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Titre : Evaluation de la qualité du modèle de covariance d’un champ aléatoire Type de document : Mémoire Auteurs : Samuel Nahmani , Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2006 Importance : 69 p. Note générale : bibliographie
Mémoire Master Photogrammétrie Positionnement Mesure des Déformations et Cycle d’Ingénieur ENSG 3ème annéeLangues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] algorithme génétique
[Termes IGN] champ aléatoire de Markov
[Termes IGN] covariance
[Termes IGN] erreur systématique
[Termes IGN] krigeage
[Termes IGN] méthode des moindres carrés
[Termes IGN] méthode du maximum de vraisemblance (estimation)Note de contenu : Introduction
1 Géostatistique classique dans un cadre stationnaire
1.1 Approche stochastique
1.2 Krigeage simple (collocation)
1.3 Exemple d’utilisation de la collocation en gravimétrie
2 Estimation des paramètres de la fonction de covariance
2.1 Analyse covariographique
2.2 Estimation par maximum de vraisemblance
3 Evaluation de la qualité d’un modèle de covariance estimé
3.1 Problématique
3.2 Seconde approche basée sur des tests statistiques
3.3 Résultats
4 Impact de la qualité d’un modèle de covariance estimé sur la prévision des erreurs
4.1 Problématique
4.2 Protocole expérimental
4.3 Résultats
ConclusionNuméro de notice : 17770 Affiliation des auteurs : IGN (1940-2011) Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Mémoire PPMD Organisme de stage : LAREG (IGN) Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103417 Documents numériques
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Titre : Precise relative positioning of formation flying spacecraft using GPS Type de document : Thèse/HDR Auteurs : Remco Kroes, Auteur Editeur : Delft : Netherlands Geodetic Commission NGC Année de publication : 2006 Collection : Netherlands Geodetic Commission Publications on Geodesy, ISSN 0165-1706 num. 61 Importance : 163 p. Format : 17 x 24 cm ISBN/ISSN/EAN : 978-90-6132-296-2 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] ambiguïté entière
[Termes IGN] compensation Lambda
[Termes IGN] erreur systématique
[Termes IGN] filtre de Kalman
[Termes IGN] GPS-INS
[Termes IGN] GRACE
[Termes IGN] image TerraSAR-X
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] méthode des moindres carrés
[Termes IGN] navigation spatiale
[Termes IGN] orbitographie par GNSS
[Termes IGN] positionnement différentiel
[Termes IGN] positionnement par GPS
[Termes IGN] précision millimétrique
[Termes IGN] qualité des données
[Termes IGN] résolution d'ambiguïté
[Termes IGN] signal GPSIndex. décimale : 30.70 Navigation et positionnement Résumé : (Auteur) Spacecraft formation flying is currently considered as a key technology for advanced space missions. Compared to large individual spacecraft, the distribution of Sensor systems amongst multiple platforms offers improved flexibility and redundancy, shorter times to mission and the prospect of being more cost effective. Besides these advantages, satellite formations in low Earth orbit provide advanced science opportunities that cannot, or not easily, be realized with single spacecraft. One of the fundamental issues of spacecraft formation flying is the determination of the relative state (position and velocity) between the satellite vehicles within the formation. Knowledge of these relative states in (near) real-time is important for operational aspects. In addition, some of the scientific applications, such as high resolution interferometry, require an accurate post-facto knowledge of these States. The goal of this dissertation is therefore to develop, implement and test a method for high precise post-facto relative positioning of formation flying spacecraft, using GPS observation data. The need for such a methodology comes from scientific satellite formation flying missions that are currently being planned. A good example here is the Synthetic Aperture Radar (SAR) interferometry formation consisting of the TerraSAR-X and TanDEM-X satellites. The primary mission objective here requires the relative position to be known within a 2 mm precision (1-dimensional).
GPS receivers are often considered as the primary instruments for precise relative navigation in future satellite formation flying missions. As is commonly known, precise relative positioning between GPS receivers in geodetic networks is exercised on a routine basis. Furthermore, GPS receivers are already frequently used onboard satellites to perform all kinds of navigational tasks, are suitable for real-time applications and provide measurements with a 3-dimensional nature.
Previous studies carried out in this research area focussed on the real-time or operational aspects, and all used GPS data obtained from software or hardware-in-the-loop simulations. This dissertation clearly distinguishes itself due to the fact that the developed methodology has been tested using real-world GPS data from the GRACE mission, which in addition also provides a precise way to validate the obtained results by means of the GRACE K/Ka-Band Ranging System (KBR) observations.
One of the key aspects of any GPS positioning application is the quality of the observation data used. To this extent an in-flight performance analysis of the used GRACE (and CHAMP) GPS data bas been carried out. The results show that the GRACE GPS pseudorange observations, on the individual frequencies, are subject to systematic errors in the order of 10-15 cm. Furthermore, an assessment of the noise of both the GPS pseudorange and carrier phase data demonstrates that the noise of the GRACE B observation data is significantly lower.
When using GPS for precise relative spacecraft positioning, the trajectory or orbit of one of the spacecraft, serving as the reference, has to be known to the best possible extent. In order to facilitate this, a total of three precise orbit determination strategies, using undifferenced ionosphere free GPS pseudorange and carrier phase observations, have been implemented and tested. They comprise a kinematic and reduced dynamic batch LSQ estimation method, as well as an extended Kalman filter/smoother (EKF), that also form the conceptual basis for the relative spacecraft positioning strategies. Each of the precise orbit determination concepts has been tested using GPS data from the CHAMP and GRACE missions. The reduced dynamic batch LSQ orbits were validated with Satellite Laser Ranging data, where the residuals showed an RMS of 3-4 cm.
Out of a total of four possible processing strategies that have been identified for relative spacecraft positioning, only an extended Kalman filter/smoother has proven to work satisfactorily when tested on the real-world GRACE GPS data. The EKF processes single difference GPS pseudorange and carrier phase observations and uses (pseudo) relative spacecraft dynamics to propagate the relative satellite state over the observation epochs. Despite its single difference parametrization the EKF can still resolve and incorporate the integer double difference carrier phase ambiguities, which is commonly regarded as, and has proven to be in this dissertation, the key to precise GPS based relative positioning. Estimation of the integer ambiguities is accomplished by the well known Least Squares Ambiguity Decorrelation Adjustment (LAMBDA) method. Due to the presence of systematic errors in the GRACE GPS data, a relatively conservative validation of the estimated integer ambiguity parameters was found to be required prior to their incorporation in the filter. When validating the daily ambiguity fixed GRACE relative position solutions from the EKF with the KBR observations, it has been shown that an actual overall relative position precision of 0.9 mm (1-dimensional) over a 101 day data arc is achieved. This dissertation is the first that proves that such precision can be truly obtained for real-world relative spacecraft positioning applications.Note de contenu : 1 Introduction
1.1 Spacecraft formation flying using GPS
1.2 Research objective and motivation
1.3 The CHAMP and GRACE satellite missions
1.4 Outline
2 GPS observations
2.1 Observation types
2.3 Linear data combinations
2.4 Linearization for positioning
2.5 Relative positioning models
2.6 GPS data quality
3 Precise orbit determination
3.1 GPS orbit and clock products
3.2 Reference frame transformations.
3.3 Kinematic orbit determination.
3.4 Reduced dynamic orbit determination
3.5 GHOST toolkit
3.6 POD results
4 Relative spacecraft positioning
4.1 Integer ambiguity resolution
4.2 Proposed processing strategies
4.3 Details of the extended Kalman filter
4.4 Extended Kalman filter results.
4.5 Some words on
5 Conclusions and outlookNuméro de notice : 15179 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : sans En ligne : https://www.ncgeo.nl/downloads/61Kroes.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55089 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15179-01 30.70 Livre Centre de documentation Géodésie Disponible 15179-02 30.70 Livre Centre de documentation Géodésie Disponible Shuttle Radar Topography Mission elevation data error and its relationship to land cover / A. Shortridge in Cartography and Geographic Information Science, vol 33 n° 1 (January 2006)
[article]
Titre : Shuttle Radar Topography Mission elevation data error and its relationship to land cover Type de document : Article/Communication Auteurs : A. Shortridge, Auteur Année de publication : 2006 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse comparative
[Termes IGN] données altimétriques
[Termes IGN] erreur systématique
[Termes IGN] image radar moirée
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] MNS SRTM
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrain
[Termes IGN] occupation du sol
[Termes IGN] précision altimétrique
[Termes IGN] qualité des donnéesRésumé : (Auteur) The Shuttle Radar Topography Mission (SRTM) has resulted in the construction of the first publicly available near-global high resolution digital elevation model (DEM). The utility of this DEM, as for any geospatial data set, is a function of its quality. This paper is concerned with the assessment of SRTM accuracy and its relationship to land cover. Two methods-one raster-based and one point-based-are compared to match "finished" three-arc-second SRTM data to high precision, high accuracy surveyed elevations, as well as a corresponding DEM from the USGS National Elevation Dataset (NED). Differences between the two methodologies were not found to be significant. Error for the study site is substantially less than the mission objective, but substantially more than that for the NED. Significant overestimation of actual elevations pervades the SRTM DEM, and the overestimation is significantly higher in forested areas. This systematic error has implications both for applications employing SRTM data and for research on elevation data error modeling. Copyright CaGISociety Numéro de notice : A2006-206 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1559/152304006777323172 En ligne : https://doi.org/10.1559/152304006777323172 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27933
in Cartography and Geographic Information Science > vol 33 n° 1 (January 2006)[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-06011 RAB Revue Centre de documentation En réserve L003 Disponible Lidar validation using GIS : a case study comparison between two Lidar collection methods / T.L. Webster in Geocarto international, vol 20 n° 4 (December 2005 - February 2006)
[article]
Titre : Lidar validation using GIS : a case study comparison between two Lidar collection methods Type de document : Article/Communication Auteurs : T.L. Webster, Auteur Année de publication : 2005 Article en page(s) : pp 11 - 19 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse comparative
[Termes IGN] données lidar
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] modèle numérique de surface
[Termes IGN] Nouvelle-Ecosse (Canada)
[Termes IGN] plateforme logicielle
[Termes IGN] point de vérification
[Termes IGN] système d'exploitation
[Termes IGN] système d'information géographique
[Termes IGN] télémètre laser à balayage
[Termes IGN] télémétrie laser aéroportéRésumé : (Auteur) In the summer of 2000, the Annapolis Valley of Nova Scotia, Canada was selected for a high-resolution elevation survey utilizing LIDAR (Light Detection And Ranging). Two different LIDAR systems were used to acquire data for the area. The vertical accuracy specification for the survey called for heights to be within an average of 15 cm of measured GPS heights and 95% of the data to be within 30 cm. Prior to the application of these data to geoscientific problems, extensive validation procedures were employed. High precision GPS and traditional surveys were conducted to collect height validation checkpoints. Two validation methods were developed in a GIS environment that involved comparing the checkpoints to the original LIDAR points and to an interpolated "bald earth " DEM. A systematic height error between flight lines for one of the LIDAR methods was detected that related to the calibration procedures used in the survey. This study highlights the differences between laser systems, calibration and deployment methodologies and emphasizes the necessity for independent validation data. Numéro de notice : A2005-552 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040508542359 Date de publication en ligne : 02/01/2008 En ligne : https://doi.org/10.1080/10106040508542359 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27688
in Geocarto international > vol 20 n° 4 (December 2005 - February 2006) . - pp 11 - 19[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-05041 RAB Revue Centre de documentation En réserve L003 Disponible Effects of laser beam alignment tolerance on lidar accuracy / D. Latypov in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 6 (November 2005)
[article]
Titre : Effects of laser beam alignment tolerance on lidar accuracy Type de document : Article/Communication Auteurs : D. Latypov, Auteur Année de publication : 2005 Article en page(s) : pp 361 - 368 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] données lidar
[Termes IGN] erreur systématique
[Termes IGN] étalonnage géométrique
[Termes IGN] faisceau
[Termes IGN] Lidar
[Termes IGN] orientation du capteur
[Termes IGN] plan de vol
[Termes IGN] point d'appui
[Termes IGN] télémétrie laser aéroportéRésumé : (Auteur) One of the major lidar error sources not yet analysed in the literature is the tolerance of the laser beam alignment with respect to the scanning mirror. In this paper, the problem of quantifying these errors is solved for rotating polygon mirror type lidar systems. An arbitrary deviation of the beam from its design direction -the vector of beam misalignment- can be described by two independent parameters. We choose these as horizontal and vertical components of the misalignment vector in the body frame. Either component affects both, horizontal and vertical lidar accuracy. Horizontal lidar errors appear as scan line distortions-along and across track shifts, rotations and scaling. It is shown that the horizontal component of misalignment results in a scan line first being shifted across the track and then rotated around the vertical at the new center of the scan line. Resulting vertical lidar error, being a linear function of the scan angle, is similar to that produced by a roll bias. The vertical component of the beam misalignment causes scan line scaling and an along track shift. The corresponding vertical error is quadratic with respect to the scan angle. The magnitude of these effects is significant even at tight alignment tolerances and cannot be realistically accounted for in the conventional calibration model, which includes only range, attitude and GPS biases. Therefore, in order to attain better accuracy, this model must be expanded to include the beam misalignment parameters as well. Addition of new parameters into the model raises a question of whether they can be reliably solved for. To give a positive answer to this question, a calibration method must utilize not only ground control information, which is typically very limited, but also the relative accuracy information from the overlapping flight lines. Copyright ISPRS Numéro de notice : A2005-491 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2005.09.002 En ligne : https://doi.org/10.1016/j.isprsjprs.2005.09.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27627
in ISPRS Journal of photogrammetry and remote sensing > vol 59 n° 6 (November 2005) . - pp 361 - 368[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-05041 SL Revue Centre de documentation Revues en salle Disponible Stratified sampling of satellite images with a systematic grid of points / F.J. Gallego in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 6 (November 2005)PermalinkBias-compensated RPCs [rational polynomial coefficient] for sensor orientation of high-resolution satellite imagery / Clive Simpson Fraser in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 8 (August 2005)PermalinkQuality assessment of digital surface models generated from Ikonos imagery / J. Poon in Photogrammetric record, vol 20 n° 110 (June - August 2005)PermalinkInfluence of system calibration on direct sensor orientation / N. Yastikli in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 5 (May 2005)PermalinkInteroperability on time: GPS-Galileo offset will bias position / A. Moudrak in GPS world, vol 16 n° 3 (March 2005)PermalinkQuality assessment and improvement of temporally composite products of remote sensed imagery by combination of Vegetation 1 and 2 images / Olivier Hagolle in Remote sensing of environment, vol 94 n° 2 (30/01/2005)PermalinkApports des techniques de filtrage non linéaire pour la navigation avec les systèmes de navigation inertiels et le GPS / A. Giremus (2005)PermalinkAutomatisierte Auswertung und Kalibrierung von scannenden Messsystemen mit tachymetrischem Messprinzip / A. Rietdorf (2005)PermalinkPermalinkEvaluation de la précision globale d'un positionnement GPS en réseau / F. Molle (2005)PermalinkLandsat-7 ETM+ on-orbit reflective-band radiometric characterization / L. Scaramuzza in IEEE Transactions on geoscience and remote sensing, vol 42 n° 12 (December 2004)PermalinkCalibrating geodetic instruments: standards for calibration and testing / P. Savvaidis in Geoinformatics, vol 7 n° 7 (01/11/2004)PermalinkAccuracy assessment of Quickbird stereo imagery / M. Noguchi in Photogrammetric record, vol 19 n° 106 (June - August 2004)PermalinkDTM generation from Ikonos in-track stereo images using a 3D physical model / Thierry Toutin in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 6 (June 2004)PermalinkValidation and calibration of Canada-wide coarse-resolution satellite burned-area maps / R.H. Fraser in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 4 (April 2004)PermalinkCaractérisation d'erreurs sur un MNT en fonction de zones morphologiques / Frédéric Rousseaux in Géomatique expert, n° 32 (01/03/2004)PermalinkManual of photogrammetry, fifth edition / J. Chris Mcglone (2004)PermalinkPermalinkAbsolute calibration of Jason-1 and TOPEX/Poseidon altimeters in Corsica / Pascal Bonnefond in Marine geodesy, vol 26 n°3-4 (July - December 2003)PermalinkSynergetic fusion of GPS and photogrammetrically generated elevation models / Jon P. Mills in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 4 (April 2003)Permalink