband very long baseline interferometry system Type de document : Article/Communication Auteurs : Ming H. Xu, Auteur ; James M. Anderson, Auteur ; Robert Heinkelmann, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 51 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] données VGOS
[Termes IGN] erreur moyenne quadratique
[Termes IGN] interférométrie à très grande base
[Termes IGN] pondération
[Termes IGN] propagation ionosphérique
[Termes IGN] retard ionosphèrique
[Termes IGN] teneur totale en électronsRésumé : (auteur) The next-generation, broadband geodetic very long baseline interferometry system, named VGOS, is developing its global network, and VGOS networks with a small size of 3–7 stations have already made broadband observations from 2017 to 2019. We made quality assessments for two kinds of observables in the 21 VGOS sessions currently available: group delay and differential total electron content (δTEC). Our study reveals that the random measurement noise of VGOS group delays is at the level of less than 2 ps (1ps=10−12 s), while the contributions from systematic error sources, mainly source structure related, are at the level of 20 ps. Due to the significant improvement in measurement noise, source structure effects with relatively small magnitudes that are not overwhelming in the S/X VLBI system, for instance 10 ps, are clearly visible in VGOS observations. Another critical error source in VGOS observations is discrete delay jumps, for instance, a systematic offset of about 310 ps or integer multiples of that. The predominant causative factor is found to be related to source structure. The measurement noise level of δTEC observables is about 0.07 TECU, but the systematic effects are five times larger than that. A strong correlation between group delay and δTEC observables is discovered with a trend of 40 ps/TECU for observations with large structure effects; there is a second trend in the range 60–70 ps/TECU when the measurement noise is dominant. Numéro de notice : A2021-346 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-021-01496-7 Date de publication en ligne : 13/04/2021 En ligne : https://doi.org/10.1007/s00190-021-01496-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97590
in Journal of geodesy > vol 95 n° 5 (May 2021) . - n° 51[article]
Titre : Stochastic models for geodesy and geoinformation science Type de document : Monographie Auteurs : Frank Neitzel, Éditeur scientifique Editeur : Bâle [Suisse] : Multidisciplinary Digital Publishing Institute MDPI Année de publication : 2021 Importance : 200 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-3-03943-982-9 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] B-Spline
[Termes IGN] covariance
[Termes IGN] erreur de phase
[Termes IGN] incertitude de mesurage
[Termes IGN] interférométrie à très grande base
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle stochastique
[Termes IGN] phase GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] réseau géodésique
[Termes IGN] télémétrie laser aéroportéRésumé : (éditeur) In geodesy and geoinformation science, as well as in many other technical disciplines, it is often not possible to directly determine the desired target quantities. Therefore, the unknown parameters must be linked with the measured values by a mathematical model which consists of the functional and the stochastic models. The functional model describes the geometrical–physical relationship between the measurements and the unknown parameters. This relationship is sufficiently well known for most applications. With regard to the stochastic model, two problem domains of fundamental importance arise: 1. How can stochastic models be set up as realistically as possible for the various geodetic observation methods and sensor systems? 2. How can the stochastic information be adequately considered in appropriate least squares adjustment models? Further questions include the interpretation of the stochastic properties of the computed target values with regard to precision and reliability and the use of the results for the detection of outliers in the input data (measurements). In this Special Issue, current research results on these general questions are presented in ten peer-reviewed articles. The basic findings can be applied to all technical scientific fields where measurements are used for the determination of parameters to describe geometric or physical phenomena. Note de contenu : 1- Total least-squares collocation: An optimal estimation technique for the EIV-model with prior information
2- Weighted Total Least Squares (WTLS) Solutions for straight line fitting to 3D point data
3- Stochastic properties of confidence ellipsoids after least squares adjustment, derived from GUM analysis and Monte Carlo simulations
4- Mean shift versus variance inflation approach for outlier detection—A comparative study
5- A generic approach to covariance function estimation using ARMA-models
6- Evaluation of VLBI observations with sensitivity and robustness analyses
7- Variance reduction of sequential Monte Carlo approach for GNSS phase bias estimation
8- Automatic calibration of process noise matrix and measurement noise covariance for multi-GNSS precise point positioning
9- Elementary error model applied to terrestrial laser scanning measurements: Study case arch Dam Kops
10- On estimating the hurst parameter from least-squares residuals. Case study: Correlated terrestrial laser scanner range noiseNuméro de notice : 28459 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Recueil / ouvrage collectif DOI : 10.3390/books978-3-03943-982-9 En ligne : http://dx.doi.org/10.3390/books978-3-03943-982-9 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99044 Benefits of non-tidal loading applied at distinct levels in VLBI analysis / Matthias Glomsda in Journal of geodesy, vol 94 n° 9 (September 2020)PermalinkGipsyX/RTGx, a new tool set for space geodetic operations and research / Willy I. Bertiger in Advances in space research, vol 66 n° 3 (1 August 2020)PermalinkGeodetic VLBI for precise orbit determination of Earth satellites: a simulation study / Grzegorz Klopotek in Journal of geodesy, vol 94 n° 6 (June 2020)PermalinkCombinatorial optimization applied to VLBI scheduling / A. Corbin in Journal of geodesy, vol 94 n°2 (February 2020)PermalinkPermalinkSystematic errors in SLR data and their impact on the ILRS products / Vincenza Luceri in Journal of geodesy, vol 93 n°11 (November 2019)PermalinkTroposphere delay modeling with horizontal gradients for satellite laser ranging / Mateusz Drożdżewski in Journal of geodesy, vol 93 n°10 (October 2019)PermalinkModeling the VLBI delay for Earth satellites / Frédéric Jaron in Journal of geodesy, vol 93 n°7 (July 2019)PermalinkLeast-squares cross-wavelet analysis and its applications in geophysical time series / Ebrahim Ghaderpour in Journal of geodesy, vol 92 n° 10 (October 2018)PermalinkGeodetic VLBI with an artificial radio source on the Moon : a simulation study / Grzegorz Klopotek in Journal of geodesy, vol 92 n° 5 (May 2018)PermalinkPermalinkBasic Earth's Parameters as estimated from VLBI observations / Ping Zhu in Geodesy and Geodynamics, vol 8 n° 6 (November 2017)PermalinkApplication of ray-traced tropospheric slant delays to geodetic VLBI analysis / Armin Hofmeister in Journal of geodesy, vol 91 n° 8 (August 2017)PermalinkA global terrestrial reference frame from simulated VLBI and SLR data in view of GGOS / Susanne Glaser in Journal of geodesy, vol 91 n° 7 (July 2017)PermalinkImproving the modeling of the atmospheric delay in the data analysis of the Intensive VLBI sessions and the impact on the UT1 estimates / Tobias Nilsson in Journal of geodesy, vol 91 n° 7 (July 2017)PermalinkThe extension of the parametrization of the radio source coordinates in geodetic VLBI and its impact on the time series analysis / Maria Karbon in Journal of geodesy, vol 91 n° 7 (July 2017)PermalinkOn the consistency of the current conventional EOP series and the celestial and terrestrial reference frames / Santiago Belda in Journal of geodesy, vol 91 n° 2 (February 2017)PermalinkPermalinkPermalinkPermalinkComplex demodulation in monitoring earth rotation by VLBI: testing the algorithm by analysis of long periodic EOP components / Agata Wielgosz in Artificial satellites, vol 51 n° 4 (December 2016)PermalinkDetermination of a terrestrial reference frame via Kalman filtering of very long baseline interferometry data / Benedikt Soja in Journal of geodesy, vol 90 n° 12 (December 2016)PermalinkTesting impact of the strategy of VLBI data analysis on the estimation of Earth Orientation Parameters and station coordinates / Agata Wielgosz in Reports on geodesy and geoinformatics, vol 101 (June 2016)PermalinkCaractérisation des signaux et des bruits des séries temporelles du géocentre et des paramètres de rotation de la Terre (EOP) / Bachir Gourine in Bulletin des sciences géographiques, n° 30 (2015 - 2016)PermalinkPermalinkThe Fresnel–Fizeau effect and the atmospheric time delay in geodetic VLBI / S. M. Kopeikin in Journal of geodesy, vol 89 n° 8 (August 2015)PermalinkDetermination of the local tie vector between the VLBI and GNSS reference points at Onsala using GPS measurements / Tong Ning in Journal of geodesy, vol 89 n° 7 (July 2015)PermalinkPermalinkContinental hydrology loading observed by VLBI measurements / David Eriksson in Journal of geodesy, vol 88 n° 7 (July 2014)PermalinkEarth orientation parameters estimated from VLBI during the CONT11 campaign / Tobias Nilsson in Journal of geodesy, vol 88 n° 5 (May 2014)PermalinkNew VLBI2010 scheduling strategies and implications on the terrestrial reference frames / Jing Sun in Journal of geodesy, vol 88 n° 5 (May 2014)PermalinkPermalinkPermalinkPermalinkNon-linear station motions in epoch and multi-year reference frames / Mathis Blossfeld in Journal of geodesy, vol 88 n° 1 (January 2014)PermalinkQuantifying the correlation between the MEI and LOD variations by decomposing LOD with singular spectrum analysis / Karine Le Bail (2014)PermalinkRecherche des sous-réseaux d’antennes VLBI et de radio‐sources extra‐galactiques par algorithmes génétiques / Serge Nyoka (2014)PermalinkTroposphere delays from space geodetic techniques, water vapor radiometers, and numerical weather models over a series of continuous VLBI campaigns / Kamil Teke in Journal of geodesy, vol 87 n° 10-12 (October - December 2013)PermalinkAutomated and continual determination of radio telescope reference points with sub-mm accuracy: results from a campaign at the Onsala Space Observatory / Michael Lösler in Journal of geodesy, vol 87 n° 8 (August 2013)PermalinkImpact of seasonal station motions on VLBI UT1 intensives results / Zinovy Malkin in Journal of geodesy, vol 87 n° 6 (June 2013)PermalinkEarth System Mass Transport Mission (e.motion): A Concept for Future Earth Gravity Field Measurements from Space / Isabelle Panet in Surveys in Geophysics, vol 34 n° 2 (March 2013)PermalinkGeodetic reference frames : 40 years of technological progress and of international cooperation : 1970-2010 / Claude Boucher (2013)PermalinkPermalinkPermalinkEffects on the geodetic-VLBI observables due to polarization leakage in the receivers / Alessandra Roy (2012)PermalinkPermalinkRobust determination of station positions and Earth orientation parameters by VLBI intra-technique combination / S. Böckmann (2012)PermalinkPermalinkvol 85 n° 7 - July 2011 - CONT08 -continuous geodetic VLBI campaign 2008 August 12-26 2008 (Bulletin de Journal of geodesy) / Axel NothnagelPermalinkHigh-resolution atmospheric angular momentum functions related to Earth rotation parameters during CONT08 / Daniel Gambis in Journal of geodesy, vol 85 n° 7 (July 2011)PermalinkMulti-technique comparison of troposphere zenith delays and gradients during CONT08 / Kamil Teke in Journal of geodesy, vol 85 n° 7 (July 2011)PermalinkLe repère céleste de références : définition et amélioration / Anonyme in Géomatique expert, n° 81 (01/07/2011)PermalinkVLBI-derived troposphere parameters during CONT08 / Robert Heinkelmann in Journal of geodesy, vol 85 n° 7 (July 2011)PermalinkCombinaison multi-techniques au niveau des observations : Quels avantages ? / Arnaud Pollet in Bulletin d'information scientifique et technique de l'IGN, n° 77 (avril 2011)PermalinkPermalinkPermalinkPermalinkPermalinkThe crustal dynamics data information system: a resource to support scientific analysis using space geodesy / Carey E. Noll in Advances in space research, vol 45 n° 12 (15/06/2010)PermalinkAsymmetric tropospheric delays from numerical weather models for UT1 determination from VLBI Intensive sessions on the baseline Wettzell–Tsukuba / Johannes Böhm in Journal of geodesy, vol 84 n° 5 (May 2010)PermalinkPermalinkSpace-time reference systems for monitoring global change and for precise navigation / Axel Nothnagel (2010)PermalinkLocal effects of redundant terrestrial and GPS-based tie vectors in ITRF-like combinations / Claudio Abbondanza in Journal of geodesy, vol 83 n° 11 (November 2009)PermalinkLocal effects of redundant terrestrial and GPS-based tie vectors in ITRF-like combinations / Claudio Abbondanza in Journal of geodesy, vol 83 n° 11 (November 2009)PermalinkPermalinkPermalinkThe impact of errors in polar motion and nutation on UT1 determinations from VLBI Intensive observations / Axel Nothnagel in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkOn the accuracy assessment of celestial reference frame realizations / Z. Malkin in Journal of geodesy, vol 82 n° 6 (June 2008)PermalinkPermalinkPermalinkLocal ties, VLBI-GPS eccentricities and combination of geodetic reference frames / Claudio Abbondanza (2008)PermalinkComparison of very long baseline interferometry, GPS, and satellite laser ranging height residuals from ITRF2005 using spectral and correlation methods / Xavier Collilieux in Journal of geophysical research : Solid Earth, vol 112 n° B12 (December 2007)PermalinkITRF2005: A new release of the International Terrestrial Reference Frame based on time series of station positions and Earth Orientation Parameters / Zuheir Altamimi in Journal of geophysical research : Solid Earth, vol 112 n° 9 (September 2007)PermalinkCombined Earth orientation parameters based on homogeneous and continuous VLBI and GPS data / Daniela Thaller in Journal of geodesy, vol 81 n° 6-8 (June - August 2007)PermalinkIndirect approach to invariant point determination for SLR and VLBI systems: an assessment / John Dawson in Journal of geodesy, vol 81 n° 6-8 (June - August 2007)PermalinkThe impact of radio source structure on European geodetic VLBI measurements / V. Tornatore in Journal of geodesy, vol 81 n° 6-8 (June - August 2007)PermalinkA comparison of GPS, VLBI and model estimates of ocean tide loading displacements / I.D. Thomas in Journal of geodesy, vol 81 n° 5 (May 2007)PermalinkPermalinkProccedings of the 18th European VLBI for geodesy and astrometry working meeting, Vienna, 12-13 April 2007 / Johannes Böhm (2007)PermalinkSpace geodetic techniques and the canadian spatial reference system evolution, status and possibilities / Pierre Héroux in Geomatica, vol 60 n° 2 (June 2006)PermalinkPermalinkPermalinkPermalinkPermalinkIs there utility in rigorous combinations of VLBI and GPS Earth orientation parameters? / Jim Ray in Journal of geodesy, vol 79 n° 9 (December 2005)PermalinkEvaluation of co-location ties relating the VLBI and GPS reference frames / Jim Ray in Journal of geodesy, vol 79 n° 4-5 (July 2005)PermalinkPermalinkPermalinkPermalinkLa géodésie française et mondiale : une évolution considérable en 25 ans / Michel Kasser in XYZ, n° 100 (septembre - novembre 2004)PermalinkDas stochastische Modell bei der VLBI-Auswertung / V. Tesmer (2004)PermalinkEin eingebettetes ExpertSystem zur Automatisierung der VLBI-Auswertung / W. Schwegmann (2004)PermalinkInternational VLBI Service for Geodesy and Astrometry 2003 annual report / Nancy R. Vandenberg (2004)PermalinkPermalinkPermalink