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From RTK to PPP-RTK: towards real-time kinematic precise point positioning to support autonomous driving of inland waterway vessels / Xiangdong An in GPS solutions, vol 27 n° 2 (April 2023)
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Titre : From RTK to PPP-RTK: towards real-time kinematic precise point positioning to support autonomous driving of inland waterway vessels Type de document : Article/Communication Auteurs : Xiangdong An, Auteur ; Ralf Ziebold, Auteur ; Christoph Laas, Auteur Année de publication : 2023 Article en page(s) : n° 86 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] filtre de Kalman
[Termes IGN] navigation autonome
[Termes IGN] navigation fluviale
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Termes IGN] station GNSS
[Termes IGN] temps de convergenceRésumé : (auteur) PPP-RTK is Precise Point Positioning (PPP) using corrections from a ground reference network, which enables single-receiver users with integer ambiguity resolution thereby improving its performance. However, most of the PPP-RTK studies are investigated and evaluated in a static situation or a post-processing mode because of the complexity of implementation in real-time practical applications. Moreover, although PPP-RTK achieves a faster convergence than PPP, it typically needs 30 s or even longer to derive high-accuracy results. We have implemented a real-time PPP-RTK approach based on undifferenced observations and State-Space Representation corrections with a fast convergence of less than 30 s to support autonomous driving of inland waterway vessels. The PPP-RTK performances and their feasibility to support autonomous driving have been evaluated and validated in a real-time inland waterway navigation. It proves the PPP-RTK approach can realize a precise positioning of less than 10 cm in horizontal with a rapid convergence. The convergence time is within 10 s after a normal bridge passing and less than 30 s after a complicated bridge passing. Moreover, the PPP-RTK approach can be extended to outside of the GNSS station network. Even if the location is 100 km away from the border of the GNSS station network, the PPP-RTK convergence time after a bridge passing is also normally less than 30 s. We have realized the first automated entry into a waterway lock for a vessel supported by PPP-RTK and taken the first step toward autonomous driving of inland vessels based on PPP-RTK. Numéro de notice : A2023-156 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-023-01428-2 En ligne : https://doi.org/10.1007/s10291-023-01428-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102843
in GPS solutions > vol 27 n° 2 (April 2023) . - n° 86[article]A unified cycle-slip, multipath estimation, detection and mitigation method for VIO-aided PPP in urban environments / Bo Xu in GPS solutions, vol 27 n° 2 (April 2023)
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Titre : A unified cycle-slip, multipath estimation, detection and mitigation method for VIO-aided PPP in urban environments Type de document : Article/Communication Auteurs : Bo Xu, Auteur ; Shoujian Zhang, Auteur ; Kaifa Kuang, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 59 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] filtre de Kalman
[Termes IGN] glissement de cycle
[Termes IGN] milieu urbain
[Termes IGN] modèle stochastique
[Termes IGN] navigation autonome
[Termes IGN] navigation inertielle
[Termes IGN] odomètre
[Termes IGN] phase
[Termes IGN] positionnement ponctuel précis
[Termes IGN] signal GNSS
[Termes IGN] trajet multipleRésumé : (auteur) Accurate, continuous and reliable positioning is required in autonomous driving. The precise point positioning (PPP) technique, which can provide a global accurate positioning service using a single global navigation satellite system (GNSS) receiver, has attracted much attention. Nevertheless, due to the cycle slips and multipath effects in the GNSS signal, the performance of PPP is severely degraded in urban areas, which has a negative effect on the PPP/inertial navigation system (INS)/vision integrated navigation. Moreover, the carrier phase observations with un-modeled multipath cause false detection of small cycle slips and lead to deviation in the state variable estimation in PPP. Therefore, an effective cycle slip/multipath estimation, detection and mitigation (EDM) method is proposed. A clustering method is used to separate the cycle slips and multipath from the carrier phase observations aided by visual inertial odometry (VIO) positioning results. The influence of the carrier phase multipath on state variable estimation is reduced by adjusting the stochastic ambiguity model in the Kalman filter. The proposed EDM method is validated by vehicle experiments conducted in urban and freeway areas. Experimental results demonstrate that 0.2% cycle slip detection error is achieved by our method. Besides, the multipath estimation accuracy of EDM improves by more than 50% compared with the geometry-based (GB) method. Regarding positioning accuracy, the EDM method has a maximum of 72.2% and 63.2% improvement compared to traditional geometry-free (GF) and GB methods. Numéro de notice : A2023-124 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-023-01396-7 Date de publication en ligne : 17/01/2023 En ligne : https://doi.org/10.1007/s10291-023-01396-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102501
in GPS solutions > vol 27 n° 2 (April 2023) . - n° 59[article]Enabling RTK positioning under jamming: Mitigation of carrier-phase distortions induced by blind spatial filtering / Tobias Bamberg in Navigation : journal of the Institute of navigation, vol 70 n° 1 (Spring 2023)
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Titre : Enabling RTK positioning under jamming: Mitigation of carrier-phase distortions induced by blind spatial filtering Type de document : Article/Communication Auteurs : Tobias Bamberg, Auteur ; A. Konovaltsev, Auteur ; Michael Meurer, Auteur Année de publication : 2023 Article en page(s) : n° 556 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] brouillage
[Termes IGN] compensation
[Termes IGN] erreur de phase
[Termes IGN] filtrage du bruit
[Termes IGN] filtrage du signal
[Termes IGN] interférence
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] signal GNSSRésumé : (auteur) New GNSS applications demand resilience against radio interference and high position accuracy. Separately, these demands can be fulfilled by multi-antenna systems using spatial filtering and carrier-phase positioning algorithms like real-time kinematic (RTK), respectively. However, combining these approaches encounters a severe issue: The spatial filtering induces a phase offset into the measured carrier phase leading to a loss of position accuracy. This paper presents a new approach to compensate for the phase offset in a blind manner, (i.e., without knowing the antenna array radiation pattern or the direction of arrival of the signals). The proposed approach is experimentally validated in two jamming scenarios. One includes a jammer with increasing power and the other includes a moving jammer. The results demonstrate that the approach successfully compensates for the phase offset and, hence, allows for the combined use of RTK positioning and spatial filtering even under jamming. Numéro de notice : A2023-140 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.33012/navi.556 Date de publication en ligne : 09/08/2022 En ligne : https://doi.org/10.33012/navi.556 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102703
in Navigation : journal of the Institute of navigation > vol 70 n° 1 (Spring 2023) . - n° 556[article]Improved GPS-based single-frequency orbit determination for the CYGNSS spacecraft using GipsyX / Alex V. Conrad in Navigation : journal of the Institute of navigation, vol 70 n° 1 (Spring 2023)
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Titre : Improved GPS-based single-frequency orbit determination for the CYGNSS spacecraft using GipsyX Type de document : Article/Communication Auteurs : Alex V. Conrad, Auteur ; Penina Axelrad, Auteur ; Bruce J. Haines, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 565 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] données GRACE
[Termes IGN] étalonnage d'instrument
[Termes IGN] mesurage de phase
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] récepteur monofréquence
[Termes IGN] trajet multipleRésumé : (auteur) This paper presents methods for the precise orbit determination (POD) of a satellite in the CYGNSS constellation based on available single-frequency GPS code and carrier measurements. The contributions include the development and evaluation of procedures for single-frequency POD with GipsyX, improvement of CYGNSS orbit knowledge, and an assessment of its final accuracy. Ionospheric effects are mitigated using the GRAPHIC processing method, and spacecraft multipath effects are calibrated with an azimuth/elevation-dependent antenna calibration map. The method is demonstrated using comparable data from the GRACE mission, from which we infer the expected accuracy of the CYGNSS results. Processing more than 170 days of data from each mission, a 1σ CYGNSS orbit accuracy of 2.8 cm radial, 2.4 cm cross-track, and 6 cm in-track is demonstrated. We expect that achieving this level of performance will expand the set of future scientific investigations that can be undertaken using satellites equipped with single-frequency GNSS. Numéro de notice : A2023-141 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.33012/navi.565 Date de publication en ligne : 20/10/2022 En ligne : https://doi.org/10.33012/navi.565 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102708
in Navigation : journal of the Institute of navigation > vol 70 n° 1 (Spring 2023) . - n° 565[article]The importance of co-located VLBI Intensive stations and GNSS receivers / Christopher Dieck in Journal of geodesy, vol 97 n° 3 (March 2023)
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Titre : The importance of co-located VLBI Intensive stations and GNSS receivers Type de document : Article/Communication Auteurs : Christopher Dieck, Auteur ; Megan C. Johnson, Auteur ; Daniel S. MacMillan, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 21 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Hawaii (Etats-Unis)
[Termes IGN] interférométrie à très grande base
[Termes IGN] positionnement par ITGB
[Termes IGN] rapport signal sur bruit
[Termes IGN] récepteur GNSS
[Termes IGN] station GNSS
[Termes IGN] station VLBI
[Termes IGN] temps universel coordonnéRésumé : (auteur) Frequent, low-latency measurements of the Earth’s rotation phase, expressed as UT1−UTC critically support the current estimate and short-term prediction of this highly variable Earth orientation parameter (EOP). Very long baseline interferometry (VLBI) Intensive sessions provide the required data. However, the Intensive UT1−
UTC measurement accuracy depends on the accuracy of numerous models, including the VLBI station position. Intensives observed with the Maunakea (Mk) and Pie Town (Pt) stations of the Very Long Baseline Array (VLBA) illustrate how a geologic event (i.e., the Mw 6.9 Hawai‘i Earthquake of May 4th, 2018) can cause a station displacement and an associated offset in the values of UT1−UTC measured by that baseline, rendering the data from the series useless until it is corrected. Using the nonparametric Nadaraya–Watson estimator to smooth the measured UT1−UTC values before and after the earthquake, we calculate the offset in the measurement to be 75.7 ± 4.6 μs. Analysis of the sensitivity of the Mk-Pt baseline’s UT1−UTC measurement to station position changes shows that the measured offset is consistent with the 67.2 ± 5.9 μs expected offset based on the 12.4 ± 0.6 mm total coseismic displacement of the Maunakea VLBA station determined from the displacement of the co-located global navigation satellite system (GNSS) station. GNSS station position information is known with a latency on the order of tens of hours and thus can be used to correct the a priori position model of a co-located VLBI station such that it can continue to provide accurate measurements of the critical EOP UT1−UTC as part of Intensive sessions. In the absence of a co-located GNSS receiver, the VLBI station position model would likely not be updated for several months, and a near real-time correction would not be possible. This contrast highlights the benefit of co-located GNSS and VLBI stations in support of the monitoring of UT1−UTC with single-baseline Intensives.Numéro de notice : A2023-133 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-022-01690-1 Date de publication en ligne : 03/03/2023 En ligne : https://doi.org/10.1007/s00190-022-01690-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102678
in Journal of geodesy > vol 97 n° 3 (March 2023) . - n° 21[article]BDS-3 precise orbit and clock solution at Wuhan University: status and improvement / Jing Guo in Journal of geodesy, vol 97 n° 2 (February 2023)
PermalinkCoastal GNSS-R phase altimetry based on the combination of L1 and L5 signals under high sea states / Yunqiao He in Journal of geodesy, vol 97 n° 2 (February 2023)
PermalinkUndifferenced and uncombined GNSS time and frequency transfer with integer ambiguity resolution / Xiaolong Mi in Journal of geodesy, vol 97 n° 2 (February 2023)
PermalinkAn extended inter-system biases model for multi-GNSS precise point positioning / Xuexi Liu in Measurement, vol 206 (January 2023)
PermalinkAutonomous coordinate establishment of local reference frames for ground-based positioning systems without known points / Tengfei Wang in Journal of geodesy, vol 97 n° 1 (January 2023)
PermalinkBDS and GPS side-lobe observation quality analysis and orbit determination with a GEO satellite onboard receiver / Wenwen Li in GPS solutions, vol 27 n° 1 (January 2023)
PermalinkChildren’s walking to urban services: an analysis of pedestrian access to social infrastructures and its relationship with land use / Wonjun No in International journal of geographical information science IJGIS, vol 37 n° 1 (January 2023)
PermalinkComparative use of PPK-integrated close-range terrestrial photogrammetry and a handheld mobile laser scanner in the measurement of forest road surface deformation / Remzi Eker in Measurement, vol 206 (January 2023)
PermalinkEstablishing a high-precision real-time ZTD model of China with GPS and ERA5 historical data and its application in PPP / Pengfei Xia in GPS solutions, vol 27 n° 1 (January 2023)
PermalinkGENESIS: co-location of geodetic techniques in space / Pacôme Delva in Earth, Planets and Space, vol 75 n° 1 (2023)
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