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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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Complex 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)
[article]
Titre : Complex demodulation in monitoring earth rotation by VLBI: testing the algorithm by analysis of long periodic EOP components Type de document : Article/Communication Auteurs : Agata Wielgosz, Auteur Année de publication : 2016 Article en page(s) : pp 135 – 147 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] interférométrie à très grande base
[Termes IGN] modulation du signal
[Termes IGN] orientation de la Terre
[Termes IGN] rotation de la Terre
[Termes IGN] série temporelleRésumé : (auteur) The complex demodulation (CD) algorithm is an efficient tool for extracting the diurnal and subdiurnal components of Earth rotation from the routine VLBI observations (Brzeziński, 2012). This algorithm was implemented by Böhm et al (2012b) into a dedicated version of the VLBI analysis software VieVs. The authors processed around 3700 geodetic 24-hour observing sessions in 1984.0-2010.5 and estimated simultaneously the time series of the long period components as well as diurnal, semidiurnal, terdiurnal and quarterdiurnal components of polar motion (PM) and universal time UT1. This paper describes the tests of the CD algorithm by checking consistency of the low frequency components of PM and UT1 estimated by VieVS CD and those from the IERS and IVS combined solutions. Moreover, the retrograde diurnal component of PM demodulated from VLBI observations has been compared to the celestial pole offsets series included in the IERS and IVS solutions. We found for all three components a good agreement of the results based on the CD approach and those based on the standard parameterization recommended by the IERS Conventions (IERS, 2010) and applied by the IERS and IVS. We conclude that an application of the CD parameterization in VLBI data analysis does not change those components of EOP which are included in the standard adjustment, while enabling simultaneous estimation of the high frequency components from the routine VLBI observations. Moreover, we deem that the CD algorithm can also be implemented in analysis of other space geodetic observations, like GNSS or SLR, enabling retrieval of subdiurnal signals in EOP from the past data. Numéro de notice : A2016-976 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/arsa-2016-0012 En ligne : https://doi.org/10.1515/arsa-2016-0012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83687
in Artificial satellites > vol 51 n° 4 (December 2016) . - pp 135 – 147[article]Determination 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)
[article]
Titre : Determination of a terrestrial reference frame via Kalman filtering of very long baseline interferometry data Type de document : Article/Communication Auteurs : Benedikt Soja, Auteur ; Tobias Nilsson, Auteur ; Kyriakos Balidakis, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 1311 - 1327 Note générale : Bibliographie ; Erratum : voir pdf Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] bruit (théorie du signal)
[Termes IGN] coordonnées géographiques
[Termes IGN] filtre de Kalman
[Termes IGN] image radar moirée
[Termes IGN] interférométrie à très grande base
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] modèle stochastique
[Termes IGN] station permanenteRésumé : (Auteur) Terrestrial reference frames (TRF), such as the ITRF2008, are primary products of geodesy. In this paper, we present TRF solutions based on Kalman filtering of very long baseline interferometry (VLBI) data, for which we estimate steady station coordinates over more than 30 years that are updated for every single VLBI session. By applying different levels of process noise, non-linear signals, such as seasonal and seismic effects, are taken into account. The corresponding stochastic model is derived site-dependent from geophysical loading deformation time series and is adapted during periods of post-seismic deformations. Our results demonstrate that the choice of stochastic process has a much smaller impact on the coordinate time series and velocities than the overall noise level. If process noise is applied, tests with and without additionally estimating seasonal signals indicate no difference between the resulting coordinate time series for periods when observational data are available. In a comparison with epoch reference frames, the Kalman filter solutions provide better short-term stability. Furthermore, we find out that the Kalman filter solutions are of similar quality when compared to a consistent least-squares solution, however, with the enhanced attribute of being easier to update as, for instance, in a post-earthquake period. Numéro de notice : A2016-804 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0924-7 En ligne : http://dx.doi.org/10.1007/s00190-016-0924-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82591
in Journal of geodesy > vol 90 n° 12 (December 2016) . - pp 1311 - 1327[article]Testing 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)
[article]
Titre : Testing impact of the strategy of VLBI data analysis on the estimation of Earth Orientation Parameters and station coordinates Type de document : Article/Communication Auteurs : Agata Wielgosz, Auteur ; Monika Tercjak, Auteur ; Alexander Brzezinski, Auteur Année de publication : 2016 Article en page(s) : pp 1 - 15 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] données ITGB
[Termes IGN] interférométrie à très grande base
[Termes IGN] paramètres d'orientation de la Terre
[Termes IGN] pondération
[Termes IGN] station permanenteRésumé : (Auteur) Very Long Baseline Interferometry (VLBI) is the only space geodetic technique capable to realise the Celestial Reference Frame and tie it with the Terrestrial Reference Frame. It is also the only technique, which measures all the Earth Orientation Parameters (EOP) on a regular basis, thus the role of VLBI in determination of the universal time, nutation and polar motion and station coordinates is invaluable. Although geodetic VLBI has been providing observations for more than 30 years, there are no clear guidelines how to deal with the stations or baselines having significantly bigger post-fit residuals than the other ones. In our work, we compare the common weighting strategy, using squared formal errors, with strategies involving exclusion or down-weighting of stations or baselines. For that purpose, we apply the Vienna VLBI Software VieVS with necessary additional procedures. In our analysis, we focus on statistical indicators that might be the criterion of excluding or down-weighting the inferior stations or baselines, as well as on the influence of adopted strategy on the EOP and station coordinates estimation. Our analysis shows that in about 99% of 24-hour VLBI sessions there is no need to exclude any data as the down-weighting procedure is sufficiently efficient. Although results presented here do not clearly indicate the best algorithm, they show strengths and weaknesses of the applied methods and point some limitations of automatic analysis of VLBI data. Moreover, it is also shown that the influence of the adopted weighting strategy is not always clearly reflected in the results of analysis. Numéro de notice : A2016-649 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/rgg-2016-0017 En ligne : http://dx.doi.org/10.1515/rgg-2016-0017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81867
in Reports on geodesy and geoinformatics > vol 101 (June 2016) . - pp 1 - 15[article]Caractérisation 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)
[article]
Titre : Caractérisation des signaux et des bruits des séries temporelles du géocentre et des paramètres de rotation de la Terre (EOP) Type de document : Article/Communication Auteurs : Bachir Gourine, Auteur Année de publication : 2016 Article en page(s) : pp 18 - 27 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse diachronique
[Termes IGN] bruit blanc
[Termes IGN] bruit rose
[Termes IGN] caractérisation
[Termes IGN] données ITGB
[Termes IGN] données TLS (télémétrie)
[Termes IGN] estimation statistique
[Termes IGN] géocentre
[Termes IGN] géodésie spatiale
[Termes IGN] mesurage de la fréquence
[Termes IGN] rotation de la Terre
[Termes IGN] série temporelle
[Termes IGN] signal DORIS
[Termes IGN] signal GNSS
[Termes IGN] traitement du signal
[Termes IGN] variance d'AllanRésumé : (auteur) Pour comprendre le comportement des paramètres qui contrôlent le système Terre, tels que les paramètres de rotation de la Terre (EOP) et le mouvement Géocentre, il est nécessaire de les mesurer et de les analyser. Les techniques de géodésie spatiale (SLR, VLBI, DORIS et GPS) fournissent avec précision les séries temporelles des observations de ces phénomènes. L'objectif de ce travail est de caractériser les signaux et les bruits des séries temporelles des EOP et du Géocentre obtenues à partir de différentes techniques spatiales. La méthodologie adoptée est basée sur l'estimation des signaux périodiques par l'analyse fréquentielle et l'évaluation du niveau et du type de bruits par la variance d'Allan. Les données utilisées concernent 13 ans (1993-2006) de séries journalières des EOP (mouvement du pôle et longueur du jour ; LOD) et de séries hebdomadaires des coordonnées résiduelles du Géocentre, référées par rapport à l'ITRF2000. Les résultats révèlent que les amplitudes estimées des signaux périodiques sont de l'ordre de quelques mm par technique. Le mouvement du Géocentre obtenu par la technique SLR est plus précis que les autres techniques et il est proche des modèles géodynamiques. Les variations des EOP sont bien estimées par les techniques VLBI et GPS au niveau millimétrique. L'analyse du bruit des variations du Géocentre et des EOP, montre la dominance d'un bruit blanc dans les solutions SLR et DORIS. Cependant, les solutions VLBI et GPS sont caractérisées par un bruit de scintillation avec un niveau millimétrique. Numéro de notice : A2016-463 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81466
in Bulletin des sciences géographiques > n° 30 (2015 - 2016) . - pp 18 - 27[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 253-2016011 SL Revue Centre de documentation Revues en salle Disponible
Titre : Co-location of geodetic observation techniques in space Type de document : Thèse/HDR Auteurs : Benjamin Männel, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2016 Autre Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 97 Importance : 200 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-43-7 Note générale : bibliographie
A thesis submitted to attain the degree of Doctor of Sciences of ETH Zurich (Eidg. Technische Hochschule Zürich)Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GPS
[Termes IGN] Bernese
[Termes IGN] centre de phase
[Termes IGN] co-positionnement
[Termes IGN] données GRACE
[Termes IGN] géocentre
[Termes IGN] interférométrie à très grande base
[Termes IGN] International Terrestrial Reference System
[Termes IGN] orbite basse
[Termes IGN] orbitographie
[Termes IGN] positionnement par GPS
[Termes IGN] poursuite de satellite
[Termes IGN] propagation ionosphérique
[Termes IGN] repère de référence
[Termes IGN] système international de référence célesteIndex. décimale : 30.60 Géodésie spatiale Résumé : (auteur) This thesis describes the combination of geodetic observation techniques on-board satellites. This socalled co-location in space provides a considerable potential regarding the improvements needed to realize a long-term accurate and stable terrestrial reference frame. The space ties (i.e., the offset vectors between the on-board sensors) introduces new geometrical connections between sensors of dfferent space geodetic techniques. This space ties can be provided easily to each fundamental site via space geodetic observations. Consequently, co-location in space allows to assess technique-specific error sources as systematic effects can be addressed either to a certain station or to a certain technique. Moreover, the additional introduced orbit dynamics improve the estimation of several geodetic parameters. Within this thesis the following core topics concerning co-location in space are discussed: orbit determination, the combination of ground and space GNSS observations, and VLBI Earth-orbiting satellite tracking. Highly accurate orbit determination is the prerequisite for a suitable co-location in space. Based on the Earth observation satellite missions GRACE, GOCE, and OSTM/Jason-2 orbit determination and the impact of modeling non gravitational perturbations is studied. The overall reached orbit accuracies are at the level of a few centimeters. The combination of ground and space-geodetic GNSS observations is studied based on the GPS observations derived by 53 ground stations and the four LEOs (low Earth orbiter). Adding one LEO to the ground-only processing decreases the formal errors of weekly geocenter estimates by around 20% which is eight times more than expected due to the increased number of observations. This shows the considerable potential of the combination of ground and LEO data. Comparing the derived geocenter time series against results from satellite laser ranging (SLR) shows a good agreement for annual amplitudes, whereas the annual phases shows considerable discrepancies in the x- and the z-component. Geocenter coordinates derived from surface load density coeficients estimated in a long-term solution show a better agreement to SLR solutions but without a significant impact of additional LEOs. Using the gravitational constraint GPS satellite antenna phase center offsets were estimated based on ground and LEO observations. The results show a significant benefit for the horizontal offsets as the introduced LEOs help to dissolve limiting correlations. Concerning single-frequency VLBI satellite tracking the L4R method is introduced to derive ionosphere delay corrections based on co-located GNSS observations. A 1 cm daily station coordinate repeatability is achieved in a single-frequency GNSS processing while introducing the L4R corrections. Differences to ionospheric delays derived from VLBI observations show also a good agreement. As VLBI satellite tracking is currently in an experimental stage Monte-Carlo simulations were performed for eight different satellite orbit types. For a GNSS constellation tracking, station coordinate repeatabilities are at the level of 0.7 and 1.2 cm for a regional and a global network, respectively. Station coordinate repeatabilities of around 1 cm were derived for simulated VLBI observation to a fictitious LEO with an altitude of 2000 km. The station coordinates estimated from simulated observations to E-GRIP and E-GRASP/Eratosthenes show larger uncertainties. Based on the results suggestions for future action items regarding co-location in space were formulated. The most important recommendations are, that the combination of ground- and space GNSS observations provides a considerable benefit for the determination of several parameters and that ionosphere delay corrections should be derived from co-located GNSS observations. Note de contenu : 1- Motivation and Introduction
2- Geodetic Observation Techniques in a Nutshell
3- Reference Systems and the Combination and Co-location of Space Geodetic Techniques
4- Investigations on GPS-based Precise Orbit Determination for Low Earth Orbiters
5- Investigations on the Combined Processing of Ground- and Space-based GPS Observations
6- Investigations on VLBI Satellite Tracking
7- Conclusions and OutlookNuméro de notice : 21987 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : PhD : Sciences : ETH Zurich : 2016 DOI : 10.3929/ethz-a-010811791 En ligne : https://www.research-collection.ethz.ch/handle/20.500.11850/125751 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91982 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 21987-01 30.70 Livre Centre de documentation Géodésie Disponible The 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)PermalinkPermalinkPermalinkSciences of geodesy, vol 2. Innovations and future developments / Guochang Xu (2013)Permalink