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Maintaining real-time precise point positioning during outages of orbit and clock corrections / Ahmed El-Mowafy in GPS solutions, vol 21 n° 3 (July 2017)
[article]
Titre : Maintaining real-time precise point positioning during outages of orbit and clock corrections Type de document : Article/Communication Auteurs : Ahmed El-Mowafy, Auteur ; Manoj Deo, Auteur ; Nobuaki Kubo, Auteur Année de publication : 2017 Article en page(s) : pp 937 – 947 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] horloge
[Termes IGN] International GNSS Service
[Termes IGN] international GPS service for geodynamics
[Termes IGN] interruption du signal
[Termes IGN] orbitographie
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision décimétrique
[Termes IGN] prévisionRésumé : (auteur) The precise point positioning (PPP) is a popular positioning technique that is dependent on the use of precise orbits and clock corrections. One serious problem for real-time PPP applications such as natural hazard early warning systems and hydrographic surveying is when a sudden communication break takes place resulting in a discontinuity in receiving these orbit and clock corrections for a period that may extend from a few minutes to hours. A method is presented to maintain real-time PPP with 3D accuracy less than a decimeter when such a break takes place. We focus on the open-access International GNSS Service (IGS) real-time service (RTS) products and propose predicting the precise orbit and clock corrections as time series. For a short corrections outage of a few minutes, we predict the IGS-RTS orbits using a high-order polynomial, and for longer outages up to 3 h, the most recent IGS ultra-rapid orbits are used. The IGS-RTS clock corrections are predicted using a second-order polynomial and sinusoidal terms. The model parameters are estimated sequentially using a sliding time window such that they are available when needed. The prediction model of the clock correction is built based on the analysis of their properties, including their temporal behavior and stability. Evaluation of the proposed method in static and kinematic testing shows that positioning precision of less than 10 cm can be maintained for up to 2 h after the break. When PPP re-initialization is needed during the break, the solution convergence time increases; however, positioning precision remains less than a decimeter after convergence. Numéro de notice : A2017-442 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0583-4 En ligne : https://doi.org/10.1007/s10291-016-0583-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86360
in GPS solutions > vol 21 n° 3 (July 2017) . - pp 937 – 947[article]Determination of a high spatial resolution geopotential model using atomic clock comparisons / Guillaume Lion in Journal of geodesy, vol 91 n° 6 (June 2017)
[article]
Titre : Determination of a high spatial resolution geopotential model using atomic clock comparisons Type de document : Article/Communication Auteurs : Guillaume Lion , Auteur ; Isabelle Panet , Auteur ; Peter Wolf, Auteur ; C. Guerlin, Auteur ; Sébastien Bize, Auteur ; Pacôme Delva, Auteur Année de publication : 2017 Projets : FIRST-TF / , AdOC / , ITOC / Article en page(s) : pp 597 - 611 Note générale : Bibliographie
We gratefully acknowledge financial support from Labex FIRST-TF, ERC AdOC(Grant No. 617553 and EMRP ITOC (EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union).Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Alpes (France)
[Termes IGN] champ de pesanteur local
[Termes IGN] collocation par moindres carrés
[Termes IGN] covariance
[Termes IGN] erreur systématique
[Termes IGN] horloge atomique
[Termes IGN] horlogerie
[Termes IGN] levé gravimétrique
[Termes IGN] Massif central (France)
[Termes IGN] modèle de géopotentiel local
[Termes IGN] qualité des donnéesRésumé : (Auteur) Recent technological advances in optical atomic clocks are opening new perspectives for the direct determination of geopotential differences between any two points at a centimeter-level accuracy in geoid height. However, so far detailed quantitative estimates of the possible improvement in geoid determination when adding such clock measurements to existing data are lacking. We present a first step in that direction with the aim and hope of triggering further work and efforts in this emerging field of chronometric geodesy and geophysics. We specifically focus on evaluating the contribution of this new kind of direct measurements in determining the geopotential at high spatial resolution (≈10 km). We studied two test areas, both located in France and corresponding to a middle (Massif Central) and high (Alps) mountainous terrain. These regions are interesting because the gravitational field strength varies greatly from place to place at high spatial resolution due to the complex topography. Our method consists in first generating a synthetic high-resolution geopotential map, then drawing synthetic measurement data (gravimetry and clock data) from it, and finally reconstructing the geopotential map from that data using least squares collocation. The quality of the reconstructed map is then assessed by comparing it to the original one used to generate the data. We show that adding only a few clock data points (less than 1% of the gravimetry data) reduces the bias significantly and improves the standard deviation by a factor 3. The effect of the data coverage and data quality on the results is investigated, and the trade-off between the measurement noise level and the number of data points is discussed. Numéro de notice : A2017-286 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0986-6 Date de publication en ligne : 11/01/2017 En ligne : http://dx.doi.org/10.1007/s00190-016-0986-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85319
in Journal of geodesy > vol 91 n° 6 (June 2017) . - pp 597 - 611[article]Documents numériques
en open access
Determination of a high spatial resolution ... - pdf éditeurAdobe Acrobat PDF NRC Remote clock secure dissemination of traceable time / Marina Gertsvolf in Inside GNSS, vol 12 n° 3 (May - June 2017)
[article]
Titre : NRC Remote clock secure dissemination of traceable time Type de document : Article/Communication Auteurs : Marina Gertsvolf, Auteur ; John Bernard, Auteur ; André Charbonneau, Auteur ; Bill Hoger, Auteur ; Hai Pham, Auteur Année de publication : 2017 Article en page(s) : pp 42 - 47 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Canada
[Termes IGN] chronométrie
[Termes IGN] horloge atomique
[Termes IGN] incertitude temporelle
[Termes IGN] synchronisationRésumé : (auteur) The demand for secure and accurate time has been growing in recent years in telecommunications, infrastructure, navigation and finance. The requirements are for traceable time with sub micro-second precision. Currently available methods have technical or reliability limitations in achieving this goal. In this article the authors will discuss how the NRC Remote Clock product offers secure traceable time dissemination to a remote user. Our method achieves few tens of nanoseconds uncertainty and relies on a remote high quality clock that synchronizes its time with the clock run at the National Research Council (NRC) main lab in Ottawa, Canada. Numéro de notice : A2017-258 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.insidegnss.com/node/5466 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85275
in Inside GNSS > vol 12 n° 3 (May - June 2017) . - pp 42 - 47[article]Galileo face à une panne d'horloge / Anonyme in Géomètre, n° 2147 (mai 2017)
[article]
Titre : Galileo face à une panne d'horloge Type de document : Article/Communication Auteurs : Anonyme, Auteur Année de publication : 2017 Article en page(s) : pp 11 - 11 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] constellation Galileo
[Termes IGN] Galileo
[Termes IGN] horloge atomique
[Termes IGN] panne
[Termes IGN] précision du positionnementRésumé : (Auteur) Avec dix-huit satellites en service, Galileo, le GNSS européen, est officiellement entré en service fin 2016. Mais les contretemps s'accumulent ... Numéro de notice : A2017-200 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84951
in Géomètre > n° 2147 (mai 2017) . - pp 11 - 11[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 063-2017051 RAB Revue Centre de documentation En réserve L003 Disponible Multi-GNSS precise point positioning (MGPPP) using raw observations / Teng Liu in Journal of geodesy, vol 91 n° 3 (March 2017)
[article]
Titre : Multi-GNSS precise point positioning (MGPPP) using raw observations Type de document : Article/Communication Auteurs : Teng Liu, Auteur ; Yunbin Yuan, Auteur ; Baocheng Zhang, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 253 - 268 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] correction ionosphérique
[Termes IGN] données BeiDou
[Termes IGN] données Galileo
[Termes IGN] données GLONASS
[Termes IGN] données GPS
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] horloge atomique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] simple différence
[Vedettes matières IGN] Traitement de données GNSSMots-clés libres : Multi-GNSS Experiment (MGEX) Résumé : (Auteur) A joint-processing model for multi-GNSS (GPS, GLONASS, BDS and GALILEO) precise point positioning (PPP) is proposed, in which raw code and phase observations are used. In the proposed model, inter-system biases (ISBs) and GLONASS code inter-frequency biases (IFBs) are carefully considered, among which GLONASS code IFBs are modeled as a linear function of frequency numbers. To get the full rank function model, the unknowns are re-parameterized and the estimable slant ionospheric delays and ISBs/IFBs are derived and estimated simultaneously. One month of data in April, 2015 from 32 stations of the International GNSS Service (IGS) Multi-GNSS Experiment (MGEX) tracking network have been used to validate the proposed model. Preliminary results show that RMS values of the positioning errors (with respect to external double-difference solutions) for static/kinematic solutions (four systems) are 6.2 mm/2.1 cm (north), 6.0 mm/2.2 cm (east) and 9.3 mm/4.9 cm (up). One-day stabilities of the estimated ISBs described by STD values are 0.36 and 0.38 ns, for GLONASS and BDS, respectively. Significant ISB jumps are identified between adjacent days for all stations, which are caused by the different satellite clock datums in different days and for different systems. Unlike ISBs, the estimated GLONASS code IFBs are quite stable for all stations, with an average STD of 0.04 ns over a month. Single-difference experiment of short baseline shows that PPP ionospheric delays are more precise than traditional leveling ionospheric delays. Numéro de notice : A2017-065 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0960-3 En ligne : http://dx.doi.org/10.1007/s00190-016-0960-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84290
in Journal of geodesy > vol 91 n° 3 (March 2017) . - pp 253 - 268[article]PermalinkSpringer handbook of Global Navigation Satellite Systems / Peter J.G. Teunissen (2017)PermalinkBetter GNSS navigation and spoofing detection with chip scale-atomic clocks / Thomas Krawinkel in GPS world, vol 27 n° 10 (October 2016)PermalinkHigh rate 30 seconds vs clock interpolation in precise point positioning (PPP) / Sorin Nistor in Geodetski vestnik, vol 60 n° 3 (September - November 2016)PermalinkA remark on the GNSS single difference model with common clock scheme for attitude determination / Wantong Chen in Journal of applied geodesy, vol 10 n° 3 (September 2016)PermalinkIdentifying a low-frequency oscillation in Galileo IOV pseudorange rates / Daniele Borio in GPS solutions, vol 20 n° 3 (July 2016)PermalinkPerformance of real-time Precise Point Positioning using IGS real-time service / Mohamed Elsobeiey in GPS solutions, vol 20 n° 3 (July 2016)PermalinkPotential of GPS common clock single-differences for deformation monitoring / Steffen Schön in Journal of applied geodesy, vol 10 n° 1 (March 2016)PermalinkPermalinkImpacts of real-time satellite clock errors on GPS precise point positioning-based troposphere zenith delay estimation / Junbo Shi in Journal of geodesy, vol 89 n° 8 (August 2015)PermalinkSingle-frequency precise point positioning: an analytical approach / Oskar Sterle in Journal of geodesy, vol 89 n° 8 (August 2015)PermalinkThe clock at the center of the universe / Gavin Schrock in xyHt, vol 2015 n° 6 (June 2015)PermalinkEstimating the short-term stability of in-orbit GNSS clocks : Following launch on GEO/GSO satellites / Dhaval Upadhyay in Inside GNSS, vol 10 n° 3 (May - June 2015)PermalinkReal-time clock jump compensation for precise point positioning / Fei Guo in GPS solutions, vol 18 n° 1 (january 2014)PermalinkCalibration of the clock-phase biases of GNSS networks: the closure-ambiguity approach / A. Lannes in Journal of geodesy, vol 87 n° 8 (August 2013)PermalinkStochastic modeling of high-stability ground clocks in GPS analysis / Kang Wang in Journal of geodesy, vol 87 n° 5 (May 2013)PermalinkLe positionnement par satellites et les maths / Jonathan Chenal in Tangente, n° 151 (mars-avril 2013)PermalinkPerformance of real-time precise point positioning / Junping Chen in Marine geodesy, vol 36 n° 1 (January - March 2013)PermalinkTime, atomics clocks and relativistic geodesy / Enrico Mai (2013)PermalinkGalileo, un système global de positionnement par satellites / Jonathan Chenal (2012)Permalink