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Real-time cycle-slip detection and repair for BeiDou triple-frequency undifferenced observations / Y.-F. Yao in Survey review, vol 48 n° 350 (September 2016)
[article]
Titre : Real-time cycle-slip detection and repair for BeiDou triple-frequency undifferenced observations Type de document : Article/Communication Auteurs : Y.-F. Yao, Auteur ; J.-X. Gao, Auteur ; J. Wang, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 367 - 375 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] détection d'anomalie
[Termes IGN] glissement de cycle
[Termes IGN] phase
[Termes IGN] positionnement par BeiDou
[Termes IGN] récepteur trifréquence
[Termes IGN] signal BeiDou
[Termes IGN] temps réelRésumé : (auteur) A new method of real-time cycle-slip detection and repair for BeiDou navigation satellite system (BDS) triple-frequency undifferenced observations is proposed. The method, which is based on code–phase and geometry-free phase combinations, composes linearly independent combination observations to uniquely determine the cycle-slip of original frequency phase observations in two independent steps. First, two extra-wide lane (EWL) code–phase combinations are utilised to determine the EWL combination cycle-slips. The sum of the carrier phase combination coefficients is zero. Second, the geometry-free phase combination with a non-zero sum of combination coefficients composes linearly independent combination observations with two code–phase combinations. Ionospheric delay variance systematic deviation is corrected with several previous carrier-phase observations without cycle-slip, which seriously affect the accuracy of the geometry-free phase combination observations. The BDS triple-frequency carrier-phase and code observations of different satellite types at 30 s sampling interval, which involve increased active ionospheric conditions in 1 day, are utilised to test the method. Results show that the proposed method can efficiently detect and accurately repair any cycle-slip combinations in real-time for different satellite types under active ionospheric conditions. No erroneous and leakage judgments are observed in the test. Numéro de notice : A2016-642 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/00396265.2015.1133518 En ligne : https://doi.org/10.1080/00396265.2015.1133518 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81847
in Survey review > vol 48 n° 350 (September 2016) . - pp 367 - 375[article]A new method to improve the performance of multi-GNSS pseudorange positioning in signal-degraded environment / Hui Liu in Advances in space research, vol 58 n° 4 (August 2016)
[article]
Titre : A new method to improve the performance of multi-GNSS pseudorange positioning in signal-degraded environment Type de document : Article/Communication Auteurs : Hui Liu, Auteur ; Longwei Xu, Auteur ; Bao Shu, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 577 - 586 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] interopérabilité
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] système de positionnement par satellites
[Termes IGN] visibilitéRésumé : (auteur) There are two existing multi-GNSS positioning methods, (1) separate receiver clock parameter is set for each constellation, (2) estimating intersystem biases (ISBs) in advance to obtain position solutions with only four unknowns. The former is the regular method and its unknowns include three receiver-coordinate parameters and several receiver clock parameters (depend on the number of participant constellations), so that it may disable when few satellites belonging to different GNSS are in view. The latter is one workable way to obtain position solution with only four visible satellites. In addition to the disabled regular method, the positioning results by the ISB-corrected method are often unsatisfactory for navigation users in signal-degraded environment. Both the deviation of ISB-solutions and the remaining measurement errors of the need corrected observations are factors to degrade location precision. Apart from these, fewer visible satellites usually cause a low robustness of the positioning model, which cause the negative influence of various errors is amplified. Based on the variation of various measurement errors, we propose a new ISSB-corrected method with observations corrected by corresponding satellite-dependent parameters. The new parameter contains the difference of time scales, hardware delays and uncorrected measurement errors between the corresponding satellite and reference, in other words, it can synthetically consider measurement errors and the ISB. By the ISSB-corrected method, we not only achieve positioning solutions with four satellites, but also significantly reduce the accuracy loss. Many experiments are conducted to present the superiority of the ISSB-corrected method. In open-area, the accuracies of regular and ISB-corrected methods are nearly equal. Apart from a similar accuracy in horizontal, the accuracy is improved by approximate 10% in up direction with respect to the two existing methods. Given the high redundancy of model in open-area, the new method may not improve the accuracy remarkably. However, it can make great contributions in signal-degraded environments. In order to compare the performance of ISB- and ISSB-corrected methods in environment with limited visible satellites, we simulate several scenarios (different satellites participant or various receivers) with only four participant satellites in the positioning solution. By the ISSB-corrected method, the 3D RMS of positioning results with four satellites is about 15 m, while it is usually worse than 25 m for the ISB-corrected method. In an urban vehicular test, the horizontal positioning error of the ISSB-corrected method is less than 20 m; and the ISB-corrected method may reach up to 70 m. Numéro de notice : A2016-592 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2016.05.016 En ligne : http://dx.doi.org/10.1016/j.asr.2016.05.016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81748
in Advances in space research > vol 58 n° 4 (August 2016) . - pp 577 - 586[article]Estimation of satellite antenna phase center offsets for Galileo / Peter Steigenberger in Journal of geodesy, vol 90 n° 8 (August 2016)
[article]
Titre : Estimation of satellite antenna phase center offsets for Galileo Type de document : Article/Communication Auteurs : Peter Steigenberger, Auteur ; M. Fritsche, Auteur ; Rolf Dach, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : Pages 773 - 785 Note générale : bibliograohie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne Galileo
[Termes IGN] centre de phase
[Termes IGN] compensation
[Termes IGN] orbitographie
[Termes IGN] positionnement par GNSS
[Termes IGN] signal Galileo
[Termes IGN] soleil (étoile)Résumé : (auteur) Satellite antenna phase center offsets for the Galileo In-Orbit Validation (IOV) and Full Operational Capability (FOC) satellites are estimated by two different analysis centers based on tracking data of a global GNSS network. The mean x- and y-offsets could be determined with a precision of a few centimeters. However, daily estimates of the x-offsets of the IOV satellites show pronounced systematic effects with a peak-to-peak amplitude of up to 70 cm that depend on the orbit model and the elevation of the Sun above the orbital plane. For the IOV y-offsets, no dependence on the orbit model exists but the scatter strongly depends on the elevation of the Sun above the orbital plane. In general, these systematic effects are significantly smaller for the FOC satellites. The z-offsets of the two analysis centers agree within the 10–15 cm level, and the time series do not show systematic effects. The application of an averaged Galileo satellite antenna model obtained from the two solutions results in a reduction of orbit day boundary discontinuities by up to one third—even if an independent software package is used. Numéro de notice : A2016-505 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0909-6 En ligne : http://dx.doi.org/10.1007/s00190-016-0909-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81529
in Journal of geodesy > vol 90 n° 8 (August 2016) . - Pages 773 - 785[article]Galileo and the Brexit effect : Tension grows over the public regulated service / Tim Reynolds in GPS world, vol 27 n° 8 (August 2016)
[article]
Titre : Galileo and the Brexit effect : Tension grows over the public regulated service Type de document : Article/Communication Auteurs : Tim Reynolds, Auteur Année de publication : 2016 Article en page(s) : pp 11 - 12 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] GalileoNuméro de notice : A2016-595 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81773
in GPS world > vol 27 n° 8 (August 2016) . - pp 11 - 12[article]Ground-based phase wind-up and its application in yaw angle determination / M. Cai in Journal of geodesy, vol 90 n° 8 (August 2016)
[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]The international GNSS monitoring and assessment service in a multi-system environment / Echoda Ngbede Joshua Ada in Inside GNSS, vol 11 n° 4 (July - August 2016)PermalinkAssessment of vertical TEC mapping functions for space-based GNSS observations / Jiahao Zhong in GPS solutions, vol 20 n° 3 (July 2016)PermalinkBenefits of the third frequency signal on cycle slip correction / Xiaohong Zhang in GPS solutions, vol 20 n° 3 (July 2016)PermalinkA closed-form formula to calculate geometric dilution of precision (GDOP) for multi-GNSS constellations / Yunlong Teng in GPS solutions, vol 20 n° 3 (July 2016)PermalinkA comparative analysis of measurement noise and multipath for four constellations: GPS, BeiDou, GLONASS and Galileo / Changsheng Cai in Survey review, vol 48 n° 349 (July 2016)PermalinkIdentifying a low-frequency oscillation in Galileo IOV pseudorange rates / Daniele Borio in GPS solutions, vol 20 n° 3 (July 2016)PermalinkThe development and performance of the VeraPhase antenna / Julien Hautcoeur in GPS world, vol 27 n° 7 (July 2016)PermalinkInter-signal correction sensitivity analysis : aperture-dependent delays induced by antenna anisotropy in modernized GPS dual-frequency navigation / Gary Okerson in Inside GNSS, vol 11 n° 3 (May - June 2016)PermalinkListening for RF noise : An analysis of pre-despreading GNSS interference detection techniques / Ali Jafarnia-Jahromi in Inside GNSS, vol 11 n° 3 (May - June 2016)PermalinkTesting impact of the strategy of VLBI data analysis on the estimation of Earth Orientation Parameters and station coordinates / Agata Wielgosz in Reports on geodesy and geoinformatics, vol 101 (June 2016)Permalink