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Impact of the network effect on the origin and scale: case study of Satellite Laser Ranging / Xavier Collilieux (2009)
Titre : Impact of the network effect on the origin and scale: case study of Satellite Laser Ranging Type de document : Article/Communication Auteurs : Xavier Collilieux , Auteur ; Zuheir Altamimi , Auteur Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2009 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 133 Conférence : IAG 2007, International Association of Geodesy General Assembly Perugia Italie Proceedings Springer Importance : pp 31 - 37 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] analyse de sensibilité
[Termes IGN] données GPS
[Termes IGN] données TLS (télémétrie)
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] mouvement du géocentre
[Termes IGN] repère de référence
[Termes IGN] station permanente
[Termes IGN] transformation de HelmertRésumé : (auteur) The study of station non linear motions requires being able to discriminate between the local motion of every station and their global motion (e.g. geocenter motion). A common used approach consists in estimating Helmert parameters with respect to a secular reference frame. But if the network is small or not well distributed, the global parameters, and mainly the translation and scale parameters, will not be rigorously decorrelated from the station displacements. The distribution of the currently operating Satellite Laser Ranging (SLR) stations is one example of such a network. The understanding of the network effect needs an analysis of the station distribution over time. It appears that SLR station distribution on the X positive hemisphere of the Earth varies seasonally. We suggest here that using GPS results to constrain the estimation of SLR station displacements may improve the estimation of the Helmert parameters. These additional constraints as well as stochastic constraints are numerically tested here in a first attempt to limit the impact of the network effect. We show that the X component of the translation and the scale are the two parameters that are the most sensitive to any change in the configuration of the added constraints. Numéro de notice : C2009-027 Affiliation des auteurs : LAREG (1991-2011) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1007/978-3-540-85426-5_4 En ligne : https://doi.org/10.1007/978-3-540-85426-5_4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90615 West African Monsoon observed with ground-based GPS receivers during African Monsoon Multidisciplinary Analysis (AMMA) / Olivier Bock in Journal of geophysical research : Atmospheres, vol 113 n° D21 (16 November 2008)
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Titre : West African Monsoon observed with ground-based GPS receivers during African Monsoon Multidisciplinary Analysis (AMMA) Type de document : Article/Communication Auteurs : Olivier Bock , Auteur ; Marie-Noëlle Bouin , Auteur ; Erik Doerflinger, Auteur ; Philippe Collard, Auteur ; Florian Masson, Auteur ; Rémi Meynadier, Auteur ; Samuel Nahmani , Auteur ; et al., Auteur Année de publication : 2008 Projets : AMMA & AMMA-2 / Janicot, Serge Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Afrique occidentale
[Termes IGN] circulation atmosphérique
[Termes IGN] données GPS
[Termes IGN] erreur systématique
[Termes IGN] humidité de l'air
[Termes IGN] modèle de simulation
[Termes IGN] mousson
[Termes IGN] phénomène atmosphérique
[Termes IGN] précipitation
[Termes IGN] vapeur d'eau
[Termes IGN] variation saisonnièreRésumé : (auteur) A ground-based GPS network has been established over West Africa in the framework of African Monsoon Multidisciplinary Analysis (AMMA) in tight cooperation between French and African institutes. The experimental setup is described and preliminary highlights are given for different applications using these data. Precipitable water vapor (PWV) estimates from GPS are used for evaluating numerical weather prediction (NWP) models and radiosonde humidity data. Systematic tendency errors in model forecasts are evidenced. Correlated biases in NWP model analyses and radiosonde data are evidenced also, which emphasize the importance of radiosonde humidity data in this region. PWV and precipitation are tightly correlated at seasonal and intraseasonal timescales. Almost no precipitation occurs when PWV is smaller than 30 kg m−2. This limit in PWV also coincides well with the location of the intertropical discontinuity. Five distinct phases in the monsoon season are determined from the GPS PWV, which correspond either to transition or stationary periods of the West African Monsoon system. They may serve as a basis for characterizing interannual variability. Significant oscillations in PWV are observed with 10- to 15-day and 15- to 20-day periods, which suggest a strong impact of atmospheric circulation on moisture and precipitation. The presence of a diurnal cycle oscillation in PWV with marked seasonal evolutions is found. This oscillation involves namely different phasing of moisture fluxes in different layers implying the low-level jet, the return flow, and the African Easterly Jet. The broad range of timescales observed with the GPS systems shows a high potential for investigating many atmospheric processes of the West African Monsoon. Numéro de notice : A2008-656 Affiliation des auteurs : LAREG+Ext (1991-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2008JD010327 Date de publication en ligne : 05/11/2008 En ligne : https://doi.org/10.1029/2008JD010327 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98266
in Journal of geophysical research : Atmospheres > vol 113 n° D21 (16 November 2008)[article]Correction of humidity bias for Vaïsala RS80 sondes during AMMA 2006 Observing Period / Mathieu Nuret in Journal of Atmospheric and Oceanic Technology, vol 25 n° 11 (November 2008)
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Titre : Correction of humidity bias for Vaïsala RS80 sondes during AMMA 2006 Observing Period Type de document : Article/Communication Auteurs : Mathieu Nuret, Auteur ; Jean-Philippe Lafore, Auteur ; Françoise Guichard, Auteur ; Jean-Luc Redelsperger, Auteur ; Olivier Bock , Auteur ; Anna Agusti-Panareda, Auteur ; Jean-Blaise N’Gamini, Auteur Année de publication : 2008 Article en page(s) : pp 2152 - 2158 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Afrique occidentale
[Termes IGN] données GPS
[Termes IGN] données météorologiques
[Termes IGN] erreur systématique
[Termes IGN] humidité de l'air
[Termes IGN] mousson
[Termes IGN] radiosondageRésumé : (autuer) During the African Monsoon Multidisciplinary Analyses (AMMA) program, which included a special observing period that took place over West Africa in 2006, a major effort was devoted to monitor the atmosphere and its water cycle. The radiosonde network was upgraded and enhanced, and GPS receivers deployed. Among all sondes released in the atmosphere, a significant number were Vaisala RS80-A sondes, which revealed a significant dry bias relative to Vaisala RS92 (a maximum of 14% in the lower atmosphere, reaching 20% in the upper levels). This paper makes use of a simple but robust statistical approach to correct the bias. Comparisons against independent GPS data show that the bias is almost removed at night, whereas for daytime conditions, a weak dry bias (5%) still remains. The correction enhances CAPE by a factor of about 4 and, thus, becomes much more in line with expected values over the region. Numéro de notice : A2008-570 Affiliation des auteurs : LAREG+Ext (1991-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1175/2008JTECHA1103.1 Date de publication en ligne : 01/11/2008 En ligne : https://doi.org/10.1175/2008JTECHA1103.1 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103427
in Journal of Atmospheric and Oceanic Technology > vol 25 n° 11 (November 2008) . - pp 2152 - 2158[article]Galileo down to the millimeter: analyzing a GIOVE-A-B double difference / Christian Tiberius in Inside GNSS, vol 3 n° 6 (September 2008)
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Titre : Galileo down to the millimeter: analyzing a GIOVE-A-B double difference Type de document : Article/Communication Auteurs : Christian Tiberius, Auteur ; Hans van der Marel, Auteur ; Jean-Marie Sleewaegen, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : 5 p. ; pp 40 - 44 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] constellation Galileo
[Termes IGN] données Galileo
[Termes IGN] double différence
[Termes IGN] phase GNSS
[Termes IGN] résolution d'ambiguïté
[Termes IGN] traitement de données GNSSRésumé : (Editeur) With only two spacecraft in orbit for the Galileo constellation that will eventually have 30 satellites, having enough observation time to track and analyze the new signals can pose a challenge. Using a short baseline set-up and a late-night session, however, these authors were able to collect simultaneous measurements from both satellites, perform a double-difference resolution of the carrier phase cycle ambiguity, and assess the measurement noise. Copyright Gibbons Media & Research LLC Numéro de notice : A2008-680 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33532
in Inside GNSS > vol 3 n° 6 (September 2008) . - 5 p. ; pp 40 - 44[article]Documents numériques
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Galileo down to the millimeter ... - pdf éditeurAdobe Acrobat PDF MBOC vs BOC (1,1): multipath comparison based on GIOVE-B data / A. Simsky in Inside GNSS, vol 3 n° 6 (September 2008)
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Titre : MBOC vs BOC (1,1): multipath comparison based on GIOVE-B data Type de document : Article/Communication Auteurs : A. Simsky, Auteur ; D. Mertens, Auteur ; M. Hollreiser, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : 5 p. ; pp 36 - 40 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] correction du trajet multiple
[Termes IGN] données Galileo
[Termes IGN] modulation du signal
[Termes IGN] phase
[Termes IGN] trajet multipleRésumé : (Editeur) In 2004 the United States and the European Union signed a ground-breaking agreement to provide common, interoperable signals for civil users of GPS and Galileo: a binary offset carrier (BOC) modulation with a 1.023 MHz sub-carrier frequency and a code rate of 1.023 mega-chips per second — BOC (1,1) — centered at 1575.42 MHz. Subsequent discussions by a US/EU technical working group produced what was considered — not without dissent — to be an even better signal structure: a multiplex BOC. With the GIOVE-B satellite now in orbit and broadcasting the new signals, a team of researchers have evaluated the actual improvement in multipath mitigation by MBOC relative to BOC(1,1). Copyright Gibbons Media & Research LLC Numéro de notice : A2008-676 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33521
in Inside GNSS > vol 3 n° 6 (September 2008) . - 5 p. ; pp 36 - 40[article]Documents numériques
peut être téléchargé
MBOC vs BOC (1,1) ... - pdf éditeurAdobe Acrobat PDF Uplift and subsidence due to the 26 December 2004 Indonesian earthquake detected by SAR data / Marco Chini in International Journal of Remote Sensing IJRS, vol 29 n°13-14 (July 2008)PermalinkMulti-technique monitoring of ocean tide loading in Northern France / Muriel Llubes in Comptes rendus : Géoscience, vol 340 n° 6 (June 2010)PermalinkA compression format and tools for GNSS observation data / Yuki Hatanaka in Bulletin of the Geographical survey institute, vol 55 (March 2008)PermalinkFast error analysis of continuous GPS observations / M. Bos in Journal of geodesy, vol 82 n° 3 (March 2008)PermalinkOn the non-uniqueness of local quasi-geoids computed from terrestrial gravity anomalies / I. Prutkin in Journal of geodesy, vol 82 n° 3 (March 2008)PermalinkLa via Julia Augusta entre Menton et Nice / Jérôme Repetti in Géomatique expert, n° 61 (01/03/2008)PermalinkAssessment of water budgets computed from NWP models and observational datasets during AMMA-EOP / Olivier Bock (2008)PermalinkGPS composite clock analysis / James R. Wright in International Journal of Navigation and Observation, vol 2008 (01/01/2008)PermalinkLocal 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)Permalink