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Precise relative positioning of formation flying spacecraft using GPS / R. Kroes (2006)
Titre : Precise relative positioning of formation flying spacecraft using GPS Type de document : Monographie Auteurs : R. 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 : Acknowledgements
Important Acronyms
Summary
Samenvatting (Summary in Dutch)
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 outlook
A Integer Ambiguity Estimation
B Lower boundary for the bootstrapping success rate
BibliographyNuméro de notice : 15179 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie 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 Le point sur les traitements de données GNSS en réseau pour un positionnement centimétrique temps réel de meilleure qualité / Romain Legros in XYZ, n° 105 (décembre 2005 - février 2006)
[article]
Titre : Le point sur les traitements de données GNSS en réseau pour un positionnement centimétrique temps réel de meilleure qualité Type de document : Article/Communication Auteurs : Romain Legros, Auteur ; F. Molle, Auteur ; N. Balard, Auteur Année de publication : 2005 Article en page(s) : pp 51 - 58 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] double différence
[Termes IGN] interpolation
[Termes IGN] perturbation ionosphérique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement par GPS
[Termes IGN] précision centimétrique
[Termes IGN] réfraction atmosphérique
[Termes IGN] temps réel
[Termes IGN] traitement de données GNSSRésumé : (Auteur) Depuis les années 80 et la mise en place du système GPS, les recherches dans le domaine du radiopositionnement par méthodes GNSS n'ont cessé de s'étendre et il est aujourd'hui possible de se positionner en temps réel avec une précision centimétrique de manière totalement transparente en traitant les données d'observation en réseau, afin de résoudre de manière satisfaisante la majorité des problèmes rencontrés en mode RTX. D'une manière générale, il s'agit de modéliser les erreurs spatialement corrélées (ionosphère, troposphère et éphémérides) sur chaque station avant de mettre en place des modèles de propagation en réseau (plans, polynômes ou modèles d'interpolation plus ou moins complexes) et de diffuser les données nécessaires aux utilisateurs (corrections et/ou observations) pour qu'ils puissent se positionner par double différence avec la précision escomptée suivant diverses approches. L'enjeu est de taille puisqu'il s'agit, au moment où plusieurs réseaux sont en passe de couvrir le territoire (ORPHEON, TERIA, etc.), de démocratiser l'utilisation de l'information géographique en favorisant son accès. Numéro de notice : A2005-485 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27621
in XYZ > n° 105 (décembre 2005 - février 2006) . - pp 51 - 58[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 112-05041 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Ionospheric modeling: the key to GNSS ambiguity resolution / T. Richert in GPS world, vol 16 n° 6 (June 2005)
[article]
Titre : Ionospheric modeling: the key to GNSS ambiguity resolution Type de document : Article/Communication Auteurs : T. Richert, Auteur ; Naser El-Sheimy, Auteur Année de publication : 2005 Article en page(s) : pp 35 - 40 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] diffusion du rayonnement
[Termes IGN] Global Navigation Satellite System
[Termes IGN] modèle ionosphérique
[Termes IGN] précision des données
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] propagation ionosphérique
[Termes IGN] résolution d'ambiguïtéRésumé : (Editeur) The GPS carrier-phase observable is more than 100 times more precise than the code-based pseudorange observable. Unfortunatly, it is also ambigous. If we want to use the carrier phase as a range measurement in positioning or navigation, we must account somehow for the unknown integer number of cycles or turns of phase in the initial measurement when a GPS receiver locks onto satellite's L1 or L2 signal carrier. Mathematicians, scientists and engineering have developed clever techniques for helping these integer ambiguities either in real time or in post-processing collected data. However, the success of these techniques in correctly determining the ambiguities depends on several factors including wether a point or relative positioning technique is employed, the length of the baseline in relative positioning, and how well a variety of errors afflicting the measurements can be mitigated. One source of such errors is the ionosphere. In this month's column, we examine how ionospheric modeling helps in the resolution of carrier-phase ambiguities and how the rate of success in correctly determining the ambiguities will be much improved when GPS observations are combined with those of the future Gallileo system. Numéro de notice : A2005-279 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27415
in GPS world > vol 16 n° 6 (June 2005) . - pp 35 - 40[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-05061 SL Revue Centre de documentation Revues en salle Disponible GPS-Anwendungen in der Sportwissenschaft / T. Blumenbach (2005)
Titre : GPS-Anwendungen in der Sportwissenschaft : Entwicklung eines Messverfahrens für das Skispringen Titre original : [Emploi du GPS dans la science du sport : développement d'un procédé de mesure pour le saut en ski] Type de document : Thèse/HDR Auteurs : T. Blumenbach, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2005 Collection : DGK - C Sous-collection : Dissertationen num. 591 Importance : 74 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-5030-3 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] GPS en mode cinématique
[Termes IGN] mesurage de phase
[Termes IGN] phase GPS
[Termes IGN] positionnement par GPS
[Termes IGN] précision centimétrique
[Termes IGN] récepteur GPS
[Termes IGN] sportIndex. décimale : 30.80 Applications diverses de géodésie spatiale Résumé : (Auteur) Carrier phase based GPS applications with centimeter accuracy have become more popular over the last years, not only in surveying. First investigations are accomplished in sports sciences as well. However, most geodetic GPS equipment is too large and too heavy for attaching it at the athletes body. Using the potential of miniaturized electronics, a special GPS receiver for ski jumping was developed. The hardware could be integrated completely into a common jumping helmet. Striving to an ideal measurement system with no influence on the athlete activities only little adverse effects remain on the athletes using the GPS-helmet. The topography of jumping hills results in a more or less shadowing of the GPS satellite signals. Not all jumping hills are applicable for GPS measurements. Measurement campaigns need to be well planned considering satellite constellation issues. Centimeter accuracy requires successful integer ambiguity fixing. Common algorithms assume uninterrupted signal reception over a sufficient long time. But the 10-20 seconds for an attempt, take-off, flight and landing are not long enough. Thus a laser light barrier array was developed. It determines position and time of the GPS-helmet during athletes take-off from the ramp. This information enables the ambiguity fixing and enhances accuracy and reliability of the solution, even for short GPS measurement segments. The system was successfully tested during some training sessions of german ski jumpers. It was shown which informations can be derived from positions and velocities for several phases of a jump. Numéro de notice : 13275 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54954 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13275-01 30.80 Livre Centre de documentation Géodésie Disponible 13275-02 30.80 Livre Centre de documentation Géodésie Disponible The GNSS integer ambiguities / S. Verhagen (2005)
Titre : The GNSS integer ambiguities : estimation and validation Type de document : Monographie Auteurs : S. Verhagen, Auteur Editeur : Delft : Netherlands Geodetic Commission NGC Année de publication : 2005 Collection : Netherlands Geodetic Commission Publications on Geodesy, ISSN 0165-1706 num. 58 Importance : 170 p. Format : 17 x 24 cm ISBN/ISSN/EAN : 978-90-6132-290-0 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] axiome de Bayes
[Termes IGN] code GPS
[Termes IGN] contrôle qualité
[Termes IGN] distribution de Student
[Termes IGN] distribution, loi de
[Termes IGN] estimation statistique
[Termes IGN] Galileo
[Termes IGN] Global Navigation Satellite System
[Termes IGN] Global Orbitography Navigation Satellite System
[Termes IGN] Global Positioning System
[Termes IGN] mesurage de phase
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle fonctionnel
[Termes IGN] modèle stochastique
[Termes IGN] phase
[Termes IGN] propagation du signal
[Termes IGN] qualité des données
[Termes IGN] résidu
[Termes IGN] résolution d'ambiguïtéIndex. décimale : 30.61 Systèmes de Positionnement par Satellites du GNSS Résumé : (Auteur) Fast and high precision relative positioning with a Global Navigation Satellite System (GNSS) is only possible by using the very precise carrier phase measurements. However, these carrier phases are ambiguous by an unknwon number of cycles. The knowledge that the ambiguities are integer-valued has been exploited in the past 15 years for the development of integer ambiguity resolution algorithms. Once the ambiguities are fixed to their integer values, the carrier phase measurements start to act as if they were very precise pseudorange measurements. [...] Nowadays, the non-trivial problem of integer ambiguity estimation can be considered solved. However, a parameter estimation theory is not complete without the appropriate measures to validate the solution. [...] Obviously, validation of the integer ambiguity solution is still an open problem. Two approaches are investigated here. The first method uses a new ambiguity estimator, the Best Integer Equivariant (BIE) estimator. [...] It was shown that the BIE estimator significantly outperforms the float or fixed solution only in a limited number of cases. Therefore, another new class of integer estimators is investigated : the class of Integer Aperture (IA) estimators. [...] IA estimation has several important advantages. [...] Finally, it is shown that the popular ratio test perform almost as good as the optimal IA estimator if the fixed fail rate approach is used. [...] Note de contenu : Summary
Notation and symbols
Acronyms
1 Introduction
1.1 Background
1.2 Objectives and contribution of this work
1.3 Outline
2 GNSS observation model and quality control
2.1 Global Navigation Satellite Systems
2.2 GNSS observation equations
2.3 GNSS functional model
2.4 GNSS stochastic model
2.5 Least-squares estimation and quality control
3 Integer ambiguity resolution
3.1Integer estimation
3.2Quality of the integer ambiguity solution
3.3 The ambiguity residuals .
3.4 Quality of the fixed baseline estimator
3.5 Validation of the fixed solution
3.6 The Bayesian approach
4 Best Integer Equivariant estimation
4.1 The BIE estimator
4.2 Approximation of the BIE estimator
4.3 Comparison of the float, fixed, and BIE estimators .
4.4 Summary . .
5 Integer Aperture estimation
5.1 Integer Aperture estimation
5.2 Ellipsoidal integer aperture estimation
5.3 Ratio test, difference test and projector test
5.4 Integer Aperture Bootstrapping and LeastSquares .
5.5 Penalized Integer Aperture estimation
5.6 Optimal Integer Aperture estimation
5.7 Implementation aspects
5.8 Comparison of the different IA estimators
5.9 Performance of IA estimation
5.10 Summary
6 Conclusions and recommendations
6.1 Integer estimation and validation
6.2 Quality of the baseline estimators
6.3 Reliability of the results
6.4 Bias robustness
A Mathematics and statistics
A.1 Kronecker product
A.2 Parameter distributions
A.3 Numerical root finding methods
B Simulation and examples
B.1 Simulation
B.2 Examples.
C Theory of BlE estimation
C.1 Integer equivariant ambiguity estimation
C.2 Integer equivarlant unbiased ambiguity estimation
C.3 Best integer equivariant unbiased ambiguity estimation
C.4 Best integer equivariant unbiased baseline estimation
D Implementation aspects of IALS estimationNuméro de notice : 15134 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55070 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15134-01 30.61 Livre Centre de documentation Géodésie Disponible 15134-02 30.61 Livre Centre de documentation Géodésie Disponible GPS satellite surveying / Alfred Leick (2004)PermalinkPhase ambiguity determination for the positioning of interferometric SAR data / A. Sowter in Photogrammetric record, vol 18 n° 104 (December 2003 - February 2004)PermalinkAmélioration de la précision de la localisation différentielle temps réel par mesure de phase des systèmes GNSS / Stéphane Durand (2003)PermalinkGPS : Theory, algorithms and applications / Guochang Xu (2003)PermalinkZur Bestimmung der GPS-Phasenmehrdeutigkeiten in großräumigen Netzen / K. Wienholz (2003)Permalink0,99999999 confidence ambiguity resolution with GPS and Galileo / Christian Tiberius in GPS solutions, vol 6 n° 1-2 (November 2002)PermalinkStochastic assessment of GPS carrier phase measurements for precise static relative positioning / J. Wang in Journal of geodesy, vol 76 n° 2 (February 2002)PermalinkApplication des méthodes de résolution d'ambigüités sur la mesure de phase GPS à l'approche de précision / J.P. Chauveau (2002)PermalinkFast precise GPS positioning in the presence of ionospheric delays / Dennis Odijk (2002)PermalinkStatistische Untersuchung ganzzahliger und reellwertiger unbekannter Parameter im GPS-Modell / B. Gundlich (2002)Permalink