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Auteur Michael B. Heflin |
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Affiner la recherche Interroger des sources externesGipsyX/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)
Titre : GipsyX/RTGx, a new tool set for space geodetic operations and research Type de document : Article/Communication Auteurs : Willy I. Bertiger, Auteur ; Yoaz E. Bar-Sever, Auteur ; A. Dorsey, Auteur ; Bruce J. Haines, Auteur ; N.R. Harvey, Auteur ; Dan Hemberger, Auteur ; Michael B. Heflin, Auteur ; Wenwen Lu, Auteur ; Mark Miller, Auteur ; Angelyn Moore, Auteur ; Dave Murphy, Auteur ; Paul Ries, Auteur ; L.J. Romans, Auteur ; Aurore E. Sibois, Auteur ; Ant Sibthorpe, Auteur ; Bela Szilagyi, Auteur ; Michele Vallisneri, Auteur ; Pascal Willis Année de publication : 2020 Projets : 3-projet - voir note / Article en page(s) : pp 469 - 489 Note générale : bibliographie
The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] données DORIS
[Termes IGN] données GNSS
[Termes IGN] données ITGB
[Termes IGN] données TLS (télémétrie)
[Termes IGN] filtre de Kalman
[Termes IGN] horloge atomique
[Termes IGN] horloge du satellite
[Termes IGN] logiciel d'orbitographie
[Termes IGN] positionnement ponctuel précis
[Termes IGN] série temporelle
[Termes IGN] temps réel
[Termes IGN] traitement de données GNSSRésumé : (auteur) GipsyX/RTGx is the Jet Propulsion Laboratory’s (JPL) next generation software package for positioning, navigation, timing, and Earth science using measurements from three geodetic techniques: Global Navigation Satellite Systems (GNSS), Satellite Laser Ranging (SLR), and Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS); with Very Long Baseline Interferometry (VLBI) under development. The software facilitates combined estimation of geodetic and geophysical parameters using a Kalman filter approach on real or simulated data in both post-processing and in real-time. The estimated parameters include station coordinates and velocities, satellite orbits and clocks, Earth orientation, ionospheric and tropospheric delays. The software is also capable of full realization of a dynamic terrestrial reference through analysis and combination of time series of ground station coordinates.
Applying lessons learned from its predecessors, GIPSY-OASIS and Real Time GIPSY (RTG), GipsyX/RTGx was re-designed from the ground up to offer improved precision, accuracy, usability, and operational flexibility. We present some key aspects of its new architecture, and describe some of its major applications, including Real-time orbit determination and ephemeris predictions in the U.S. Air Force Next Generation GPS Operational Control Segment (OCX), as well as in JPL’s Global Differential GPS (GDGPS) System, supporting User Range Error (URE) of
5 cm RMS; precision post-processing GNSS orbit determination, including JPL’s contributions to the International GNSS Service (IGS) with URE in the 2 cm RMS range; Precise point positioning (PPP) with ambiguity resolution, both statically and kinematically, for geodetic applications with 2 mm horizontal, and 6.5 mm vertical repeatability for static positioning; Operational orbit and clock determination for Low Earth Orbiting (LEO) satellites, such as NASA’s Gravity Recovery and Climate Experiment (GRACE) mission with GRACE relative clock alignment at the 20 ps level; calibration of radio occultation data from LEO satellites for weather forecasting and climate studies; Satellite Laser Ranging (SLR) to GNSS and LEO satellites, DORIS-based and multi-technique orbit determination for LEO; production of terrestrial reference frames and Earth rotation parameters in support of JPL’s contribution to the International Terrestrial Reference Frame (ITRF).Numéro de notice : A2020-575 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : INFORMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2020.04.015 Date de publication en ligne : 22/04/2020 En ligne : https://doi.org/10.1016/j.asr.2020.04.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96369
in Advances in space research > vol 66 n° 3 (1 August 2020) . - pp 469 - 489[article]
Titre : Automated estimation and tools to extract positions, velocities, breaks, and seasonal terms from daily GNSS measurements: illuminating nonlinear Salton Trough deformation Type de document : Article/Communication Auteurs : Michael B. Heflin, Auteur ; Andrea Donnellan, Auteur ; Jay Parker, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : 10 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] chaîne de traitement
[Termes IGN] champ de vitesse
[Termes IGN] déformation horizontale de la croute terrestre
[Termes IGN] données GNSS
[Termes IGN] dorsale
[Termes IGN] faille géologique
[Termes IGN] modèle géologique
[Termes IGN] positionnement par GNSS
[Termes IGN] série temporelle
[Termes IGN] sismologie
[Termes IGN] station GPS
[Termes IGN] valeur aberrante
[Termes IGN] variation saisonnièreRésumé : (auteur) This paper describes the methods used to estimate positions, velocities, breaks, and seasonalterms from daily Global Navigation Satellite System (GNSS) measurements. Break detection and outlierremoval have been automated so that decades of daily measurements from thousands of stations can beprocessed in a few hours. New measurements are added, and parameters are updated every week. Modelparameters allow separation of interseismic, annual, coseismic, and postseismic signals. Tools availablethrough GeoGateway (http://geo-gateway.org) allow rapid visualization and analysis of these terms forresults that can be subsetted in time or space. Results show highly variable and nonlinear motion for GPSstations in southern California. The variable motion is related to seasonal motions, distributed tectonicmotion, earthquakes, and postseismic motions that can continue for years. In some areas results suggest thatadditional processes are responsible for the observed motions. In general, following earthquakes, stationsreturn to their longterm motions after 2–3 years, though some exceptions occur. The use of the tools showsnonlinear motion in the Salton Trough of southern California related to the 2010 M7.2 El MayorCucapahearthquake, 2012 Brawley earthquake swarm, and a creep event on the Superstition Hills fault in 2017. Numéro de notice : A2020-446 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2019EA000644 Date de publication en ligne : 18/05/2020 En ligne : https://doi.org/10.1029/2019EA000644 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95516
in Earth and space science > vol 7 n° 7 (July 2020) . - 10 p.[article]
Titre : Is the Jason-2 DORIS oscillator also affected by the South Atlantic Anomaly? Type de document : Article/Communication Auteurs : Pascal Willis Année de publication : 2016 Article en page(s) : pp 2617 - 2627 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] anomalie de Bouguer
[Termes IGN] Atlantique Sud
[Termes IGN] co-positionnement
[Termes IGN] données DORIS
[Termes IGN] données GPS
[Termes IGN] erreur systématique
[Termes IGN] Jason
[Termes IGN] oscillateur
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résidu
[Termes IGN] série temporelle
[Termes IGN] station permanenteRésumé : (auteur) We analyzed time series of daily DORIS and GPS station coordinate estimates derived from Precise Point Positioning (PPP). The DORIS coordinates were estimated using Jason-2 precise orbits based on GPS data only, implying that the station positions from the two techniques are expressed in the same GPS-based terrestrial reference frame. Comparisons of 3-D vectors of such co-located stations show systematic biases in position around South America when compared to local geodetic ties. We conclude that these results could be explained by a sensitivity of the Jason-2/DORIS oscillator to radiation when the satellite passes over the South Atlantic Anomaly (SAA). The effect for Jason-2 manifests mainly as an offset in station coordinates, though there is also evidence of a drift at the start of the mission that diminishes in time. This contrasts with the experience on Jason-1, wherein large, persistent drifts were observed for stations in this same (SAA) region. The spurious drift is much (∼90%) smaller for Jason-2, which may be attributable to the steps taken prior to launch to harden the oscillator. Analysis of DORIS Doppler residuals may indicate some small degradation after 2009 for these stations. Numéro de notice : A2016--178 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2016.09.015 Date de publication en ligne : 21/09/2016 En ligne : https://doi.org/10.1016/j.asr.2016.09.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91806
in Advances in space research > vol 58 n° 12 (15 December 2016) . - pp 2617 - 2627[article]
Titre : DPOD2008, A DORIS-oriented terrestrial reference frame for precise orbit determination Type de document : Article/Communication Auteurs : Pascal Willis Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2016 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 143 Conférence : IAG 2013, Scientific assembly, IAG 150 Years Postdam Allemagne Proceedings Springer Importance : pp 175 - 181 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] Jason
[Termes IGN] orbitographie
[Termes IGN] repère de référence
[Termes IGN] station de poursuiteRésumé : (auteur) While accuracy of tracking station coordinates is of key importance for Precise Orbit Determination (POD) for altimeter satellites, reliability and operationality are also of great concern. In particular, while recent ITRF realizations should be the most accurate at the time of their computation, they cannot be directly used by the POD groups for operational consideration for several reasons such as new stations appearing in the network or new discontinuities affecting station coordinates. For POD purposes, we computed a new DORIS terrestrial frame called DPOD2008 derived from ITRF2008 (as previously done by DPOD2005 with regards to ITRF2005). In a first step, we will present the method used to validate the past ITRF2008 using more recent DORIS data and to derive new station positions and velocities, when needed. In particular, discontinuities in DORIS station positions and/or velocities are discussed. To derive new DORIS station coordinates, we used recent DORIS weekly time series of coordinates, recent GPS relevant time series at co-located sites and also dedicated GPS campaigns performed by IGN when installing new DORIS beacons. DPOD2008 also contains additional metadata that are useful when processing DORIS data, for example, periods during which DORIS data should not be used or at least for which data should be downweighted. In several cases, a physical explanation can be found for such temporary antenna instability. We then demonstrate improvements seen when using different reference frames, such as the original ITRF2008 solution, for precise orbit determination of altimeter satellites TOPEX/Poseidon and Jason-2 over selected periods spanning 1993–2013. Numéro de notice : C2013-052 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1007/1345_2015_125 Date de publication en ligne : 07/07/2015 En ligne : http://dx.doi.org/10.1007/1345_2015_125 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78500 
Titre : KALREF, a Kalman filter and time series approach to the International Terrestrial Reference Frame realization Type de document : Article/Communication Auteurs : Xiaoping Wu, Auteur ; Claudio Abbondanza, Auteur ; Zuheir Altamimi Année de publication : 2015 Article en page(s) : pp 3775 - 3802 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] filtre de Kalman
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] point de liaison (géodésie)
[Termes IGN] série temporelle
[Termes IGN] vitesseRésumé : (auteur) The current International Terrestrial Reference Frame is based on a piecewise linear site motion model and realized by reference epoch coordinates and velocities for a global set of stations. Although linear motions due to tectonic plates and glacial isostatic adjustment dominate geodetic signals, at today's millimeter precisions, nonlinear motions due to earthquakes, volcanic activities, ice mass losses, sea level rise, hydrological changes, and other processes become significant. Monitoring these (sometimes rapid) changes desires consistent and precise realization of the terrestrial reference frame (TRF) quasi-instantaneously. Here, we use a Kalman filter and smoother approach to combine time series from four space geodetic techniques to realize an experimental TRF through weekly time series of geocentric coordinates. In addition to secular, periodic, and stochastic components for station coordinates, the Kalman filter state variables also include daily Earth orientation parameters and transformation parameters from input data frames to the combined TRF. Local tie measurements among colocated stations are used at their known or nominal epochs of observation, with comotion constraints applied to almost all colocated stations. The filter/smoother approach unifies different geodetic time series in a single geocentric frame. Fragmented and multitechnique tracking records at colocation sites are bridged together to form longer and coherent motion time series. While the time series approach to TRF reflects the reality of a changing Earth more closely than the linear approximation model, the filter/smoother is computationally powerful and flexible to facilitate incorporation of other data types and more advanced characterization of stochastic behavior of geodetic time series. Numéro de notice : A2015--006 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Autre URL associée : http://onlinelibrary.wiley.com/doi/10.1002/2014JB011622 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/2014JB011622 Date de publication en ligne : 07/04/2015 En ligne : http://dx.doi.org/10.1002/2014JB011622 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80479
in Journal of geophysical research : Solid Earth > vol 120 n° 5 (May 2015) . - pp 3775 - 3802[article]Documents numériques
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