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Titre : Advanced modeling and algorithms for high-precision GNSS analysis Type de document : Thèse/HDR Auteurs : Kan Wang, Auteur Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Année de publication : 2016 Collection : Dissertationen ETH num. 23188 Note générale : bibliographie
thesis submitted to attain the degree of doctor of sciences of ETH ZurichLangues : Anglais (eng) Descripteur : [Termes IGN] ambiguïté entière
[Termes IGN] antenne GPS
[Termes IGN] centre de phase
[Termes IGN] données BeiDou
[Termes IGN] données Galileo
[Termes IGN] données GPS
[Termes IGN] double différence
[Termes IGN] erreur systématique
[Termes IGN] GPS en mode différentiel
[Termes IGN] horloge
[Termes IGN] phase GNSS
[Termes IGN] positionnement cinématique
[Termes IGN] récepteur GNSS
[Termes IGN] récepteur trifréquence
[Termes IGN] résolution d'ambiguïté
[Termes IGN] retard ionosphèrique
[Termes IGN] Suisse
[Termes IGN] trajet multiple
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) In the recent ten years, the Global Navigation Satellite System (GNSS) processing has experienced a fast development in many areas including the increasing number of frequencies, the higher quality of positioning instruments, e.g. the receiver clocks and the satellite clocks, and more integrated modeling and calculation strategies. This thesis includes investigations of different modeling and parameterization methods in modern GNSS positioning with the focus on three important positioning error sources: the receiver clock errors, the phase ambiguities and the ionospheric delays.
The thesis shows that making use of the high-quality receiver clocks and applying appropriate receiver clock modeling can help to improve the kinematic height estimates, which are highly correlated with the receiver clock parameters. An efficient pre-elimination and back-substitution strategy of epoch parameters with relative clock constraints between subsequent and near-subsequent epochs has been developed to enable processing of, e.g., high-rate data. A detailed analysis of the relationship between the clock quality and the improvement of kinematic heights has been performed. Studies were also conducted to decorrelate the receiver clock parameters, the kinematic heights and the troposphere parameters. Experiments with real data have shown that appropriate deterministic and stochastic clock models can also be helpful to increase the resolution of the estimated Zenith Path Delay (ZPD) parameters without obvious degradation of the stability of the kinematic heights.
The second aspect of the thesis focuses on the resolution of triple-frequency phase ambiguities with different linear combinations. A complete analytical investigation of Geometry-Free (GF) and Ionosphere-Free (IF) triple-frequency phase ambiguity resolution with minimized noise level has been performed for different frequency triplets. The analysis was done separately for the best two linear combinations and the third one. Experiments have shown that the fractional parts and the formal errors of the combined ambiguities of the best two linear combinations are relatively small for Galileo E1, E5b and E5a and GPS L1, L2 and L5 triplets, while the third linear combination remains a challenge. Further analysis with the geostationary satellites of the Beidou Navigation Satellite System (BDS) elaborated in the framework of this thesis has also confirmed that the combined ambiguities from the best two GF and IF linear combinations can be fixed by rounding, while the estimated ambiguities on L1 have relatively large deviations from the values obtained from the traditional dual-frequency double-difference ambiguity resolution. Apart from the triple-frequency ambiguity resolution on the double-difference level, the so-called track-to-track ambiguities between different tracks of the same receiver and the same satellite have also been investigated for the best two triple-frequency linear combinations using GPS L1, L2 and L5 as well as Galileo E1, E5b and E5a observations. The outcome demonstrates that elevation-dependent influences on the observations like Phase Center Variations (PCVs), Phase Center Offsets (PCOs) and multipath are important for the fixing of the track-to-track ambiguities.
The combined track-to-track ambiguities using the best two linear combinations are also effective in detecting problems in the observation data.
The third aspect of the thesis includes the investigation of the differential ionospheric delays and gradients in the region of Switzerland from 1999 to 2013. In differential Global Positioning System (GPS) positioning, the ionospheric delays for short baselines are in most cases small enough to be ignored, except under extreme conditions, e.g., during ionospheric stormy days, and for applications with high integrity requirements, e.g., during approach and landing of aircrafts. This thesis introduces an algorithm using double-difference phase measurements with resolved phase ambiguities and global ionosphere maps provided by the Center for Orbit Determination in Europe (CODE) to extract the single-difference ionospheric delays, and enabling an automatic and robust processing of the data over 15 years. The results show that the daily maximum slant ionospheric gradients calculated from the differential slant ionopheric delays and the baseline lengths from 1999 to 2013 are below the slant ionosphere gradient boundary of the Conterminous United States (CONUS) ionospheric anomaly threat model.Numéro de notice : 17250 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : dissertation : sciences : ETH Zurich : 2016 En ligne : http://dx.doi.org/10.3929/ethz-a-010610972 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81986 Code shift keying : prospects for improving GNSS signal design / Axel Garcia-Pena in Inside GNSS, vol 10 n° 6 (November - December 2015)
[article]
Titre : Code shift keying : prospects for improving GNSS signal design Type de document : Article/Communication Auteurs : Axel Garcia-Pena, Auteur ; Marion Aubault-Roudier, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 52 - 62 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] modulation du signal
[Termes IGN] phase GNSSRésumé : (éditeur) This article presents the code shift keying (CSK) modulation principle and highlights some of its specific features related to demodulation performance. CSK behaves like a M-ary signaling technology and presents interesting capabilities and features to solve some of the GNSS industry’s current dilemmas. CSK provides distinctive demodulation properties but does not outperform BPSK implementation with equivalent bit rate and message time duration for the cases presented here. However, achieving additional improvement of the CSK modulation is still expected; for instance, optimizing error correction codes for CSK may reverse this trend. Numéro de notice : A2015--015 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80796
in Inside GNSS > vol 10 n° 6 (November - December 2015) . - pp 52 - 62[article]Documents numériques
en open access
Code shift keyingAdobe Acrobat PDF Double phase estimator : Towards a new perception of the subcarrier component / Daniele Borio in Inside GNSS, vol 10 n° 3 (May - June 2015)
[article]
Titre : Double phase estimator : Towards a new perception of the subcarrier component Type de document : Article/Communication Auteurs : Daniele Borio, Auteur Année de publication : 2015 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] phase GNSS
[Termes IGN] signal GNSSRésumé : (éditeur) The subcarrier introduced in binary offset carrier (BOC) modulated signals has been perceived as a part of the signal code, as a source of ambiguity, and as a nuisance component that should be removed. This article introduces an advanced tracking algorithm that exploits a new conception of the subcarrier to fully benefit from the structure of BOC-modulated signals. Numéro de notice : A2015-251 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.insidegnss.com/node/4501 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76297
in Inside GNSS > vol 10 n° 3 (May - June 2015)[article]An enhanced strategy for GNSS data processing of massive networks / H. Chen in Journal of geodesy, vol 88 n° 9 (September 2014)
[article]
Titre : An enhanced strategy for GNSS data processing of massive networks Type de document : Article/Communication Auteurs : H. Chen, Auteur ; W. Jiang, Auteur ; Maorong Ge, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 857-867 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] longueur d'onde
[Termes IGN] phase GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïtéRésumé : (Auteur)Although the computational burden of global navigation satellite systems (GNSS) data processing is nowadays already a big challenge, especially for huge networks, integrated processing of denser networks with data of multi-GNSS and multi-frequency is desired in the expectation of more accurate and reliable products. Based on the concept of carrier range, in this study, the precise point positioning with integer ambiguity resolution is engaged to obtain the integer ambiguities for converting carrier phases to carrier ranges. With such carrier ranges and pseudo-ranges, rigorous integrated processing is realized computational efficiently for the orbit and clock estimation using massive networks. The strategy is validated in terms of computational efficiency and product quality using data of the IGS network with about 460 stations. The experimental validation shows that the computation time of the new strategy increases gradually with the number of stations. It takes about 14 min for precise orbit and clock determination with 460 stations, while the current strategy needs about 82 min. The overlapping orbit RMS is reduced from 27.6 mm with 100 stations to 24.8 mm using the proposed strategy, and the RMS could be further reduced to 23.2 mm by including all 460 stations. Therefore, the new strategy could be applied to massive networks of multi-GNSS and multi-frequency receivers and possibly to achieve GNSS data products of higher quality. Numéro de notice : A2013-546 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0727-7 Date de publication en ligne : 05/06/2014 En ligne : https://doi.org/10.1007/s00190-014-0727-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74028
in Journal of geodesy > vol 88 n° 9 (September 2014) . - pp 857-867[article]Réservation
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Titre : Improved convergence for GNSS precise point positioning Type de document : Thèse/HDR Auteurs : Simon Banville, Auteur Editeur : Fredericton [Canada] : University of New Brunswick Année de publication : 2014 Collection : Technical report num. 294 Importance : 293 p. Format : 21 x 30 cm Note générale : bibliographie
dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Geodesy and Geomatics EngineeringLangues : Anglais (eng) Descripteur : [Termes IGN] ambiguïté entière
[Termes IGN] correction ionosphérique
[Termes IGN] erreur systématique
[Termes IGN] mesurage de phase
[Termes IGN] phase GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision centimétrique
[Termes IGN] signal GLONASS
[Termes IGN] teneur totale en électrons
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) The precise point positioning (PPP) methodology allows for cm-level positioning accuracies using a single GNSS receiver, through careful modelling of all error sources affecting the signals. Adoption of PPP in several applications is however muted due to the time required for solutions to converge or re-converge to their expected accuracy, which regularly exceeds 30 minutes for a moving receiver. In an attempt at solving the convergence issues associated with PPP, three aspects were investigated.
First, signal tracking interruptions are typically associated with integer discontinuities in carrier-phase measurements, often referred to as a cycle slips. A refined method for detecting and correcting cycle slips was thus developed, in which all error sources affecting the observations are either modelled or estimated. Application of this technique allows for instantaneous cycle-slip correction, meaning that continuous PPP solutions can be obtained even in the presence of short losses of lock on satellites.
Second, external information on the ionosphere allows for reduced convergence times, but consistency must be observed in the functional model. A new technique, termed integer levelling, was thus developed to generate ionospheric delay corrections compatible with PPP based on the decoupled-clock model. Depending on the inter-station distances in the network providing ionospheric corrections, instantaneous cm-level accuracies can be obtained in PPP.
Third, processing of GLONASS signals is more problematic than GPS due to frequency division multiple access, leading to inter-frequency carrier-phase and code biases. A novel approach for the estimation of such biases was then proposed and facilitates processing of mixed receiver types. It also allows for undifferenced GLONASS ambiguity resolution based on a heterogeneous network of stations, the first demonstration of such an approach, and therefore has the potential to further reduce PPP convergence times.
This research also emphasized potential benefits of integer-levelled observations for improved ionosphere monitoring. The main justifications for adopting this approach are: a reduction in the determination of slant total electron content errors, a simplification in the GLONASS processing strategy, its applicability in real time, and the generation of satellite biases required for the use of ionospheric constraints in PPP with ambiguity resolution.Note de contenu : CH. 1 INTRODUCTION
1.1 Background
1.2 Objectives, Methodology, and Contributions
1.3 Dissertation Outline
CH. 2 IMPROVING REAL-TIME KINEMATIC PPP WITH INSTANTANEOUS CYCLE-SLIP CORRECTION
2.1 Introduction
2.2 Time-Differenced Functional Model
2.3 Time-Differenced Adjustment Process
2.4 Cycle-Slip Correction Procedure
2.5 PPP Solution Update
2.6 Processing Results
2.7 Further Discussions
2.8 Summary, Conclusions, and Future Work
CH. 3 MITIGATING THE IMPACTS OF IONOSPHERIC CYCLE SLIPS ON GNSS OBSERVATIONS
3.1 Introduction
3.2 Cycle-Slip Detection and Estimation
3.3 Integer Least-Squares Theory
3.4 Stochastic Analysis
3.5 Experimental Results
3.6 Conclusion
CH. 4 MONITORING THE IONOSPHERE USING INTEGER-LEVELLED GPS MEASUREMENTS
4.1 Introduction
4.2 Standard Levelling Procedure
4.3 Integer-Levelling Procedure
4.4 Slant TEC Evaluation
4.5 VTEC Evaluation
4.6 Conclusion
CH. 5 GLOBAL AND REGIONAL IONOSPHERIC CORRECTIONS FOR FASTER PPP CONVERGENCE
5.1 Introduction
5.2 The Decoupled-Clock Model (DCM)
5.3 The Extended Decoupled-Clock Model (EDCM)
5.4 Integer Levelling
5.5 Analyzing the Accuracy of Slant Ionospheric Corrections
5.6 PPP with Global Ionospheric Corrections
5.7 Regional Ionospheric Corrections for PPP with Ambiguity Resolution
5.8 Conclusion
CH. 6 GLONASS AMBIGUITY RESOLUTION OF MIXED RECEIVER TYPES WITHOUT EXTERNAL CALIBRATION
6.1 Introduction
6.2 Defining Minimum Constraints
6.3 Datum Transformation
6.4 Estimation of GLONASS Inter-frequency Code Biases
6.5 Proof of Concept
6.6 Conclusion
CH. 7 CONCEPTS FOR UNDIFFERENCED GLONASS AMBIGUITY RESOLUTION
7.1 Introduction
7.2 Estimating Inter-Frequency Biases
7.3 Ambiguity Resolution in the Presence of Biases
7.4 Application of Concepts
7.5 Characteristics of IFCBs
7.6 Melbourne-Wübbena Satellite Biases
7.7 Conclusion
CH. 8 CONCLUSION
8.1 Summary
8.2 Recommendations
8.3 Putting it All TogetherNuméro de notice : 14916 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : PhD : Geodesy and Geomatics Engineering : University of New Brunswick : 2014 En ligne : http://www2.unb.ca/gge/Pubs/TR294.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76904 Calibration of the clock-phase biases of GNSS networks: the closure-ambiguity approach / A. Lannes in Journal of geodesy, vol 87 n° 8 (August 2013)PermalinkAmbiguity resolution for triple-frequency geometry-free and ionosphere-free combination tested with real data / K. Wang in Journal of geodesy, vol 87 n° 6 (June 2013)PermalinkThe affine constrained GNSS attitude model and its multivariate integer least-squares solution / Peter J.G. Teunissen in Journal of geodesy, vol 86 n° 7 (July 2012)PermalinkPermalinkFast GNSS ambiguity resolution as an ill-posed problem / Lard Erik Sjöberg in Journal of geodesy, vol 84 n° 11 (November 2010)PermalinkLevel Crossing Rate Estimation (LCRE): a new technique for finding GNSS carrier-to-noise ratios / Elena Simona Lohan in Inside GNSS, vol 5 n° 6 (September 2010)PermalinkGNSS three carrier ambiguity resolution using ionosphere-reduced virtual signals / Y. Feng in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkGalileo down to the millimeter: analyzing a GIOVE-A-B double difference / Christian Tiberius in Inside GNSS, vol 3 n° 6 (September 2008)PermalinkThe Bayesian detection of discontinuities in a polynomial regression and its application to the cycle-slip problem / M.C. DE Lacy in Journal of geodesy, vol 82 n° 9 (September 2008)PermalinkFirst results of DORIS data analysis at Geodetic Observatory Pecný / Petr Štěpánek in Journal of geodesy, vol 80 n° 8-11 (November 2006)Permalink