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A first look at the effects of ionospheric signal bending on a globally processed GPS network / E. Petrie in Journal of geodesy, vol 84 n° 8 (August 2010)
[article]
Titre : A first look at the effects of ionospheric signal bending on a globally processed GPS network Type de document : Article/Communication Auteurs : E. Petrie, Auteur ; M. King, Auteur ; P. Moore, Auteur ; David Lavallée, Auteur Année de publication : 2010 Article en page(s) : pp 491 - 499 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] atténuation du signal
[Termes IGN] correction ionosphérique
[Termes IGN] propagation ionosphérique
[Termes IGN] réfraction atmosphérique
[Termes IGN] retard troposphérique zénithal
[Termes IGN] signal GPSRésumé : (Auteur) This study provides a first attempt at quantifying potential signal bending effects on the GPS reference frame, coordinates and zenith tropospheric delays (ZTDs). To do this, we homogeneously reanalysed data from a global network of GPS sites spanning 14 years (1995.0–2009.0). Satellite, Earth orientation, tropospheric and ground station coordinate parameters were all estimated. We tested the effect of geometric bending and dTEC bending corrections, which were modelled at the observation level based, in part, on parameters from the International Reference Ionosphere 2007 model. Combined, the two bending corrections appear to have a minimal effect on site coordinates and ZTDs except for low latitude sites. Considering five days (DOY 301–305, 28 October–1 November 2001) near ionospheric maximum in detail, they affect mean ZTDs by up to ~1.7 mm at low latitudes, reducing to negligible levels at high latitudes. Examining the effect on coordinates in terms of power-spectra revealed the difference to be almost entirely white noise, with noise amplitude ranging from 0.3 mm (high latitudes) to 2.4 mm (low latitudes). The limited effect on station coordinates is probably due to the similarity in the elevation dependence of the bending term with that of tropospheric mapping functions. The smoothed z-translation from the GPS reference frame to ITRF2005 changes by less than 2 mm, though the effect combines positively with that from the second order ionospheric refractive index term. We conclude that, at the present time, and for most practical purposes, the geometric and dTEC bending corrections are probably negligible at current GPS/reference frame precisions. Numéro de notice : A2010-440 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-010-0386-2 Date de publication en ligne : 01/06/2010 En ligne : https://doi.org/10.1007/s00190-010-0386-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30633
in Journal of geodesy > vol 84 n° 8 (August 2010) . - pp 491 - 499[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2010081 SL Revue Centre de documentation Revues en salle Disponible Wide-area RTK: high precision positioning on a continental scale / Manuel Hernández-Pajares in Inside GNSS, vol 5 n° 2 (March - April 2010)
[article]
Titre : Wide-area RTK: high precision positioning on a continental scale Type de document : Article/Communication Auteurs : Manuel Hernández-Pajares, Auteur ; et al., Auteur Année de publication : 2010 Article en page(s) : 12 p. ; pp 35 - 46 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] atmosphère terrestre
[Termes IGN] correction du signal
[Termes IGN] modèle ionosphérique
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] propagation ionosphérique
[Termes IGN] récepteur GNSS
[Termes IGN] traitement de données GNSSRésumé : (Auteur) Real-time corrections at the decimeter level over an entire continent? The challenge lies in minimizing the ranging errors from signals propagating through the Earth’s atmosphere. European researchers describe how it can be done using a Wide Area Real-Time Kinematic concept that exploits the full geometry of the observations, a central processing facility, and undifferenced processing of measurements from widely space GNSS reference receivers to create a real-time ionospheric model of the signal slant delays. Copyright Gibbons Media & Research LLC Numéro de notice : A2010-619 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33569
in Inside GNSS > vol 5 n° 2 (March - April 2010) . - 12 p. ; pp 35 - 46[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 159-2010021 SL Revue Centre de documentation Revues en salle Disponible Documents numériques
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Wide-area RTK ... - pdf éditeurAdobe Acrobat PDF Improving the GNSS positioning stochastic model in the presence of ionospheric scintillation / M. Aquino in Journal of geodesy, vol 83 n° 10 (October 2009)
[article]
Titre : Improving the GNSS positioning stochastic model in the presence of ionospheric scintillation Type de document : Article/Communication Auteurs : M. Aquino, Auteur ; João F.G. Monico, Auteur ; A.H. Dodson, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 953 - 966 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] modèle stochastique
[Termes IGN] positionnement par GNSS
[Termes IGN] propagation ionosphérique
[Termes IGN] récepteur GNSS
[Termes IGN] scintillation
[Termes IGN] teneur totale en électronsRésumé : (Auteur) Ionospheric scintillations are caused by time- varying electron density irregularities in the ionosphere, occurring more often at equatorial and high latitudes. This paper focuses exclusively on experiments undertaken in Europe, at geographic latitudes between ~50°N and ~80°N, where a network of GPS receivers capable of monitoring Total Electron Content and ionospheric scintillation parameters was deployed. The widely used ionospheric scintillation indices S4 and {\sigma_{\varphi}} represent a practical measure of the intensity of amplitude and phase scintillation affecting GNSS receivers. However, they do not provide sufficient information regarding the actual tracking errors that degrade GNSS receiver performance. Suitable receiver tracking models, sensitive to ionospheric scintillation, allow the computation of the variance of the output error of the receiver PLL (Phase Locked Loop) and DLL (Delay Locked Loop), which expresses the quality of the range measurements used by the receiver to calculate user position. The ability of such models of incorporating phase and amplitude scintillation effects into the variance of these tracking errors underpins our proposed method of applying relative weights to measurements from different satellites. That gives the least squares stochastic model used for position computation a more realistic representation, vis-a-vis the otherwise ‘equal weights’ model. For pseudorange processing, relative weights were com- puted, so that a ‘scintillation-mitigated’ solution could be performed and compared to the (non-mitigated) ‘equal weights’ solution. An improvement between 17 and 38% in height accuracy was achieved when an epoch by epoch differential solution was computed over baselines ranging from 1 to 750 km. The method was then compared with alternative approaches that can be used to improve the least squares stochastic model such as weighting according to satellite elevation angle and by the inverse of the square of the standard deviation of the code/carrier divergence (sigma CCDiv). The influence of multipath effects on the proposed mitigation approach is also discussed. With the use of high rate scintillation data in addition to the scintillation indices a carrier phase based mitigated solution was also implemented and compared with the conventional solution. During a period of occurrence of high phase scintillation it was observed that problems related to ambiguity resolution can be reduced by the use of the proposed mitigated solution. Copyright Springer Numéro de notice : A2009-430 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-009-0313-6 En ligne : https://doi.org/10.1007/s00190-009-0313-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30061
in Journal of geodesy > vol 83 n° 10 (October 2009) . - pp 953 - 966[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09091 SL Revue Centre de documentation Revues en salle Disponible Ionospheric modeling for precise GNSS applications / Y. Memarzadeh (2009)
Titre : Ionospheric modeling for precise GNSS applications Type de document : Monographie Auteurs : Y. Memarzadeh, Auteur Editeur : Delft : Netherlands Geodetic Commission NGC Année de publication : 2009 Collection : Netherlands Geodetic Commission Publications on Geodesy, ISSN 0165-1706 num. 71 Importance : 208 p. Format : 17 x 24 cm ISBN/ISSN/EAN : 978-90-6132-314-3 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GNSS
[Termes IGN] correction ionosphérique
[Termes IGN] double différence
[Termes IGN] modèle ionosphérique
[Termes IGN] positionnement différentiel
[Termes IGN] positionnement par GNSS
[Termes IGN] précision centimétrique
[Termes IGN] propagation du signal
[Termes IGN] propagation ionosphérique
[Termes IGN] simple différence
[Termes IGN] temps réel
[Termes IGN] teneur totale en électrons
[Termes IGN] traitement de données GNSSIndex. décimale : 30.61 Systèmes de Positionnement par Satellites du GNSS Résumé : (Auteur) The main objective of this thesis is to develop a procedure for modeling and predicting ionospheric Total Electron Content (TEC) for high precision differential GNSS applications. As the ionosphere is a highly dynamic medium, we believe that to have a reliable procedure it is necessary to transfer the high temporal resolution GNSS network data into the spatial domain. This objective led to the development of a recursive physics-based model for the regular TEC variations and an algorithm for real-time modeling of the medium-scale Traveling Ionospheric Disturbances (MS-TID). The research described in this thesis can roughly be divided into three parts.
The main application of these developments can be found in Network RTK. Network-RTK is a technique based on a network of reference receivers to provide cm-level positioning accuracy in real time for users in the field. To get centimeter accuracy after a short (minutes) initialization period the ionospheric delay for the user's receiver needs to be predicted very precisely between the ionospheric pierce points of the reference receivers at the double difference level. Having the cm-level accuracy in the ionospheric interpolation is crucial for the carrier phase ambiguity resolution by the user. To achieve high precision in the ionospheric interpolation, regular and irregular variability of TEC in time and space should be taken into account. The regular TEC variation, which can reach several hundreds TEC units, is mainly a function of solar zenith angle. The irregular (or non-repeatable) variations are mainly wavelike effects associated with Traveling Ionospheric Disturbances (TID).
Although TID effects on the TEC are of the order of 0.1 TEC unit, MS-TIDs, with a typical wavelength less than a few hundred kilometers, is one of the main obstacles for accurate spatial interpolation of ionospheric induced delays in a medium-scale reference GPS network. Since most of interpolation methods either use spatial linear (or quadratic) interpolation or fit a lower-order surface, the methods are not capable to model the phase-offset, caused by MS-TIDs, at distinct ionospheric pierce points. There are two major complications. Firstly, interpolation must be done at the double-difference level, which involves taking single differences between ionospheric delays for the same satellite between two different receivers, followed by differencing single differences for different satellites. This means that two different patches of the ionosphere are involved, each related to a different satellite, and each possibly associated with different TIDs. Secondly, for operational network RTK, a real-time strategy for TID detection and modeling is needed.
In the first part the performance of several empirical ionosphere models for the regular TEC variation, such as Klobuchar, NeQuick, and the IGS Global Ionosphere Maps (GIM) are studied in the mid-latitude region using GPS data. Our results show that the GIM was able to correct the absolute slant ionospheric delay to better than 80% under different geomagnetic conditions of the ionosphere. The NeQuick model, which performed better than the Klobuchar model, could correct about 60% of the slant ionospheric delay. NeQuick is a real-time ionospheric correction model for the future European Galileo navigation system. A key input parameter for NeQuick is the effective ionization parameter (Az), which will be provided as a second order polynomial in the Galileo broadcast message to single-frequency users. The coefficients of the polynomial will be estimated daily from at least 20 permanent Galileo monitoring stations. As Galileo is under development, we propose an alternative approach for estimating Az using Global Ionospheric Maps (GIM). The main advantages of the alternative approach over the standard approach are: (1) the alternative approach is more reliable, because, each IGS GIM is based on data of up to 300 GNSS stations world-wide and each IGS GIM is the combination of results of up to four analysis centers, (2) the coefficients are more representative for all regions on the world because they are computed from a world-wide grid instead of about 20 distinct locations, (3) with the alternative procedure it is possible to provide Az in a different representation, for instance using a higher order polynomial, grid, or other function types, and (4) the computational effort is much smaller assuming the IGS GIMs have already been computed.
In the second part a normal ionosphere is defined using Chapman's ion production theory to approximate the regular variability of the Earth's ionosphere. The normal ionosphere consists of lower and upper region. The lower region is formed in a photochemical equilibrium resulting in a Chapman layer. The upper region is formed in a diffusive equilibrium, whilst ignoring the geomagnetic field, resulting in a new Chapman like ionospheric layer. Integration of the continuity equation of the normal ionosphere over height leads to a Boundary Value Problem (BVP) for the temporal evolution of VTEC. Solution of the BVP results in a novel recursive model for the regular TEC variation as a function of solar zenith angle. The main motivation for developing this model is that the empirical models of the first part were either ill-suited or too complicated to model and predict the regular variation of TEC for high precision differential GNSS applications. The performance of the new model is tested at local and global scales using GIM. In general, despite the geomagnetic field was ignored, the cases analyzed show that the model gives a good overall representation of the regular variation of VTEC in the mid-latitude region under a geomagnetically quiet ionosphere. This is an important result that shows the potential of the model for a number of applications. Since the model has a recursive form it is ideally suited to use as time update equation in a dynamic data processing or Kalman filter. Another application is to use it for removing the geometry-dependent trend from time series of GPS-provided ionospheric delays to provide a pure TID observation, which is carried out in the third part of this thesis.
In the third part, a new algorithm for the real-time detection and modeling of MS-TID effects is developed. In order to eliminate effects from large-scale TIDs, the algorithm uses between-receiver single-difference (SD) ionospheric delays in a medium scale GPS network. Although single-differencing also eliminates to some extend the geometry-dependent trend, the remaining part cannot be neglected. In this thesis, we fit the SD data to the recursive model which was developed in the second part of the thesis. Any wavelike fluctuations in the data with respect to the model are assumed to be from MS-TID effects. The detrended SD data are the main input of the algorithm. The algorithm consists of six steps: initialization, detection, scraping, cross-correlation, parameter estimation, and ending. A MS-TID is assumed to be a planar longitudinal traveling wave with spatially independent amplitude that propagates in an ionospheric patch. All characteristic parameters of the MS-TID wave (e.g. period, phase velocity, propagation direction, and amplitude) are considered to be time dependent, while the Doppler-shift caused by the satellite motion is taken into account in the estimation step. The performance of the algorithm is tested with GPS data from a network. Although real TIDs are not perfect waves, the algorithm was able to model (in time and in space) the MS-TID to a large extend. The performance was found to be comparable with the Kriging interpolation method. This is an important first result, in part because these two methods are based on different principles, but also because there is still room for improvement in our algorithm. With our physics based model it is possible to avoid the planar wave approximation and take the phase-offset of the wave into account, something which is not possible with Kriging.Note de contenu : Curriculum Vitae Acknowledgments Notation and Symbols Acronyms
1 Introduction
1.1 Background
1.2 Research objectives
1.3 Outline of the thesis
1.4 Contributions of this research
2 The Earth's Atmosphere, Sun, and Geomagnetism
2.1 The Earth's Atmosphere .
2.1.1 Pressure, temperature and density variations
2.1.2 Diffusive equilibrium
2.1.3 Upper atmosphere .
2.2 The Sun
2.2.1 The Solar radiation
2.2.2 Variation of the radiation intensity
2.2.3 Solar radiations index (F10.7) .
2.3 Geomagnetism .
2.3.1 The earth's magnetic dipole field
2.3.2 The real geomagnetic field
2.3.3 Geomagnetic storm
2.3.4 Geomagnetic indices
3 Physics of the Earth's Ionosphere
3.1 Interaction of solar radiation with the Earth's upper atmosphere
3.2 Ionosphere formation theory
3.2.1 Plasma continuity equation
3.2.2 Ion production
3.2.3 Ion and electron disappearance .
3.2.4 Chapman layer
3.3 Transport process in the ionosphere .
3.3.1 Charged particle motion in a magnetic field .
3.3.2 Plasma diffusion .
3.3.3 Thermospheric wind .
3.3.4 Electromagnetic drift
3.4 Ionospheric stratification .
3.4.1 The D-Region
3.4.2 The E-Region
3.4.3 The F-Region
3.4.4 The topside region and the protonosphere .
3.4.5 Vertical electron density profile of the ionosphere
3.4.6 Characteristic parameters of the ionospheric regions
3.5 Spatial and temporal variability of the ionosphere
3.5.1 Regular variations
3.5.2 Geomagnetic regions .
3.6 Solar disturbances
3.6.1 Ionospheric disturbances .
3.6.2 Atmospheric gravity waves
3.6.3 Traveling ionospheric disturbances
4 Ionospheric delay measured from GNSS
4.1 Global Navigation Satellite Systems (GNSS) .
4.2 GNSS observation equations
4.2.1 Code or pseudo-range observation equation
4.2.2 Carrier beat phase observation equation
4.2.3 Simplifications of the observation equations
4.2.4 Tropospheric effects
4.3 Ionospheric propagation of GNSS signals .
4.3.1 Inhomogeneity of the ionosphere .
4.3.2 Dispersivity of the ionosphere .
4.3.3 Anisotropy of the ionosphere .
4.3.4 Ionospheric refractive index
4.3.5 Ionospheric first-, higher-order and bending effects . .
4.4 Ionospheric Total Electron Content (TEC)
4.4.1 A single-layer ionosphere approximation
4.4.2 Approximation of the higher-order and bending effects
4.5 Ionospheric models
4.5.1 Klobuchar model
4.5.2 Global Ionosphere Maps
4.6 Slant ionospheric delay measurements from GNSS
4.6.1 Network processing
4.6.2 Geometry-free linear combination 4.7 Summary
5 NeQuick 3D Ionospheric Electron Density Profiler
5.1 Ionospheric electron density model NeQuick
5.1.1 NeQuick model formulation for the bottom side (h < hmaXtF2)
5.1.2 NeQuick model formulation for the top side (hmax,F2 < /')
5.2 Characteristic parameters of the anchor points
5.2.1 Peak height of the F'2 region
5.2.2 Thickness parameters of the semi-Epstein layers
5.3 Providing the ionosonde parameters for NeQuick .
5.3.1 CCIR maps of /0F2 and M(3000)F2
5.3.2 Diagrammatic presentation of NeQuick
5.4 NeQuick for the Galileo navigation system
5.4.1 Effective Ionization Level (Az parameter) .
5.4.2 Estimation of the effective ionization level (nominal approach)
5.4.3 Improved version of NeQuick .
5.5 Estimation of the effective ionization level using GIM .
5.5.1 Estimation of the effective ionization level (alternative approach
5.5.2 Daily grid-based map of the effective ionization level
5.5.3 Az parameter for single point positioning .
5.6 Validation of the alternative approach .
5.6.1 Consistency of the approaches .
5.6.2 Modeling the spatial dependency of the Az parameter
5.6.3 Correlation between Az and F10.7
5.7 Performance of the NeQuick ionospheric model
5.7.1 Data specifications and processing
5.7.2 Comparison between the model errors .
5.8 Concluding remarks ..
6 Physics-Based Modeling of TEC
6.1 Normal ionosphere
6.1.1 Vertical electron density profile in the normal ionosphere . . . .
6.1.2 VTEC in the normal E-region .
6.1.3 VTEC in the normal F-region .
6.1.4 Combined VTEC of the normal ionosphere
6.1.5 Slant TEC in the normal ionosphere
6.2 Recursive model of VTEC in the normal ionosphere
6.2.1 Parametrization of the VTEC model .
6.2.2 Providing the model parameters
6.2.3 Functional model for estimating the parameters
6.2.4 Linearization of the functional model .
6.2.5 Least-squares solution of the model parameters
6.3 Performance of the VTEC model .
6.3.1 Local test of the VTEC model .
6.3.2 Global test of the VTEC model .
6.3.3 Applications of the VTEC model 6.4 Summary
7 Real-Time Modeling for Medium-Scale TID
7.1 Introduction
7.2 Medium-Scale Traveling Ionospheric Disturbances
7.3 Mechanical longitudinal wave equation
7.3.1 Traveling plane wave
7.3.2 Standing plane wave
7.4 GPS-provided TID observation .
7.4.1 Geometry-dependent trend of slant ionospheric delay
7.4.2 TID observation
7.4.3 Single-difference TID observation .
7.4.4 Double-difference TID observation .
7.5 TID observation equation .
7.5.1 Doppler-shift on TID observation .
7.6 Estimation of TID wave parameters
7.6.1 Period determination
7.6.2 TID wave vector determination
7.6.3 TID wave amplitude determination
7.7 Real-Time Medium-scale TID modeling
7.7.1 Initialization step
7.7.2 TID detection and scraping steps .
7.7.3 Cross correlation step .
7.7.4 TID parameter estimation .
7.7.5 TID ending .
7.7.6 Flowchart of the Real-Time TID modeling algorithm
7.7.7 Dependency on reference baseline .
7.7.8 Sensitivity to temporal resolution .
7.8 Implementation of the Real-Time TID modeling .
7.8.1 Case study: PRN 02
7.8.2 Case study: PRN 08
7.9 Conclusions and remarks
8 Conclusions and recommendations
8.1 Estimation of effective ionization for NeQuick .
8.2 Spatial and temporal variation of effective ionization level .
8.3 Performance of global TEC models
8.4 Model of temporal evolution of VTEC .
8.5 Modeling Medium-Scale Traveling Ionospheric Disturbances
Bibliography
IndexNuméro de notice : 15510 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62743 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15510-01 30.61 Livre Centre de documentation Géodésie Disponible Precise point positioning with GPS: A new approach for positioning, atmospheric studies, and signal analysis / Rodrigo Figueiredo Leandro (2009)
Titre : Precise point positioning with GPS: A new approach for positioning, atmospheric studies, and signal analysis Type de document : Thèse/HDR Auteurs : Rodrigo Figueiredo Leandro, Auteur Editeur : Fredericton [Canada] : University of New Brunswick Année de publication : 2009 Collection : Technical report num. 267 Importance : 232 p. Format : 21 x 30 cm Note générale : bibliographie
Ph.D. dissertation, Department of Geodesy and Geomatics Engineering, University of New Brunswick, Fredericton, New Brunswick, CanadaLangues : Anglais (eng) Descripteur : [Termes IGN] bruit (théorie du signal)
[Termes IGN] erreur systématique
[Termes IGN] estimation statistique
[Termes IGN] horloge atomique
[Termes IGN] modèle atmosphérique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] récepteur monofréquence
[Termes IGN] retard ionosphèrique
[Termes IGN] trajet multipleRésumé : (auteur) Precise Point Positioning (PPP) is one of the existing techniques to determine point coordinates using a GPS (Global Positioning System) receiver. In this technique observations collected by a single receiver are used in order to determine the three components of the coordinates, as well as other parameters, such as the receiver clock error and total neutral atmosphere delay. The PPP technique is the subject of this thesis. The idea is that PPP could be used not only for positioning, but for a number of different tasks, as GPS data analysis. The observation model used in this technique has to take into consideration a number of effects present on GPS signals, and observations are un-differenced (there are no differences between receivers or between satellites). This makes PPP a powerful data analysis tool which is sensible to a variety of parameters. When the observation model is designed for positioning, most of these parameters (e.g., satellite clocks) are used as known quantities, but in this research the observation model was modified and enhanced to develop a PPP package that can be used as a tool for determining other parameters rather than position, receiver clock error and neutral atmosphere delay. These estimated parameters include ionospheric delay, code biases, satellite clock errors, and code multipath plus noise. Existing neutral atmosphere delay models have also been studied in this thesis, and an enhanced model has been developed and has had its performance assessed. The development of the model is based on measured meteorological parameters, and the rationale of the model is established in order to make its use as practical as possible for users of positioning techniques, such as PPP. Note de contenu : 1. Introduction
1.1. Motivation
1.2. Objectives and contributions
1.3. Outline of the thesis
2. Precise Point Positioning and GPS Analysis and Positioning Software (GAPS)
2.1. A bit of history, and GAPS’s role in PPP research and development
2.2. The positioning observation model
2.3. Observations adjustment
2.4. Corrections
3. Ionospheric delay estimation filter
3.1. Introduction
3.2. Ionospheric delay estimation filter
3.3. Results analysis
3.4. Chapter remarks
4. Estimation of code biases by means of PPP
4.1. Introduction
4.2. PPP-based P1-C1 code bias estimation
4.3. PPP-based P2-C2 code bias estimation
4.5. Chapter remarks
5. Code multipath and noise estimation with PPP
5.1. Iono-free code multipath plus noise estimates
5.2. L1 and L2 code multipath plus noise estimates
5.3. Comparison with TEQC
5.4. Analysis of L2C code quality
5.5. Chapter remarks
6. Single-receiver satellite pseudo-clock estimation
6.1. Derivation of the satellite pseudo-clocks
6.2. An example of generation and use of satellite pseudo-clocks
6.3. Chapter remarks
7. Neutral Atmosphere prediction models for GNSS positioning
7.1. Introduction
7.2. UNB wide area models
7.3. UNB wide area model for North America – UNBw.na
7.4. UNBw.na validation with ray-traced delays
7.5. Chapter remarks
8. Conclusions and recommendationsNuméro de notice : 14901 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : PhD : Geodesy and Geomatics Engineering : University of New Brunswick : Canada : 2009 DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76787 Weather Report : Meteorological applications of GNSS from space and on the ground / P. Poli in Inside GNSS, vol 3 n° 8 (November - December 2008)PermalinkPrediction, detection and correction of Faraday: rotation in full-polarimetric L-Band SAR data / F.J. Meyer in IEEE Transactions on geoscience and remote sensing, vol 46 n° 10 Tome 2 (October 2008)PermalinkA systematic investigation of optimal carrier-phase combinations for modernized triple-frequency GPS / Marc Cocard in Journal of geodesy, vol 82 n° 9 (September 2008)PermalinkImproving long-range RTK: getting a better handle on the biases / D. Kim in GPS world, vol 19 n° 3 (March 2008)PermalinkContribution of ionospheric irregularities to the error of dual-frequency GNSS positioning / B.C. Kim in Journal of geodesy, vol 81 n° 3 (March 2007)PermalinkCalibration errors on experimental slant total electron content (TEC) determined with GPS / L. Ciraolo in Journal of geodesy, vol 81 n° 2 (February 2007)PermalinkIonospheric modeling: the key to GNSS ambiguity resolution / T. Richert in GPS world, vol 16 n° 6 (June 2005)PermalinkL'utilisation du GPS pour l'imagerie de l'ionosphère / J. Artru in Géochronique, n° 94 (juin - août 2005)PermalinkPermalinkCelebrating a decade of the International GPS Service, Workshop & Symposium 2004 / Michael Meindl (2004)Permalink