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Titre : Optimal GPS/GALILEO GBAS methodologies with an application to troposphere Type de document : Thèse/HDR Auteurs : Alize Guilbert, Directeur de thèse ; Christophe Macabiau, Directeur de thèse Editeur : Toulouse : Université de Toulouse Année de publication : 2016 Importance : 301 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse en vue de l'obtention du Doctorat de l'Université de Toulouse, spécialité :
Signal, Image, Acoustique et OptimisationLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] aviation civile
[Termes IGN] constellation Galileo
[Termes IGN] constellation GLONASS
[Termes IGN] constellation GPS
[Termes IGN] correction troposphérique
[Termes IGN] données GPS
[Termes IGN] erreur de positionnement
[Termes IGN] gradient de troposphère
[Termes IGN] modèle météorologique
[Termes IGN] positionnement par GNSS
[Termes IGN] retard troposphérique
[Termes IGN] système d'extension au solIndex. décimale : THESE Thèses et HDR Résumé : (auteur) In the Civil Aviation domain, research activities aim to improve airspace capacity and efficiency whilst meeting stringent safety targets. These goals are met by improving performance of existing services whilst also expanding the services provided through the development of new Navigation Aids. One such developmental axe is the provision of safer, more reliable approach and landing operations in all weather conditions. The Global Navigation Satellite System (GNSS) has been identified as a key technology in providing navigation services to civil aviation users [1] [2] thanks to its global coverage and accuracy. The GNSS concept includes the provision of an integrity monitoring function by an augmentation system to the core constellations. This is needed to meet the required performances which cannot be met by the stand-alone constellations. One of the three augmentation systems developed within civil aviation is the GBAS (Ground Based Augmentation System) and is currently standardized by the ICAO to provide precision approach navigation services down to Cat I using the GPS or GLONASS constellations [3]. Studies on-going with the objective to extend the GBAS concept to support Cat II/III precision approach operations with GPS L1 C/A, however some difficulties have arisen regarding ionospheric monitoring. With the deployment of Galileo and Beidou alongside the modernization of GPS and GLONASS, it is envisaged that the GNSS future will be multi-constellation (MC) and multi-frequency (MF). European research activities have focused on the use of GPS and Galileo. The MC/MF GBAS concept should lead to many improvements such as a better modelling of atmospheric effects but several challenges must be resolved before the potential benefits may be realized. Indeed, this PhD has addressed two key topics relating to GBAS, the provision of corrections data within the MC/MF GBAS concept and the impact of tropospheric biases on both the SC/SF and MC/MF GBAS concepts. Due to the tight constraints on GBAS ground to air communications link, the VDB unit, a novel approach is needed. One of the proposals discussed in the PhD project for an updated GBAS VDB message structure is to separate message types for corrections with different transmission rates. Then, this PhD argues that atmospheric modelling with regards to the troposphere has been neglected in light of the ionospheric monitoring difficulties and must be revisited for both nominal and anomalous scenarios. The thesis focuses on how to compute the worst case differential tropospheric delay offline in order to characterize the threat model before extending previous work on bounding this threat in order to protect the airborne GBAS user. In the scope of MC/MF GBAS development, an alternative approach was needed. Therefore, in this PhD project, Numerical Weather Models (NWMs) are used to assess fully the worst case horizontal component of the troposphere. An innovative worst case horizontal tropospheric gradient search methodology is used to determine the induced ranging biases impacting aircraft performing Cat II/III precision approaches with GBAS. This provides as an output a worst case bias as a function of elevation for two European regions.The vertical component is also modelled by statistical analysis by comparing the truth data to the GBAS standardized model for vertical tropospheric correction up to the height of the aircraft. A model of the total uncorrected differential bias is generated which must be incorporated within the nominal GBAS protection levels. In order to bound the impact of the troposphere on the positioning error and by maintaining the goal of low data transmission, different solutions have been developed which remain conservative by assuming that ranging biases conspire in the worst possible way. Through these techniques, it has been shown that a minimum of 3 parameters may be used to characterize a region’s model. Note de contenu : 1- Introduction
2- Navigation performance requirements for civil aviation
3- GNSS processing
4- Optimal processing models/options for MC/MF GBAS
5- Anomalous troposphere modelling for GBAS
6- Anomalous troposphere bounding
7- Conclusions and future workNuméro de notice : 25826 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse française Note de thèse : Thèse de Doctorat : Spécialité : Signal, Image, Acoustique et Optimisation : Toulouse : 2016 Organisme de stage : Laboratoire de Télécommunications (TELECOM-ENAC) nature-HAL : Thèse DOI : sans En ligne : http://www.theses.fr/2016INPT0049 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95116 A fast and accurate algorithm for high-frequency trans-ionospheric path length determination / Dudy D Wijaya in Journal of geodesy, vol 89 n° 12 (december 2015)
[article]
Titre : A fast and accurate algorithm for high-frequency trans-ionospheric path length determination Type de document : Article/Communication Auteurs : Dudy D Wijaya, Auteur Année de publication : 2015 Article en page(s) : pp 1183 - 1196 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] longueur d'onde
[Termes IGN] réfraction atmosphérique
[Termes IGN] troposphèreRésumé : (auteur) This paper presents a fast and accurate algorithm for high-frequency trans-ionospheric path length determination. The algorithm is merely based on the solution of the Eikonal equation that is solved using the conformal theory of refraction. The main advantages of the algorithm are summarized as follows. First, the algorithm can determine the optical path length without iteratively adjusting both elevation and azimuth angles and, hence, the computational time can be reduced. Second, for the same elevation and azimuth angles, the algorithm can simultaneously determine the phase and group of both ordinary and extra-ordinary optical path lengths for different frequencies. Results from numerical simulations show that the computational time required by the proposed algorithm to accurately determine 8 different optical path lengths is almost 17 times faster than that required by a 3D ionospheric ray-tracing algorithm. It is found that the computational time to determine multiple optical path lengths is the same with that for determining a single optical path length. It is also found that the proposed algorithm is capable of determining the optical path lengths with millimeter level of accuracies, if the magnitude of the squared ratio of the plasma frequency to the transmitted frequency is less than 1.33×10−3, and hence the proposed algorithm is applicable for geodetic applications. Numéro de notice : A2015-886 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0841-1 En ligne : https://doi.org/10.1007/s00190-015-0841-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79433
in Journal of geodesy > vol 89 n° 12 (december 2015) . - pp 1183 - 1196[article]GPS satellite surveying / Alfred Leick (2015)
Titre : GPS satellite surveying Type de document : Guide/Manuel Auteurs : Alfred Leick, Auteur ; Lev Rapoport, Auteur ; Dmitry Tatarnikov, Auteur Mention d'édition : 4th edition Editeur : New York, Londres, Hoboken (New Jersey), ... : John Wiley & Sons Année de publication : 2015 Importance : 807 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-1-118-67557-1 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GNSS
[Termes IGN] compensation Lambda
[Termes IGN] Global Positioning System
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement par GNSS
[Termes IGN] troposphèreIndex. décimale : 30.61 Systèmes de Positionnement par Satellites du GNSS Résumé : (Editeur) This book is the classic text on the subject, providing the most comprehensive coverage of global navigation satellite systems applications for surveying. Fully updated and expanded to reflect the field's latest developments, this new edition contains new information on GNSS antennas, Precise Point Positioning, Real-time Relative Positioning, Lattice Reduction, and much more. New contributors offer additional insight that greatly expands the book's reach, providing readers with complete, in-depth coverage of geodetic surveying using satellite technologies. The newest, most cutting-edge tools, technologies, and applications are explored in-depth to help readers stay up to date on best practices and preferred methods, giving them the understanding they need to consistently produce more reliable measurement. Global navigation satellite systems have an array of uses in military, civilian, and commercial applications. In surveying, GNSS receivers are used to position survey markers, buildings, and road construction as accurately as possible with less room for human error. This book provides complete guidance toward the practical aspects of the field, helping readers to: - Get up to speed on the latest GPS/GNSS developments, - Understand how satellite technology is applied to surveying, - Examine in-depth information on adjustments and geodesy, - Learn the fundamentals of positioning, lattice adjustment, antennas, and more. The surveying field has seen quite an evolution of technology in the decade since the last edition's publication. This new edition covers it all, bringing the reader deep inside the latest tools and techniques being used on the job. Surveyors, engineers, geologists, and anyone looking to employ satellite positioning will find GPS Satellite Surveying to be of significant assistance. Note de contenu : 1. INTRODUCTION
2. LEAST-SQUARES ADJUSTMENTS
2.1 Elementary Considerations
2.2 Stochastic and Mathematical Models
2.3 Mixed Model
2.4 Sequential Mixed Model
2.5 Model Specifications
2.6 Minimal and Inner Constraints
2.7 Statistics in Least-Squares Adjustment
2.8 Reliability
2.9 Blunder Detection
2.10 Examples
2.11 Kalman Filtering
3. RECURSIVE LEAST SQUARES
3.1 Static Parameter
3.2 Static Parameters and Arbitrary Time-Varying Variables
3.3 Dynamic Constraints
3.4 Static Parameters and Dynamic Constraints
3.5 Static Parameter, Parameters Subject to Dynamic Constraints, and Arbitrary Time-Varying Parameters
4. GEODESY
4.1 International Terrestrial Reference Frame
4.2 International Celestial Reference System
4.3 Datum
4.4 3D Geodetic Model
4.5 Ellipsoidal Model
4.6 Conformal Mapping Model
4.7 Summary
5. SATELLITE SYSTEMS
5.1 Motion of Satellites
5.2 Global Positioning System
5.3 GLONASS
5.4 Galileo
5.5 QZSS
5.6 Beidou
5.7 IRNSS
5.8 SBAS: WAAS, EGNOS, GAGAN, MSAS, and SDCM
6. GNSS POSITIONING APPROACHES
6.1 Observables
6.2 Operational Details
6.3 Navigation Solution
6.4 Relative Positioning
6.5 Ambiguity Fixing
6.6 Network-Supported Positioning
6.7 Triple-Frequency Solutions
6.8 Summary
7. REAL-TIME KINEMATICS RELATIVE POSITIONING
7.1 Multisystem Considerations
7.2 Undifferenced and Across-Receiver Difference Observations
7.3 Linearization and Hardware Bias Parameterization
7.4 RTK Algorithm for Static and Short Baselines
7.5 RTK Algorithm for Kinematic Rovers and Short Baselines
7.6 RTK Algorithm with Dynamic Model and Short Baselines
7.7 RTK Algorithm with Dynamic Model and Long Baselines
7.8 RTK Algorithms with Changing Number of Signals
7.9 Cycle Slip Detection and Isolation
7.10 Across-Receiver Ambiguity Fixing
7.11 Software Implementation
8. TROPOSPHERE AND IONOSPHERE
8.1 Overview
8.2 Tropospheric Refraction and Delay
8.3 Troposphere Absorption
8.4 Ionospheric Refraction
9. GNSS RECEIVER ANTENNAS
9.1 Elements of Electromagnetic Fields and Electromagnetic Waves
9.2 Antenna Pattern and Gain
9.3 Phase Center
9.4 Diffraction and Multipat
9.5 Transmission Lines
9.6 Signal-to-Noise Ratio
9.7 Antenna TypesNuméro de notice : 22434 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Manuel de cours DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79696 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 22434-01 30.61 Livre Centre de documentation Géodésie Disponible Validity and behaviour of tropospheric gradients estimated by GPS in Corsica / Laurent Morel in Advances in space research, vol 55 n° 1 ([01/01/2015])
[article]
Titre : Validity and behaviour of tropospheric gradients estimated by GPS in Corsica Type de document : Article/Communication Auteurs : Laurent Morel, Auteur ; Eric Pottiaux, Auteur ; Frédéric Durand, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 135 - 149 Langues : Anglais (eng) Descripteur : [Termes IGN] Corse
[Termes IGN] GAMIT
[Termes IGN] GIPSY-OASIS
[Termes IGN] gradient de troposphère
[Termes IGN] retard troposphérique
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) Estimation of tropospheric gradients in GNSS data processing is a well-known technique to improve positioning (e.g. Bar-Sever et al., 1998; Chen and Herring, 1997). More recently, several authors also focused on the estimation of such parameters for meteorological studies and demonstrated their potential benefits (e.g. Champollion et al., 2004). Today, they are routinely estimated by several global and regional GNSS analysis centres but they are still not yet used for operational meteorology.
This paper discusses the physical meaning of tropospheric gradients estimated from GPS observations recorded in 2011 by 13 permanent stations located in Corsica Island (a French Island in the western part of Italy). Corsica Island is a particularly interesting location for such study as it presents a significant environmental contrast between the continent and the sea, as well as a steep topography.
Therefore, we estimated Zenith Total Delay (ZTD) and tropospheric gradients using two software: GAMIT/GLOBK (GAMIT version 10.5) and GIPSY-OASIS II version 6.1. Our results are then compared to radiosonde observations and to the IGS final troposphere products. For all stations we found a good agreement between the ZWD estimated by the two software (the mean of the ZWD differences is 1 mm with a standard deviation of 6 mm) but the tropospheric gradients are in less good agreement (the mean of the gradient differences is 0.1 mm with a standard deviation of 0.7 mm), despite the differences in the processing strategy (double-differences for GAMIT/GLOBK versus zero-difference for GIPSY-OASIS).
We also observe that gradient amplitudes are correlated with the seasonal behaviour of the humidity. Like ZWD estimates, they are larger in summer than in winter. Their directions are stable over the time but not correlated with the IWV anomaly observed by ERA-Interim. Tropospheric gradients observed at many sites always point to inland throughout the year. These preferred directions are almost opposite to the largest slope of the local topography as derived from the world Digital Elevation Model ASTER GDEM v2. These first results give a physical meaning to gradients but the origin of such directions need further investigations.Numéro de notice : A2015-297 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2014.10.004 En ligne : https://doi.org/10.1016/j.asr.2014.10.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76458
in Advances in space research > vol 55 n° 1 [01/01/2015] . - pp 135 - 149[article]Atmospheric water vapour sensing by means of differential absorption spectrometry using solar and lunar radiation / Stefan Walter Münch (2014)
Titre : Atmospheric water vapour sensing by means of differential absorption spectrometry using solar and lunar radiation Type de document : Thèse/HDR Auteurs : Stefan Walter Münch, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2014 Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 92 Importance : 210 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-35-2 Note générale : bibliographie, thèse publiée
Diss., Eidgenössische Technische Hochschule ETH Zürich, Nr. 21491, 2013Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Atmosphère
[Termes IGN] correction troposphérique
[Termes IGN] détecteur à transfert de charge
[Termes IGN] pouvoir de résolution spectrale
[Termes IGN] rayonnement solaire
[Termes IGN] spectromètre
[Termes IGN] spectrométrie
[Termes IGN] teneur en vapeur d'eau
[Termes IGN] troposphèreIndex. décimale : 47.50 Atmosphère Résumé : (auteur) Tropospheric water vapour plays a crucial role in the understanding of a variety of different atmospheric processes, ranging from local weather phenomena to global climate change. Regarding satellite geodesy, water vapour acts as disturbing factor for various measurement methods, causing path delays of radio signals and consequently leads to considerable biases in the measurement results. The spatial and temporal concentration distribution can hardly be modelled and therefore has to be determined instrumentally to correct the influence computationally. The application of the principle of “Differential Optical Absorption Spectroscopy” (DOAS) using the sun as radiation source to locally determine integrated water vapour concentrations (PW), has proven itself as a very potent methodology, with good relative and absolute accuracy, high temporal resolution and comparably low calibration efforts. It also seems especially well suited for validation purposes for independent measurement methods.
The intention of the presented project is to implement the findings from the development of earlier prototype instruments and to contemplate several further aspects related with the DOAS approach to determine atmospheric water vapour: Improved temporal coverage of the measurement method through inclusion of night time measurements with the help of moonlight, which are enabled by means of a massively increased system sensitivity to deal with the up to six orders of magnitude lower intensity of the background radiation with respect to solar measurements. Further it is to investigate, how reliable acquisitions of sun transmission spectra can be achieved, when deploying the system on moving platforms, for possible future validation measurements of satellite-borne radiometer data on satellite ground tracks on the open sea. The prototype instruments developed should particularly feature high field versatility, requiring eased transportability, resistance to weather and not least the possibility of a fully automatic measurement procedure, including instrument self-calibration.
For this purpose two identically constructed compact measurement systems were built. The instruments dispose of a custom-built telescope (heliostat principle) and an optically directly coupled spectrometer unit. The whole system is enclosed in a rugged aluminium hull, including most of the steering electronics. The motorized telescope is able to follow the moving light source fully autonomously, also with the platform moderately moving. A quasi-monochromator with an echelle grating as main dispersion element is used as spectrometer unit, allowing a compact architecture, a great spectral resolution and efficiency at the same time. Together with a back-thinned CCD detector highly resolved images of water vapour absorption lines can be obtained. The primary wavelength range lies between 789 nm and 802 nm, the reciprocal linear dispersion amounts to 7.3 pm/px at a focal length of just 400 mm. A motorized deflection mirror in the spectrometer allows the observation of adjacent spectral windows and serves for the highly precise position stabilization of the spectrum on the CCD sensor.
Test measurements with the sun and the moon as background radiation source show the extraordinarily high system light throughput and the high spectral resolving power of the apparatus. However illumination dependent interference structures on the detector (etaloning) prevent the deduction of usable transmission spectra from the measured raw data. For that reason a variety of optical measures to homogenize the radiation entering the spectrometer with respect to field and aperture are examined. As a feasible solution, with sufficient radiation distribution and a still acceptable intensity attenuation, a short quartz light guiding fibre with a hexagonal cross section has been found and implemented.
For instrumental control a software package has been developed, which autonomously handles the measurement process including the various calibration processes and the interaction of the various sensors and actuators. Additionally a variety of algorithms have been provided, helping to eliminate various defective influences in the raw data, as the correction of stray and false light portions or the elimination of interspersed beat structures in lunar spectra. Furthermore procedures which serve in spectrum processing have been supplied, as for the computation of a holistic intensity baseline or the dynamic determination of apparatus profiles. For the determination of the water vapour concentrations from the measured spectroscopic data established computational procedures could be used mostly.
Various available spectroscopic databases have been analysed regarding the suitability of the listed absorption line parameters for the deduction of reliable water vapour concentrations. Comparison between the two identically built solar spectrometers yield considerable deviations of up to 1.5 kg/m 2 in the zenith integral concentrations which are presumably ascribable to systematic influences likely caused by unrecognized stray light influence. The mean value of the stochastic deviations amounts to about 1.1 % of the slant PW concentration. The cross-comparison with an independent measurement method, in this case GPS meteorology, however also shows significant divergences and thus point to the various further systematic effects which have to be examined more closely, as e.g. the uncertainty of the published spectroscopic parameters regarding line strength and line broadening as well as the baseline determination in the measured spectra.
Despite the considerable sensitivity losses with respect to the originally planned design due to beam homogenization, the methodology has been successfully applied to lunar measurements, albeit with reduced accuracy as stated in stochastic appraisals and with considerably lower temporal resolution.
The project presented here confirms and clarifies the possibilities of the application of DOAS for ground- based remote sensing of integral water vapour concentrations, but also gives clear indication on the different systematic biases which have to be examined more closely, e.g. regarding the accuracy of the spectroscopic parameters (both, for line strength and line broadening), as well as the determination procedure of the baseline in the measured spectra. This work also points out the chances as well as the serious difficulties which arise from the design, construction and deployment of highly integrated DOAS spectrometers of high performance. Regarding the application of various optical components and detectors for the development of similar instruments valuable insights have been gathered.Numéro de notice : 14913 Affiliation des auteurs : non IGN Autre URL associée : URL ETH Zurich Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : PhD : Sciences : ETH Zurich : 2013 DOI : 10.3929/ethz-a-010006561 En ligne : http://e-collection.library.ethz.ch/view/eth:7591 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76813 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 14913-01 47.50 Livre Centre de documentation En réserve M-103 Disponible DORIS tropospheric estimation at IGN : Current strategies, GPS intercomparisons and perspectives / Pascal Willis (2014)PermalinkTroposphere delays from space geodetic techniques, water vapor radiometers, and numerical weather models over a series of continuous VLBI campaigns / Kamil Teke in Journal of geodesy, vol 87 n° 10-12 (October - December 2013)PermalinkComparison of IASI water vapour products over complex terrain with COPS campaign data / Guido Masiello in Meteorologische Zeitschrift, vol 22 n° 4 (August 2013)PermalinkLes leçons de l'expérience AMMA en matière de prévision numérique du temps / Fatima Karbou in La Météorologie, n° spéc (octobre 2012)PermalinkEstimating horizontal tropospheric gradients in DORIS data processing: preliminary results / Pascal Willis (2012)Permalink4D GPS water vapor tomography: new parameterized approaches / Donat Perler in Journal of geodesy, vol 85 n° 8 (August 2011)Permalinkvol 85 n° 7 - July 2011 - CONT08 -continuous geodetic VLBI campaign 2008 August 12-26 2008 (Bulletin de Journal of geodesy) / Axel NothnagelPermalinkMulti-technique comparison of troposphere zenith delays and gradients during CONT08 / Kamil Teke in Journal of geodesy, vol 85 n° 7 (July 2011)PermalinkPermalinkLa campagne Cops : genèse et cycle de vie de la convection en région montagneuse / Evelyne Richard in La Météorologie, n° 64 ([01/01/2009])Permalink