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The effect of tropospheric delay on GPS height differences along the Equator / J. Dodo in SaLIS Surveying and land information science, vol 68 n° 3 (September 2008)
[article]
Titre : The effect of tropospheric delay on GPS height differences along the Equator Type de document : Article/Communication Auteurs : J. Dodo, Auteur ; M. Kamarudin, Auteur ; M. Yahya, Auteur Année de publication : 2008 Article en page(s) : pp 145 - 154 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Nivellement
[Termes IGN] antenne GPS
[Termes IGN] correction du signal
[Termes IGN] équateur (géodésie)
[Termes IGN] erreur systématique
[Termes IGN] GPS en mode cinématique
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] Malaisie
[Termes IGN] nivellement par GPS
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] propagation troposphérique
[Termes IGN] zone équatorialeRésumé : (Auteur) The fundamental issue in GPS positioning is the ability to mitigate all the potential errors and biases in the system. The atmosphere related errors of ionosphere and troposphere constitute one of these potential errors. The tropospheric effect is much more pronounced at the equatorial region due to its hot and wet conditions. This significantly affects the GPS signal due to the variability of the refractive index, which in turn affects the accuracy of GPS positioning, especially in the height components. This paper presents a study conducted in Malaysia located at the equatorial region, to investigate the impact of tropospheric delay on GPS height variation. Five GPS reference stations forming part of the Malaysian real-time kinematic GPS network (MyRTKnet) in Johor were used. RINEX data from these stations were integrated with GPS and ground meteorological data observed from a GPS station located at the Universiti Teknologi Malaysia (UTM), at varying antenna heights for each session of observation in four campaigns with each campaign lasting for three days. A computer program called TROPO.exe was developed based on Saastamoinen tropospheric model. The result shows variations in the height component of GPS measurement with a maximum value of 119.100 cm and a minimum value of 37.990 cm. Similarly, the results show that the tropospheric delay is a distance-dependent error which varies with changes in meteorological condition. Furthermore, the results of simulated data show a decrease in tropospheric delay with increase in antenna height. Copyright SaLIS Numéro de notice : A2008-411 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83665
in SaLIS Surveying and land information science > vol 68 n° 3 (September 2008) . - pp 145 - 154[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 121-08031 RAB Revue Centre de documentation En réserve L003 Disponible Performance of GPS precise point positioning under conifer forest canopies / Erik Naesset in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 5 (May 2008)
[article]
Titre : Performance of GPS precise point positioning under conifer forest canopies Type de document : Article/Communication Auteurs : Erik Naesset, Auteur ; J.G. Gjevestad, Auteur Année de publication : 2008 Article en page(s) : pp 661 - 668 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] antenne GPS
[Termes IGN] forêt
[Termes IGN] GPS en mode différentiel
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] Pinophyta
[Termes IGN] positionnement par GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision du positionnement
[Termes IGN] troncRésumé : (Auteur) A 20-channel, dual-frequency GPS receiver collecting pseudorange and carrier phase observations was used as a stand-alone receiver to determine positional accuracy of 19 points under conifer tree canopies. The positions were determined utilizing precise satellite orbit and clock products from the International GNSS Service. The mean positional accuracy ranged from 0.27 to 0.88 m for an observation period of 120 minutes, and 0.95 to 3.48 m for 15 minutes. For the 15 minute observation period computed positions could not be found for 8 to 44 percent of the locations. Accuracy increased with decreasing forest stand density. Stand basal area (R2 = 0.11, p Numéro de notice : A2008-179 Affiliation des auteurs : non IGN Thématique : FORET/POSITIONNEMENT Nature : Article DOI : 10.14358/PERS.74.5.661 En ligne : https://doi.org/10.14358/PERS.74.5.661 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29174
in Photogrammetric Engineering & Remote Sensing, PERS > vol 74 n° 5 (May 2008) . - pp 661 - 668[article]Standards in practice: part 6 sensor web enablement / Huibert-Jan Lekkerkerk in Geoinformatics, vol 11 n° 2 (01/03/2008)
[article]
Titre : Standards in practice: part 6 sensor web enablement Type de document : Article/Communication Auteurs : Huibert-Jan Lekkerkerk, Auteur Année de publication : 2008 Article en page(s) : pp 22 - 23 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] antenne
[Termes IGN] géomatique web
[Termes IGN] géopositionnement
[Termes IGN] interface logicielle
[Termes IGN] interface web
[Termes IGN] Sensor Web Enablement
[Termes IGN] standard OGC
[Termes IGN] télécommunicationRésumé : (Auteur) Our world is full all kinds of sensors. And while the collection of sensor data has long been a matter of single organization using its own data, there is now a strong tendency to publish this data to the internet : examples are meteorological, water and air pollution data. In order to simplify the discovery and use such sensors, the Open Geospatial Consortium (OGC) has developed the Sensor Web Enablement framework (SWE) consistying of a set of standards that define how web-enabled sensors should communicate. Copyright GEOinformatics Numéro de notice : A2008-066 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29061
in Geoinformatics > vol 11 n° 2 (01/03/2008) . - pp 22 - 23[article]Voir aussiRéservation
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Code-barres Cote Support Localisation Section Disponibilité 262-08021 SL Revue Centre de documentation Revues en salle Disponible Modern radar systems / H. Meikle (2008)
Titre : Modern radar systems Type de document : Monographie Auteurs : H. Meikle, Auteur Mention d'édition : 2 Editeur : Londres, Washington : Artech House Année de publication : 2008 Importance : 701 p. Format : 22 x 29 cm ISBN/ISSN/EAN : 978-1-59693-242-5 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Télédétection
[Termes IGN] antenne radar
[Termes IGN] détecteur
[Termes IGN] écho radar
[Termes IGN] émetteur
[Termes IGN] filtrage du signal
[Termes IGN] géopositionnement
[Termes IGN] hyperfréquence
[Termes IGN] performance
[Termes IGN] polarisation
[Termes IGN] radar
[Termes IGN] récepteur radar
[Termes IGN] seuillage d'image
[Termes IGN] télédétection en hyperfréquence
[Termes IGN] traitement du signal
[Termes IGN] transformation de Fourier
[Termes IGN] transformation mathématiqueIndex. décimale : 35.22 Télédétection en hyperfréquence - Traitement d'image radar Résumé : (Editeur) This revised and updated edition offers professionals complete and current coverage of the subject, including new material on critical aspects such as accuracy, resolution, and convolution and correlation. The book features more than 540 illustrations that offer a greater understanding of various waveforms, and other two- and three-dimensional functions, to help engineers more accurately analyze radar system performance. The effects of pulse shaping on transmitter stability and spectra are discussed - a topic that is becoming more and more important to today's engineers. Radar practitioners get a number of critical atmospheric models to help them with their challenging work. Each chapter ends with a performance section, showing the effect of that particular aspect on the complete radar system budget for range, accuracy, and stability. Note de contenu : Chapitre 1 - The radar and its ground environment
Chapitre 2 - Usual and Unusual Concepts
Chapitre 3 - Transmitters
Chapitre 4 - Microwave waveguide and transmission line system
Chapitre 5 - Antennas
Chapitre 6 - Factors outside the radar : propagation, scattering and clutter
Chapitre 7 - Receivers
Chapitre 8 - Matched and matching filters
Chapitre 9 - Detectors
Chapitre 10 - Analogue-to-digital conversion
Chapitre 11 - Signal processing
Chapitre 12 - Threshold and detection
Chapitre 13 - Determination of position
Chapitre 14 - Performance
Chapitre 15 - Transforms
AnnexesNuméro de notice : 20108 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62917 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 20108-01 35.22 Livre Centre de documentation Télédétection Disponible Generation of a consistent absolute phase center correction model for GPS receiver and satellite antennas / Ralf Schmid in Journal of geodesy, vol 81 n° 12 (December 2007)
[article]
Titre : Generation of a consistent absolute phase center correction model for GPS receiver and satellite antennas Type de document : Article/Communication Auteurs : Ralf Schmid, Auteur ; Peter Steigenberger, Auteur ; et al., Auteur Année de publication : 2007 Article en page(s) : pp 781 - 798 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GPS
[Termes IGN] centre de phase
[Termes IGN] correction du signal
[Termes IGN] données GPS
[Termes IGN] jeu de données
[Termes IGN] phase GPS
[Termes IGN] récepteur GPSRésumé : (Auteur) The development and numerical values of the new absolute phase-center correction model for GPS receiver and satellite antennas, as adopted by the International GNSS (global navigation satellite systems) Service, are presented. Fixing absolute receiver antenna phase-center corrections to robot-based calibrations, the GeoForschungsZentrum Potsdam (GFZ) and the Technische Universität München reprocessed more than 10 years of GPS data in order to generate a consistent set of nadir-dependent phase-center variations (PCVs) and offsets in the z-direction pointing toward the Earth for all GPS satellites in orbit during that period. The agreement between the two solutions estimated by independent software packages is better than 1 mm for the PCVs and about 4 cm for the z-offsets. In addition, the long time-series facilitates the study of correlations of the satellite antenna corrections with several other parameters such as the global terrestrial scale or the orientation of the orbital planes with respect to the Sun. Finally, completely reprocessed GPS solutions using different phase-center correction models demonstrate the benefits from switching from relative to absolute antenna phase-center corrections. For example, tropospheric zenith delay biases between GPS and very long baseline interferometry (VLBI), as well as the drift of the terrestrial scale, are reduced and the GPS orbit consistency is improved. Copyright Springer Numéro de notice : A2007-525 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-007-0148-y En ligne : https://doi.org/10.1007/s00190-007-0148-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28888
in Journal of geodesy > vol 81 n° 12 (December 2007) . - pp 781 - 798[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-07101 RAB Revue Centre de documentation En réserve L003 Disponible 266-07102 RAB Revue Centre de documentation En réserve L003 Disponible GPS des villes, GPS des champs / Anonyme in Géomatique expert, n° 58 (01/09/2007)PermalinkDORIS satellite phase center determination and consequences on the derived scale of the Terrestrial Reference Frame / Pascal Willis in Advances in space research, vol 39 n° 10 (May 2007)PermalinkMeet GIOVE-A: Galileo's first test satellite / E. Rooney in GPS world, vol 18 n° 5 (May 2007)PermalinkAnalysis of DORIS range-rate residuals for TOPEX/Poseidon, Jason, Envisat and SPOT / Eelco Doornbos in Acta Astronautica, vol 60 n° 8-9 (April - May 2007)PermalinkNouvelles technologies : quelles (r)évolutions pour la topographie ? / Tania Landes in XYZ, n° 110 (mars - mai 2007)PermalinkStochastic models for GPS positioning: an empirical approach / Rodrigo Figueiredo Leandro in GPS world, vol 18 n° 2 (February 2007)PermalinkPermalinkPractical satellite navigation: part 7 receiver installation / Huibert-Jan Lekkerkerk in Geoinformatics, vol 9 n° 7 (01/11/2006)PermalinkPhase wind-up analysis: assessing real-time kinematic performance / D. Kim in GPS world, vol 17 n° 9 (September 2006)PermalinkPractical satellite navigation: Part 6 base station installation / Huibert-Jan Lekkerkerk in Geoinformatics, vol 9 n° 6 (01/09/2006)Permalink