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A single-receiver geometry-free approach to stochastic modeling of multi-frequency GNSS observables / Baocheng Zhang in Journal of geodesy, vol 94 n°4 (April 2020)
Titre : A single-receiver geometry-free approach to stochastic modeling of multi-frequency GNSS observables Type de document : Article/Communication Auteurs : Baocheng Zhang, Auteur ; Pengyu Hou, Auteur ; Teng Liu, Auteur ; Yunbin Yuan, Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse de variance
[Termes IGN] corrélation croisée normalisée
[Termes IGN] corrélation temporelle
[Termes IGN] fréquence multiple
[Termes IGN] méthode des moindres carrés
[Termes IGN] méthode robuste
[Termes IGN] modèle stochastique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] récepteur
[Termes IGN] traitement de données GNSS
[Termes IGN] trajet multipleRésumé : (auteur) The proper choice of stochastic model is of great importance to global navigation satellite system (GNSS) data processing. Whereas extensive investigations into stochastic modeling are mainly based on the relative (or differential) method employing zero and/or short baselines, this work proposes an absolute method that relies upon a stand-alone receiver and works by applying the least-squares variance component estimation to the geometry-free functional model, thus facilitating the characterization of stochastic properties of multi-frequency GNSS observables at the undifferenced level. In developing the absolute method, special care has been taken of the code multipath effects by introducing ambiguity-like parameters to the code observation equations. By means of both the relative and absolute methods, we characterize the precision, cross and time correlation of the code and phase observables of two newly emerging constellations, namely the Chinese BDS and the European Galileo, collected by a variety of receivers of different types at multiple frequencies. Our first finding is that so far as the precision is concerned, the absolute method yields nearly the same numerical values as those derived by the zero-baseline-based relative method. However, the two methods give contradictory results with regard to the cross correlation, which is found (not) to occur between BDS phase observables when use has been made of the relative (absolute) method. Our explanation to this discrepancy is that the cross correlation found in the relative method originates from the parts (antenna, cable, low noise amplifier) shared by two receivers creating a zero baseline. The time correlation is only of significance when the multipath effects are present, as is the case with the short-baseline-based relative method; this correlation turns out to be largely weaker (or ideally absent) in the absolute (or zero-baseline-based relative) method. Moreover, with the absolute method, the stochastic properties determined for two receivers of the same type but subject to different multipath effects are virtually the same. We take this as a convincing evidence that the absolute method is robust against multipath effects. Hence, the absolute method proposed in the present work represents a promising complement to the relative method and appears to be particularly beneficial to GNSS positioning, navigation and timing technologies based on the undifferenced observables, typically the precise point positioning. Numéro de notice : A2020-160 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01366-8 date de publication en ligne : 09/03/2020 En ligne : https://doi.org/10.1007/s00190-020-01366-8 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94817
in Journal of geodesy > vol 94 n°4 (April 2020)[article]
Titre : Ground-based phase wind-up and its application in yaw angle determination Type de document : Article/Communication Auteurs : M. Cai, Auteur ; W. Chen, Auteur ; D. Dong, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 757 – 772 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GNSS
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision du positionnement
[Termes IGN] récepteurRésumé : (auteur) Ground-based phase wind-up effect (GPWU) is caused by the rotation of receiving antenna. It had been studied and applied in rapidly rotation platforms, such as sounding rocket, guided missile and deep space exploration. In Global Navigation Satellite System high accuracy positioning applications, however, most studies treated it as an error source and focused on eliminating this effect in Precision Point Positioning and Real Time Kinematic (RTK) positioning. The GPWU effect is also sensitive to the rotational status of the antenna, in particular the yaw angle variations. In this paper we explore the feasibility of yaw angle determination of relatively slow rotation platforms based on the GPWU effect. We use the geometry-free carrier phase observations from a RTK base and a moving station receivers to estimate the cumulative yaw angle of the moving platform. Several experiments, including rotating platform tests, vehicle and shipborne tests were carried out. The cumulative errors of rotating platform tests are under 0.38∘, indicating good long-term accuracy of the GPWU determined yaw angle. But the RMS are in a range of 11.98∘and 17.39∘, indicating the errors, such as multipath effect, are not negligible and should be further investigated. The RMS of vehicle and shipborne tests using a base station of 9–11 km are 24.77∘ and 23.66∘. In order to evaluate the influence of the differential ionospheric delay, another vehicle test was carried out using a base station located less than 1 km to the vehicle. The RMS reduces to 15.11∘, which gains 39.00 % improvement than before, and demonstrates that the differential ionospheric delay even from a few kilometers long baseline still cannot be neglected. These tests validate the feasibility of GPWU for real-time yaw angle determination. Since this method is able to determine the yaw angle with a minimum one satellite, such a unique feature provides potential applications for attitude determination in the environment with poor sky visibility. Numéro de notice : A2016-506 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0908-7 date de publication en ligne : 10/05/2016 En ligne : https://doi.org/10.1007/s00190-016-0908-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81530
in Journal of geodesy > vol 90 n° 8 (August 2016) . - pp 757 – 772[article]
Titre : Estimation of multi-constellation GNSS observation stochastic properties using single receiver single satellite data validation method Type de document : Article/Communication Auteurs : A. El-Mowafy, Auteur Année de publication : 2015 Article en page(s) : pp 99 - 108 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] constellation GNSS
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement par Galileo
[Termes IGN] positionnement par GLONASS
[Termes IGN] positionnement par GPS
[Termes IGN] positionnement statique
[Termes IGN] récepteur
[Termes IGN] validation des données
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) The single receiver single satellite validation method is a technique that screens data from each satellite independently to detect and identify faulty observations. A new method for estimation of the stochastic properties of multi-constellation GNSS observation is presented utilising parameters of this validation method. Agreement of the characteristics of the validation statistics with theory is used as the criterion to select the best precision of the observations, spectral density and correlation time of the unknowns. A curve fitting approach in an iterative scheme is employed. The method is applicable to any GNSS with any arbitrary number of frequencies. Demonstration of the method results and performance is given using multiple-frequency data from GPS, GLONASS and Galileo in static and kinematic modes. Numéro de notice : A2015-957 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1179/1752270614Y.0000000100 En ligne : https://doi.org/10.1179/1752270614Y.0000000100 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79942
in Survey review > vol 47 n° 341 (March 2015) . - pp 99 - 108[article]Effects on the geodetic-VLBI observables due to polarization leakage in the receivers / A. Roy (2012)
Titre : Effects on the geodetic-VLBI observables due to polarization leakage in the receivers Type de document : Thèse/HDR Auteurs : A. Roy, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2012 Collection : DGK - C Sous-collection : Dissertationen num. 681 Importance : 160 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-5093-8 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] données ITGB
[Termes IGN] interférométrie à très grande base
[Termes IGN] polarisation
[Termes IGN] récepteurRésumé : (Auteur) Geodetic VLBI delivers baseline length and Earth orientation parameter measurements, which offer the most viable and precise way to study Earth crustal and core dynamics and to support space navigation. The precision of these geodetic and astrometric measurements is degraded by instrumental errors of which polarization leakage is one of the larger. Its effect can be corrected in the data provided one knows the leakage characteristics of the stations. In this work I introduce the concept of polarization, why it needs to be considered in the geodetic analysis and present a VLBI experiment that measured the polarization leakage at 16 geodetic and VLBA stations over the frequency range 8212.99 MHz to 8932.99 MHz and 2225.99 MHz to 2365.99 MHz. I describe resulting polarization leakage measurements and the algorithm that was implemented to correct for their effect on the geodetic delay measurables. I applied the correction for polarization leakage to a routine geodetic VLBI experiment and check for the resulting improvement. Prom the measured leakage terms, one would expect polarization leakage to affect the group delay measurements by 0.5 ps to 7 ps, depending on the stations involved in the baseline. This proved to be below the statistical noise in a single VLBI experiment and so the improvement from the correction could not be detected. Polarization leakage was found, unexpectedly, not the dominant source of non-closing errors. Numéro de notice : 14618 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62669 Documents numériques
en open access
14618_dgk-c-681_roy.pdfAdobe Acrobat PDF
Titre : GPS + LORAN-C: performance analysis of an integrated tracking system Type de document : Article/Communication Auteurs : J. Carroll, Auteur Année de publication : 2006 Article en page(s) : pp 40 - 47 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] GPS assisté pour la navigation (technologies)
[Termes IGN] intégration de données
[Termes IGN] LORAN (système)
[Termes IGN] navigation à l'estime
[Termes IGN] performance
[Termes IGN] positionnement par GPS
[Termes IGN] récepteurRésumé : (Editeur) Before GPS, even before satellites, there was LOng RAnge Navigation, or LORAN. Using terrestrial radio transmitters, it was developed during World War II for aircraft navigation. The wartime system evolved by the mid-1950s into the present day 100 kHz LORAN-C system. LORAN's standard principle of op-eration is hyperbolic positioning. A receiver measures the difference in times of arrival of pulses transmitted by a chain of three to six synchronized stations sep--arated by hundreds of kilometers. The time-difference measurement derived from the signals of two stations, when multiplied by the speed of propagation of the signals, forms a line of position (LOP); the receiver could be anywhere on this line and give the same measurement. The geometrical form of this LOP is a hyperbola. Measurements using a third station provide an-other hyperbola, which intersects the first at the position of the receiver. There are many LORAN chains around the globe.
The LORAN system is being modernized to enhance its accuracy, integrity, availability, and continuity. Vacuum-tube transmitters are being replaced with solid-state designs and new primary frequency standards are being installed at transmitting stations. Manufacturers have developed compact LORAN receivers able to track multiple transmitters simultaneously and to automatically apply propagation bias corrections. Some receivers are integrated with GPS or other sensors. Receivers also feature improved antenna designs. Collectively, these improvements are known as Enhanced LORAN or eLORAN for short. Additionally, LORAN signals can be used to convey differential GPS corrections. Such a system is already operational in Europe. Supported by the Coast Guard and the Federal Aviation Administration in the United States, a goal of eLORAN is to provide non-precision approach for aviation users and harbor entrance and approach for marine users. Land users will benefit, too. Since LORAN has different signal characteristics from those of GPS, it can be used in locations where GPS cannot by itself or in conjunction with GPS and other sensors. In this month's column, we look at a system that combines eLORAN with GPS and dead reckoning to overcome some of the problems in navigating in big cities. Copyright Questex Media Group IncNuméro de notice : A2006-567 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28290
in GPS world > vol 17 n° 7 (July 2006) . - pp 40 - 47[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 067-06071 RAB Revue Centre de documentation En réserve 3L Disponible PermalinkPermalinkPermalinkPermalinkPermalinkPermalinkPermalinkSymposium national sur la localisation en mer, Tome 1. Problèmes géodésiques liés à la localisation en mer / Service hydrographique et océanographique de la marine (1980)
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