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Resolution of GPS carrier-phase ambiguities in Precise Point Positioning (PPP) with daily observations / M. Ge in Journal of geodesy, vol 82 n° 7 (July 2008)
[article]
Titre : Resolution of GPS carrier-phase ambiguities in Precise Point Positioning (PPP) with daily observations Type de document : Article/Communication Auteurs : M. Ge, Auteur ; Gerd Gendt, Auteur ; Markus Rothacher, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 389 - 401 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] double différence
[Termes IGN] mesurage de phase
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Termes IGN] simple différenceRésumé : (Auteur) Precise Point Positioning (PPP) has been demonstrated to be a powerful tool in geodetic and geodynamic applications. Although its accuracy is almost comparable with network solutions, the east component of the PPP results is still to be improved by integer ambiguity fixing, which is, up to now, prevented by the presence of the uncalibrated phase delays (UPD) originating in the receivers and satellites. In this paper, it is shown that UPDs are rather stable in time and space, and can be estimated with high accuracy and reliability through a statistical analysis of the ambiguities estimated from a reference network. An approach is implemented to estimate the fractional parts of the single-difference (SD) UPDs between satellites in wide- and narrow-lane from a global reference network. By applying the obtained SD-UPDs as corrections to the SD-ambiguities at a single station, the corrected SD-ambiguities have a naturally integer feature and can therefore be fixed to integer values as usually done for the double-difference ones in the network mode. With data collected at 450 stations of the International GNSS Service (IGS) through days 106 to 119 in 2006, the efficiency of the presented ambiguity-fixing strategy is validated using IGS Final products. On average, more than 80% of the independent ambiguities could be fixed reliably, which leads to an improvement of about 27% in the repeatability and 30% in the agreement with the IGS weekly solutions for the east component of station coordinates, compared with the real-valued solutions. Copyright Springer Numéro de notice : A2008-317 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-007-0187-4 En ligne : https://doi.org/10.1007/s00190-007-0187-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29310
in Journal of geodesy > vol 82 n° 7 (July 2008) . - pp 389 - 401[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 266-08061 RAB Revue Centre de documentation En réserve L003 Disponible 266-08062 RAB Revue Centre de documentation En réserve L003 Disponible The future is now GPS + GLONASS + SBAS = GNSS / Lambert Wanninger in GPS world, vol 19 n° 7 (July 2008)
[article]
Titre : The future is now GPS + GLONASS + SBAS = GNSS Type de document : Article/Communication Auteurs : Lambert Wanninger, Auteur Année de publication : 2008 Article en page(s) : pp 42 - 48 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] BeiDou
[Termes IGN] Global Navigation Satellite System
[Termes IGN] positionnement par EGNOS
[Termes IGN] positionnement par Galileo
[Termes IGN] positionnement par GLONASS
[Termes IGN] positionnement par GPS
[Termes IGN] système de positionnement par satellitesRésumé : (Auteur) We are on the brink of a new era in satellite positioning and navigation. The excitement that was felt 30 years ago when the first GPS satellite was launched is beginning to be felt again. Back then, instantaneous three-dimensional satellite-based positioning was an entirely new concept. Yes, we did have satellite-based positioning before GPS, but it wasn't instantaneous and it wasn't fully 3D - nor was it very accurate. Over the past 30 years, thousands of scientists and engineers have developed an amazing range of GPS applications providing positioning accuracies all the way down to the millimeter level. However, some would argue that many of the recent developments, especially in the area of high-accuracy positioning, are just minor enhancements to existing techniques first introduced or foretold years ago. Been there, done that. But that situation is about to change -and in a big way! New signals and new satellites herald a new era in satellite-based positioning and navigation. Russia's Global'naya Navigatsionnaya Sputnikovaya Sistema (GLONASS) is being revitalized after many years of neglect. With its first launch in 1982, this second global navigation satellite system gave rise to the generic term for all such systems : GNSS. In addition to GLONASS and a modernized GPS featuring new civil and military signals along with new constellations of satellites, we will have Europe's Galileo system (with two GIOVE test satellites already in orbit) and China's Beidou/Compass system (with five satellites already in orbit). Receivers and data-processing techniques will be developed to allow use of all available signals and satellites. The future promises to be just as exciting for GNSS scientists and engineers as the early days of GPS. But do we have to wait for these new or enhanced systems to be in place before benefiting from a multi-signal, multi-constellation global navigation satellite system? Definitely not. As this month's column describes, we can sample the future to day. The existing GPS satellites, along with the revitalized GLONASS constellation and the satellites of the various geostationary satellite-based augmentation systems, already constitute a system of systems. And receivers currently on the market provide the necessary raw measurement data to yield positioning solutions from this system of systems with potentially more continuity and greater accuracy than those obtained using GPS alone. Listen up: the future is now. Copyright Questex Media Group Inc Numéro de notice : A2008-299 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29292
in GPS world > vol 19 n° 7 (July 2008) . - pp 42 - 48[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 067-08071 RAB Revue Centre de documentation En réserve L003 Disponible Accuracy assessment of Lidar-derived digital elevation models / F. Aguilar in Photogrammetric record, vol 23 n° 122 (June - August 2008)
[article]
Titre : Accuracy assessment of Lidar-derived digital elevation models Type de document : Article/Communication Auteurs : F. Aguilar, Auteur ; Jon P. Mills, Auteur Année de publication : 2008 Article en page(s) : pp 148 - 169 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse comparative
[Termes IGN] données lidar
[Termes IGN] erreur de mesure
[Termes IGN] lasergrammétrie
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle numérique de surface
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement par GPS
[Termes IGN] précision des mesuresRésumé : (Auteur) Despite the relatively high cost of airborne lidar-derived digital elevation models (DEMs), such products are usually presented without a satisfactory associated estimate of accuracy. For the most part, DEM accuracy estimates are typically provided by comparing lidar heights against a finite sample of check point coordinates from an independent source of higher accuracy, supposing a normal distribution of the derived height differences or errors. This paper proposes a new methodology to assess the vertical accuracy of lidar DEMs using confidence intervals constructed from a finite sample of errors computed at check points. A non-parametric approach has been tested where no particular error distribution is assumed, making the proposed methodology especially applicable to non-normal error distributions of the type usually found in DEMs derived from lidar. The performance of the proposed model was experimentally validated using Monte Carlo simulation on 18 vertical error data-sets. Fifteen of these data-sets were computed from original lidar data provided by the International Society for Photogrammetry and Remote Sensing Working Group III/3, using their respective filtered reference data as ground truth. The three remaining data-sets were provided by the Natural Environment Research Council's Airborne Research and Survey Facility lidar system, together with check points acquired using high precision kinematic GPS. The results proved promising, the proposed models reproducing the statistical behaviour of vertical errors of lidar using a favourable number of check points, even in the cases of data-sets with non-normally distributed residuals. This research can therefore be considered as a potentially important step towards improving the quality control of lidar-derived DEMs. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2008-295 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2008.00476.x En ligne : https://doi.org/10.1111/j.1477-9730.2008.00476.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29288
in Photogrammetric record > vol 23 n° 122 (June - August 2008) . - pp 148 - 169[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 106-08021 RAB Revue Centre de documentation En réserve L003 Disponible Comparaison du positionnement temps réel classique RTK et du positionnement GPS temps réel réseau : mise en oeuvre dans le réseau Orphéon / Laurent Morel in XYZ, n° 115 (juin - août 2008)
[article]
Titre : Comparaison du positionnement temps réel classique RTK et du positionnement GPS temps réel réseau : mise en oeuvre dans le réseau Orphéon Type de document : Article/Communication Auteurs : Laurent Morel, Auteur ; Stéphane Durand, Auteur Année de publication : 2008 Article en page(s) : pp 29 - 38 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse comparative
[Termes IGN] norme RTCM
[Termes IGN] Orphéon
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement par GNSS
[Termes IGN] station GPS
[Termes IGN] temps réelRésumé : (Auteur) Plusieurs réseaux GPS temps réel poursuivent leur implantation sur le territoire national pour délivrer de nouveaux services de positionnement par GNSS. En s'appuyant sur les principes du RTK avec une seule station, cet article explicite le concept maître auxiliaire à la base de la nouvelle norme de transmission RTCM version 3. Nous présentons ensuite les résultats d'une campagne de mesures mettant en œuvre ces deux types de positionnement : le RTK classique et le RTK dans le réseau Orphéon. Afin de comparer ces deux modes de positionnement RTK, nous avons fait varier la distance à la station de référence utilisée pour le mode RTK classique, utilisé les mêmes observations pour les deux calculs en temps réel, considéré différents environnements (rural, semi-urbain, urbain). Nous avons également comparé les positions RTK à des positions RGF93 obtenues par post-traitement. Les principaux résultats montrent une précision du positionnement RTK réseau d'au moins aussi bonne qualité que le positionnement RTK classique et de l'ordre de 2 cm. Les temps d'initialisation sont également similaires et proches de 10 secondes en moyenne. Copyright AFT Numéro de notice : A2008-264 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29259
in XYZ > n° 115 (juin - août 2008) . - pp 29 - 38[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 112-08021 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Ocean tide loading (OTL) displacements from global and local grids: comparisons to GPS estimates over the shelf of Brittany, France / Stavros A. Melachroinos in Journal of geodesy, vol 82 n° 6 (June 2008)
[article]
Titre : Ocean tide loading (OTL) displacements from global and local grids: comparisons to GPS estimates over the shelf of Brittany, France Type de document : Article/Communication Auteurs : Stavros A. Melachroinos, Auteur ; Richard Biancale, Auteur ; Muriel Llubes, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 357 - 371 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] baie
[Termes IGN] Bretagne
[Termes IGN] Cotentin
[Termes IGN] marée océanique
[Termes IGN] modèle physique
[Termes IGN] Mont-Saint-Michel
[Termes IGN] plateau continental
[Termes IGN] positionnement par GPS
[Termes IGN] série temporelle
[Termes IGN] surcharge océanique
[Termes IGN] trajet multipleRésumé : (Auteur) In this paper we examine OTL displacements detected by GPS stations of a dedicated campaign and validate ocean tide models. Our area of study is the continental shelf of Brittany and Cotentin in France. Brittany is one of the few places in the world where tides provoke loading displacements of ?10–12 cm vertically and a few cm horizontally. Ocean tide models suffer from important discrepancies in this region. Seven global and regional ocean tide models were tested: FES2004 corrected for K2, TPXO.7.0, TPXO.6.2, GOT00.2, CSR4.0, NAO.99b and the most recent regional grids of the North East Atlantic (NEA2004). These gridded amplitudes and phases of ocean tides were convolved in order to get the predicted OTL displacements using two different algorithms. Data over a period of 3.5 months of 8 GPS campaign stations located on the north coast of Brittany are used, in order to evaluate the geographical distribution of the OTL effect. We have modified and implemented new algorithms in our GPS software, GINS 7.1. GPS OTL constituents are estimated based on 1-day batch solutions. We compare the observed GPS OTL constituents of M2, S2, N2 and K1 waves with the selected ocean tide models on global and regional grids. Large phase-lag and amplitude discrepancies over 20° and 1.5 cm in the vertical direction in the semi-diurnal band of M2 between predictions and GPS/models are detected in the Bay of Mont St-Michel. From a least squares spectral analysis of the GPS time-series, significant harmonic peaks in the integer multiples of the orbital periods of the GPS satellites are observed, indicating the existence of multipath effects in the GPS OTL constituents. The GPS OTL observations agree best with FES2004, NEA2004, GOT00.2 and CSR4.0 tide models. Copyright Springer Numéro de notice : A2008-315 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-007-0185-6 En ligne : https://doi.org/10.1007/s00190-007-0185-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29308
in Journal of geodesy > vol 82 n° 6 (June 2008) . - pp 357 - 371[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 266-08051 SL Revue Centre de documentation Revues en salle Disponible Comment se localise-t-on par satellite ? / Julien Bourdet in Ciel et Espace, n° 456 (01/05/2008)PermalinkPerformance of GPS precise point positioning under conifer forest canopies / Erik Naesset in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 5 (May 2008)PermalinkA GNSS odometer: how far have we come? / Andreas Wieser in GPS world, vol 19 n° 4 (April 2008)PermalinkReal-time kinematic GPS positioning / P. Haase in Geoinformatics, vol 11 n° 3 (01/04/2008)PermalinkA compression format and tools for GNSS observation data / Yuki Hatanaka in Bulletin of the Geographical survey institute, vol 55 (March 2008)PermalinkLe forum GPS de l'ENSG / Anonyme in Géomatique expert, n° 61 (01/03/2008)PermalinkImproving long-range RTK: getting a better handle on the biases / D. Kim in GPS world, vol 19 n° 3 (March 2008)PermalinkOfficial GNSS-derived vertical orthometric height control network / G. Steinberg in SaLIS Surveying and land information science, vol 68 n° 1 (March 2008)PermalinkTheory and reality of direct georeferencing in national coordinates / Jan Skaloud in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 2 (March - April 2008)PermalinkAnalyse des séries temporelles de positions des stations de géodésie spatiale : application au repère international de référence terrestre (ITRF) / Xavier Collilieux (2008)PermalinkPermalinkContinous mobile laser scanning / F. Zampa in GIM international, vol 22 n° 1 (January 2008)PermalinkEntwicklung eines Qualitätsmodells für die Generierung von digitalen Gelandemodellen aus airborne Laser scanning / Hans Jürg Luthy (2008)PermalinkEtude sur la restitution fine de l'axe de visée d'un instrument optronique embarqué / Adeline Coupé (2008)PermalinkGalileo / François Barlier (2008)PermalinkGood, better, best: expanding the wide area augmentation system / T. Schrempp in GPS world, vol 19 n° 1 (January 2008)PermalinkGPS composite clock analysis / James R. Wright in International Journal of Navigation and Observation, vol 2008 (01/01/2008)PermalinkHEPOS : designing and implementating an RTK network / M. Gianniou in Geoinformatics, vol 11 n° 1 (01/01/2008)PermalinkInternational Calibration and Orientation Workshop, EuroCOW 2008, 30 janvier - 1er février 2008, Castelldefels, Espagne / Ismael Colomina (2008)PermalinkKalman filtering, theory and practice using MATLAB / Mohinder S. Grewal (2008)Permalink