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Titre : Multi-GNSS Hybridization for Precise Positioning Type de document : Thèse/HDR Auteurs : Georgia Katsigianni, Auteur ; Félix Perosanz, Directeur de thèse ; Sylvain Loyer, Directeur de thèse Editeur : Toulouse : Université de Toulouse 3 Paul Sabatier Année de publication : 2019 Importance : 143 p. Format : 21 x 30 cm Note générale : Thèse en vue de l'obtention du Doctorat de l'Université de Toulouse 3 Paul Sabatier, Spécialité Sciences de la Terre et des Planètes Solides Langues : Anglais (eng) Descripteur : [Termes IGN] données Galileo
[Termes IGN] données GPS
[Termes IGN] orbitographie
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Vedettes matières IGN] Traitement de données GNSSIndex. décimale : THESE Thèses et HDR Résumé : (auteur) GNSS are widely used for precise positioning applications of geosciences and especially space geodesy. So far, mainly the existing GPS was extensively used for scientific applications. With the arrival of the new European Galileo system it became imperative to include the new system in the studies and check the new capabilities that it will bring as a system alone and as combined together with the others in a Multi-GNSS processing. The CNES/CLS analysis center of the IGS is weekly calculating GNSS (GPS, GLONASS and Galileo) products that can be taken from any kind of user to perform precise positioning. A way to achieve the best accuracy possible is to resolve the unknown integer ambiguities of the phase measurements. Up until now, the CNES/CLS was performing ambiguity resolution to the GPS system using the zero-difference method. In this way they are able to deliver precise satellite orbits and precise clock products with phase fixed ambiguities. The goal of this work was to implement and validate if the method can be also applied for the Galileo system. The method applied from the CNES/CLS is consisting of two further steps. The first one is the resolution of the Wide-Lane ambiguities. The Galileo Wide-Lane satellite biases have been proven to be stable over long periods of time. In addition, there is homogeneity in the way they are observed from different types of receivers. These findings were used and the Wide-Lane biases were successfully resolved with nearly 100% success rate percentage. The second step of zero-difference method is the Narrow-Lane ambiguity resolution. This step was executed for the Galileo system together with the GPS system in a Multi-GNSS Precise Orbit Determination processing. Galileo ambiguity fixing success percentage is around 93%, nearly similar to the one of the GPS system. The integer property of the Galileo phase clocks is demonstrated. Both orbit overlaps and orbit validation using SLR validation methods showed that ambiguity resolution improves mainly in the normal and the along track direction. Galileo orbit overlaps in 3D RMS showed an improvement of around 50%, from around 7 cm to 3.5 cm. The results of this work were used by the CNES/CLS IGS AC that has announced the delivery of weekly Galileo precise orbits, clocks and Wide-Lane satellite biases. A new method is also introduced on how to compare ambiguity resolution results for a common overlapping period. This method is also used to speculate the agreement and the disagreement between two different daily solutions. Finally, it was examined the post-processed kinematic PPP and PPP-AR using Galileo-only, GPSonly and Multi-GNSS (GPS + Galileo) constellations. The interest was to validate the accuracy for each GNSS system individually but also of their combination. Results showed that Galileoonly positioning accuracy is nearly at the same level of accuracy as GPS-only. The use of Galileo system improves the performance of the GPS positioning giving mm level repeatability. The contribution of Galileo ameliorates the positioning accuracy around 30% in all directions(comparison GPS PPP-AR and Multi-GNSS PPP-AR). This proved that the Galileo constellation together with GPS will give improved precise positioning with respect to the current GPS-only.
All these are indications that the Galileo system will contribute to precise positioning required by geoscience applications through a Multi-GNSS (GPS + Galileo) solution.Note de contenu : 1- Introduction
2- GNSS in science
3- GNSS measurements
4- Galileo Wide-Lane AR
5- Galileo Narrow-Lane AR
6- Precise Point Positioning
7- Conclusions and SuggestionsNuméro de notice : 28511 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse française Note de thèse : Thèse de Doctorat : Sciences de la Terre et des Planètes Solides : Toulouse 3 : 2019 Organisme de stage : Geosciences Environnement Toulouse nature-HAL : Thèse DOI : sans En ligne : http://www.theses.fr/2019TOU30209 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97142 Multimodal scene understanding: algorithms, applications and deep learning, ch. 8. Multimodal localization for embedded systems: a survey / Imane Salhi (2019)
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Titre de série : Multimodal scene understanding: algorithms, applications and deep learning, ch. 8 Titre : Multimodal localization for embedded systems: a survey Type de document : Chapitre/Contribution Auteurs : Imane Salhi , Auteur ; Martyna Poreba
, Auteur ; Erwan Piriou, Auteur ; Valérie Gouet-Brunet
, Auteur ; Maroun Ojail, Auteur
Editeur : Londres, New York : Academic Press Année de publication : 2019 Importance : pp 199 - 278 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] compréhension de l'image
[Termes IGN] fusion de données
[Termes IGN] géopositionnement
[Termes IGN] instrument embarqué
[Termes IGN] navigation automobile
[Termes IGN] navigation pédestre
[Termes IGN] réalité mixteRésumé : (Auteur) Localization by jointly exploiting multimodal information, like cameras, inertial measurement units (IMU), and global navigation satellite system (GNSS) data, is an active key research topic for autonomous embedded systems such as smart glasses or drones. These systems have become topical for acquisition, modeling, and interpretation for scene understanding. The exploitation of different sensor types improves the robustness of the localization, e.g. by merging the accuracy of one sensor with the reactivity of another one in a flexible manner. This chapter presents a survey of the existing multimodal techniques dedicated to the localization of autonomous embedded systems. Both the algorithmic and the hardware architecture sides are investigated in order to provide a global overview of the key elements to be considered when designing these embedded systems. Several applications in different domains (e.g. localization for mapping, pedestrian localization, automotive navigation and mixed reality) are presented to illustrate the importance of such systems nowadays in scene understanding. Numéro de notice : H2019-001 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Chapître / contribution nature-HAL : ChOuvrScient DOI : 10.1016/B978-0-12-817358-9.00014-7 Date de publication en ligne : 02/08/2019 En ligne : https://doi.org/10.1016/B978-0-12-817358-9.00014-7 Format de la ressource électronique : URL chapitre Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93300 Objets et relations spatiales composites et prise en compte du vague pour interpréter un référencement spatial indirect / Mattia Bunel in Revue internationale de géomatique, vol 29 n° 1 (janvier - mars 2019)
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Titre : Objets et relations spatiales composites et prise en compte du vague pour interpréter un référencement spatial indirect Type de document : Article/Communication Auteurs : Mattia Bunel , Auteur ; Ana-Maria Olteanu-Raimond
, Auteur ; Cécile Duchêne
, Auteur
Année de publication : 2019 Projets : CHOUCAS / Olteanu-Raimond, Ana-Maria Article en page(s) : pp 81 - 106 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] montagne
[Termes IGN] objet flou
[Termes IGN] positionnement absolu
[Termes IGN] référentiel spatial
[Termes IGN] relation spatiale
[Termes IGN] secours d'urgenceRésumé : (Auteur) Cet article propose une méthodologie destinée à transformer une description de position exprimée dans un référentiel indirect en une position absolue dans un référentiel direct. Cette problématique nécessite une formalisation des éléments de localisation relatifs, ici sous la forme d’un modèle en triplets, utilisé ensuite comme base de référencement, et un questionnement sur la prise en compte de l’imperfection du langage naturel dans le processus de modélisation. Nous proposons de faire appel aux objets spatiaux flous et nous comparons leurs implémentations afin d’identifier l’approche la plus adaptée au contexte du secours en montagne. Numéro de notice : A2019-571 Affiliation des auteurs : LASTIG COGIT (2012-2019) Thématique : GEOMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3166/rig.2019.00075 Date de publication en ligne : 23/12/2019 En ligne : https://doi.org/10.3166/rig.2019.00075 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94442
in Revue internationale de géomatique > vol 29 n° 1 (janvier - mars 2019) . - pp 81 - 106[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 047-2019011 SL Revue Centre de documentation Revues en salle Disponible On constrained integrated total Kalman filter for integrated direct geo-referencing / Vahid Mahboub in Survey review, vol 51 n° 364 (January 2019)
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Titre : On constrained integrated total Kalman filter for integrated direct geo-referencing Type de document : Article/Communication Auteurs : Vahid Mahboub, Auteur ; Mohammad Saadatseresht, Auteur ; Alireza A. Ardalan, Auteur Année de publication : 2019 Article en page(s) : pp 26 - 34 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] filtrage du bruit
[Termes IGN] filtre de Kalman
[Termes IGN] géoréférencement direct
[Termes IGN] GPS-INS
[Termes IGN] invariant
[Termes IGN] matrice de covariance
[Termes IGN] modèle dynamiqueRésumé : (Auteur) A constrained integrated total Kalman filter algorithm is developed. It considers a quadratic constraint which may appear in some problems of integrated direct geo-referencing in particular when INS data is used as system equations of a Kalman filter algorithm. In such a case one encounters with a dynamic errors-in-variables (DEIV) model for system equations, although DEIV model has been already considered for equations of the Kalman filter algorithm and a solution namely integrated total Kalman filter (ITKF) has been given to it. Also this algorithm can be simplified to unconstraint case which is useful for some problems. It considers DEIV model for both observation equations and system equations of the Kalman filter algorithm. The predicted residuals for all variables including the random noise at the first epoch, the observational noise, the random system noise and the corresponding noise of two coefficient matrixes (in the system equations and the observation equations) besides the variance matrix of the unknown parameters are obtained. In two numerical examples, integrated direct geo-referencing problem is solved for a GPS-INS system. Numéro de notice : A2019-186 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2017.1341736 Date de publication en ligne : 30/06/2017 En ligne : https://doi.org/10.1080/00396265.2017.1341736 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92617
in Survey review > vol 51 n° 364 (January 2019) . - pp 26 - 34[article]Optimisation of GNSS networks, considering baseline correlations / M. Amin Alizadeh-Khameneh in Survey review, vol 51 n° 364 (January 2019)
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Titre : Optimisation of GNSS networks, considering baseline correlations Type de document : Article/Communication Auteurs : M. Amin Alizadeh-Khameneh, Auteur ; Lars E. Sjöberg, Auteur ; Anna B. O. Jensen, Auteur Année de publication : 2019 Article en page(s) : pp 35 - 42 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] corrélation
[Termes IGN] données GNSS
[Termes IGN] double différence
[Termes IGN] ligne de base
[Termes IGN] optimisation (mathématiques)
[Termes IGN] réseau géodésique local
[Termes IGN] SuèdeRésumé : (Auteur) By considering global navigation satellite system (GNSS) observations, one can perform optimisation according to some pre-defined criteria and come up with the best location of receivers and optimum number of baselines. In practice, it is quite common to neglect the effect of correlations between baselines, and instead assume single-baseline-adjusted data in the optimisation procedure. However, in each session of observation, usually more than two receivers are simultaneously taking data from a number of common GNSS satellites, implying that the single- or double-difference observations are correlated. Our study designs an optimal observation plan for a GPS network in Skåne in southern Sweden, with the aim of determining possible displacements. Assuming three receivers in each session of observations leads to correlation between the GPS baselines, and consequently a fully populated weight matrix for each session of observation. A bi-objective optimisation model of precision and reliability is chosen to optimise the variance factor of each session, and eventually, design an observation plan. It is shown in this study that observing six out of ten possible sessions is sufficient to enable the network to detect a 5 mm displacement at each station. Assuming that the double-difference phase observations are uncorrelated changes the observation plan by retaining two more sessions. However, defining the weight matrix based on the double-difference observations requires the correlations to be taken into account, and neglecting them leads to incorrect results. Numéro de notice : A2019-187 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Numéro de périodique nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2017.1342896 Date de publication en ligne : 26/06/2017 En ligne : https://doi.org/10.1080/00396265.2017.1342896 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92618
in Survey review > vol 51 n° 364 (January 2019) . - pp 35 - 42[article]Quality assessment of CNES real-time ionospheric products / Zhixi Nie in GPS solutions, vol 23 n° 1 (January 2019)
PermalinkReal-time capturing of seismic waveforms using high-rate BDS, GPS and GLONASS observations: the 2017 Mw 6.5 Jiuzhaigou earthquake in China / Xingxing Li in GPS solutions, vol 23 n° 1 (January 2019)
PermalinkPermalinkRTK and PPP-RTK using smartphones: From short-baseline to long-baseline applications / Francesco Darugna (2019)
PermalinkSystème de positionnement par satellite [support de formation dans le cadre des journées REFMAR 2019] / Thomas Donal (2019)
PermalinkTrilateration approaches for seamless out-/indoor GNSS and Wi-Fi smartphone positioning / Guenther Retscher in Journal of applied geodesy, vol 13 n° 1 (January 2019)
PermalinkUndifferenced zenith tropospheric modeling and its application in fast ambiguity recovery for long-range network RTK reference stations / Dezhong Chen in GPS solutions, vol 23 n° 1 (January 2019)
PermalinkValidating and comparing GNSS antenna calibrations / Ulla Kallio in Journal of geodesy, vol 93 n° 1 (January 2019)
PermalinkEnhanced local ionosphere model for multi-constellations single frequency precise point positioning applications: Egyptian case study / Emad El Manaily in Artificial satellites, vol 53 n° 4 (December 2018)
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PermalinkEtude de faisabilité et choix optimal d'une station RIMS d'EGNOS en Algérie / Tabti Lahouaria in XYZ, n° 157 (décembre 2018 - février 2019)
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