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An extended inter-system biases model for multi-GNSS precise point positioning / Xuexi Liu in Measurement, vol 206 (January 2023)
[article]
Titre : An extended inter-system biases model for multi-GNSS precise point positioning Type de document : Article/Communication Auteurs : Xuexi Liu, Auteur ; Weiping Jiang, Auteur ; Pan Li, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 112306 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] distorsion du signal
[Termes IGN] échelle de temps
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] modèle mathématique
[Termes IGN] positionnement par BeiDou
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision du positionnementRésumé : (auteur) The inter-system bias (ISB) is an important parameter in multi-GNSS precise point positioning (PPP). However, on the one hand, the generation mechanism and error components of ISB are not clear. On the other hand, it is unclear whether the ISB parameter should be added to the BDS-2/BDS-3 combined PPP. First, in order to solve these problems, an extended ISB mathematical model is proposed, which unifies the common errors between receiver and satellite, and extends the original ISB model. Second, to demonstrate the correctness of the new model, the components of the new ISB model are verified, and then it is used to explain whether the ISB parameter should be added to BDS-2/BDS-3 combined PPP. Furthermore, 41 stations from the MGEX network and precise products from COD (Center for Orbit Determination in Europe), GBM (Deutsches GeoForschungsZentrum) and WUM (Wuhan University) are used to calculate and analyze the multi-GNSS PPP and ISB during day of year (DOY) 307–365, 2020. Finally, we propose to use a different estimation method of ISB with different precise products to improve the positioning accuracy and shorten the convergence time. The experimental results show that: (1) ISB parameter is composed of five parts: time system error, receiver hardware delay, signal distortion biases (SDB), MGEX-realized (multi-GNSS experiment) time scale and other unmodeled deviations. (2) Due to different receiver hardware delay, SDB and MGEX-realized time scale between BDS-2 and BDS-3, it is necessary to add an ISB parameter in BDS-2/BDS-3 PPP. (3) In multi-GNSS PPP, if the ISB changes greatly but the traditional constant method is used to estimate the ISB parameter, the impact on single station PPP coordinates can reach decimeters. The statistical results demonstrate that the RMS of GBM(CON(Constant)) in East (E), North (N) and Up (U) directions are 2.34 cm, 0.60 cm, and 1.59 cm, respectively, while the RMS of GBM(RWK(Random walk)) decreased by 59.8 %, 13.3 %, and 18.2 %, respectively. Numéro de notice : A2023-028 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.measurement.2022.112306 Date de publication en ligne : 06/12/2022 En ligne : https://doi.org/10.1016/j.measurement.2022.112306 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102269
in Measurement > vol 206 (January 2023) . - n° 112306[article]Création d’un graphe de connaissances géohistorique à partir d’annuaires du commerce parisien du 19ème siècle : application aux métiers de la photographie / Solenn Tual (2023)
Titre : Création d’un graphe de connaissances géohistorique à partir d’annuaires du commerce parisien du 19ème siècle : application aux métiers de la photographie Type de document : Article/Communication Auteurs : Solenn Tual , Auteur ; Nathalie Abadie , Auteur ; Bertrand Duménieu , Auteur ; Joseph Chazalon, Auteur ; Edwin Carlinet, Auteur Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2023 Projets : SODUCO / Perret, Julien Conférence : IC 2023, 34es journées francophones d'Ingénierie des connaissances 03/07/2023 05/07/2023 Strasbourg France Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] bruit (théorie du signal)
[Termes IGN] entité géographique
[Termes IGN] réseau sémantique
[Termes IGN] visualisation 4DIndex. décimale : 37.20 Analyse spatiale et ses outils Résumé : (auteur) Les annuaires professionnels anciens, édités à un rythme soutenu dans de nombreuses villes européennes tout au long des XIXe et XXe siècles, forment un corpus de sources unique par son volume et la possibilité qu'ils donnent de suivre les transformations urbaines à travers le prisme des activités professionnelles des habitants, de l'échelle individuelle jusqu'à celle de la ville entière. L'analyse spatiotemporelle d'un type de commerces au travers des entrées d'annuaires demande cependant un travail considérable de recensement, de transcription et de recoupement manuels. Pour pallier cette difficulté, cet article propose une approche automatique pour construire et visualiser un graphe de connaissances géohistorique des commerces figurant dans des annuaires anciens. L'approche est testée sur des annuaires du commerce parisien du XIXe siècle allant de 1799 à 1908, sur le cas des métiers de la photographie. Numéro de notice : C2023-012 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://hal.science/hal-04121643 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103319 Establishing 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)
[article]
Titre : Establishing a high-precision real-time ZTD model of China with GPS and ERA5 historical data and its application in PPP Type de document : Article/Communication Auteurs : Pengfei Xia, Auteur ; Mengxiang Tong, Auteur ; Shirong Ye, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 2 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Chine
[Termes IGN] correction troposphérique
[Termes IGN] données météorologiques
[Termes IGN] grille
[Termes IGN] positionnement ponctuel précis
[Termes IGN] retard troposphérique zénithal
[Termes IGN] série de Fourier
[Termes IGN] série temporelle
[Termes IGN] station GNSS
[Termes IGN] temps de convergence
[Termes IGN] temps réel
[Termes IGN] variation diurneRésumé : (auteur) A high-precision real-time troposphere model is constructed by combining ground-based GNSS observation data and the latest European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (ERA5). First, the zenith tropospheric delay (ZTD) is extracted in real time with high accuracy by combining the data of more than 500 GNSS stations in the Crustal Movement Observation Network of China (CMONOC) and national reference station network (NRSN); second, a grid model of the elevation normalization model (ENM) in China using ERA5 data is constructed, which takes into account the annual, semiannual and daily cycles. The ZTD estimated by GNSS stations at different heights based on precise point positioning (PPP) is normalized to a uniform height based on ENM; in addition, the optimal smoothing factors of the Gauss distance weighting function in different seasons are determined based on ERA5, which contributes to improved accuracy of ZTD interpolated from GNSS-derived ZTD to ZTD at grid points; finally, a real-time 1° × 1°ZTD grid model of China is created; the broadcast interval is extended to 6 min from few seconds. The new ZTD model has been evaluated using the data of 15 GNSS stations in China in 2020. The test results show that the new ZTD model deviates from the reference value with a mean value better than − 0.09 cm and RMSE, better than 1.44 cm compared with the ZTD estimated by post-processing GNSS, while the mean value of the deviation is -0.13 cm, and the RMSE is approximately 3.11 cm compared with radiosonde-derived ZTD. The new ZTD grid model can be used to enhance GNSS/PPP. Two weeks of GNSS observations, one week in winter and another in summer, were randomly collected for PPP processing. The statistical results show the convergence time in the vertical directions is shortened by 37.4% and 38.6% at the 95% and 68% confidence levels after ZTD constraints are applied to the float PPP solution, respectively. Numéro de notice : A2023-004 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-022-01338-9 Date de publication en ligne : 07/10/2022 En ligne : https://doi.org/10.1007/s10291-022-01338-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101874
in GPS solutions > vol 27 n° 1 (January 2023) . - n° 2[article]INS-assisted inter-system biases estimation and inter-system ambiguity resolution in a complex environment / Wenhao Zhao in GPS solutions, vol 27 n° 1 (January 2023)
[article]
Titre : INS-assisted inter-system biases estimation and inter-system ambiguity resolution in a complex environment Type de document : Article/Communication Auteurs : Wenhao Zhao, Auteur ; Genyou Liu, Auteur ; Ming Gao, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 3 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] centrale inertielle
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] filtre de Kalman
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] résolution d'ambiguïté
[Termes IGN] système complexe
[Termes IGN] trajet multipleRésumé : (auteur) The inter-system real-time kinematic (RTK) model in which multiple systems choose the same reference satellite uses more observations than the traditional intra-system RTK model; however, it is still difficult to accurately determine the differential inter-system biases (DISB) and inter-system ambiguity in a complex environment. We propose a tightly coupled inter-system RTK/INS model that uses the high-precision position information the inertial navigation system (INS) provides to assist in DISB estimation and inter-system ambiguity resolution. Vehicle experiments on urban roads were designed to verify the effectiveness of the method. The vehicle experiments consisted of a simulated rare satellite environment with a high cutoff elevation angle and a real complex environment with buildings and trees obscuration. A robust Kalman filter strategy is used to combat the effects of multipath and non-line-of-sight signals in real complex environments. The results indicate that with the help of INS, the standard deviation of phase and code DISB is reduced by 11 and 17%, respectively, in the simulated environment and by 33 and 18%, respectively, in the real complex environment. Compared with the intra-system RTK/INS model, inter-system RTK/INS mode 3D positioning root-mean-square error is reduced by 79% in the simulated environment and by 27% in the real complex environment. In the single-epoch mode, the ambiguity success rates of the inter-system RTK/INS model, inter-system RTK model, intra-system RTK/INS model and intra-system RTK model are 89, 74, 69 and 58%, respectively, in the simulated environment, and 68, 41, 64 and 12%, respectively, in the real complex environment. Numéro de notice : A2023-003 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-022-01347-8 Date de publication en ligne : 09/10/2022 En ligne : https://doi.org/10.1007/s10291-022-01347-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101873
in GPS solutions > vol 27 n° 1 (January 2023) . - n° 3[article]Multipath mitigation for improving GPS narrow-lane uncalibrated phase delay estimation and speeding up PPP ambiguity resolution / Kai Zheng in Measurement, vol 206 (January 2023)
[article]
Titre : Multipath mitigation for improving GPS narrow-lane uncalibrated phase delay estimation and speeding up PPP ambiguity resolution Type de document : Article/Communication Auteurs : Kai Zheng, Auteur ; Lingmin Tan, Auteur ; Kezhong Liu, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 112243 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse en composantes principales
[Termes IGN] atténuation
[Termes IGN] correction du trajet multiple
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] phase GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Termes IGN] temps de convergence
[Termes IGN] trajet multipleRésumé : (auteur) Precise point positioning (PPP) has been recognized as a powerful tool for various geophysical applications. However, the long convergence time required to resolve a reliable ambiguity impedes its further application in time-critical scenarios. Although PPP ambiguity resolution (AR) can shorten the convergence time, its performance is subject to the quality of float ambiguity estimates and the uncalibrated phase delay (UPD), which can be contaminated by multipath errors. Furthermore, the observation residuals derived from PPP are very likely to be affected by the common-mode error (CME), thereby deteriorating the multipath modeling accuracy. The principal component analysis (PCA) is employed to mitigate the CME effect, and the multipath is modeled using a multipath hemispherical map (MHM). Consequently, the narrow-lane (NL) UPDs with multipath correction have better temporal stability and residual distributions than those without correction. Compared with sidereal filtering (SF), the MHM0.5 has comparable residual variance reduction percentages, indicating its capability of capturing high-frequency multipath. For static PPP AR, the averaged time to first fix (TTFF) can be reduced by 24.2% to about 26 min and the convergence time can be achieved within 16.2 min after multipath correction. The pseudorange multipath correction significantly contributes to shortening the TTFF and convergence time. Reducing the resolution of MHM increases the risk of extending the TTFF. For kinematic PPP AR with MHM0.5, the convergence time exhibits a remarkable improvement when compared with that of the uncorrected case (21.7 min versus 40.2 min), and 20% of the stations achieve convergence within 10 min. Meanwhile, a few stations only take one minute to achieve convergence. The contribution of the multipath correction to the fixing rate is comparatively small. After applying MHM0.5, the kinematic positioning accuracies are improved by 35.7%, 12.6%, and 24.4% to 1.26, 1.39, and 2.73 cm for the east, north, and up components, respectively. Numéro de notice : A2023-027 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.measurement.2022.112243 Date de publication en ligne : 24/11/2022 En ligne : https://doi.org/10.1016/j.measurement.2022.112243 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102267
in Measurement > vol 206 (January 2023) . - n° 112243[article]Semi-supervised label propagation for multi-source remote sensing image change detection / Fan Hao in Computers & geosciences, vol 170 (January 2023)PermalinkPermalinkTree position estimation from TLS data using hough transform and robust least-squares circle fitting / Maja Michałowska in Remote Sensing Applications: Society and Environment, RSASE, vol 29 (January 2023)PermalinkWavelet-like denoising of GNSS data through machine learning. Application to the time series of the Campi Flegrei volcanic area (Southern Italy) / Rolando Carbonari in Geomatics, Natural Hazards and Risk, vol 14 n° 1 (2023)PermalinkConsistency assessment of multi-date PlanetScope imagery for seagrass percent cover mapping in different seagrass meadows / Pramaditya Wicaksono in Geocarto international, vol 37 n° 27 ([20/12/2022])PermalinkBathymetry and benthic habitat mapping in shallow waters from Sentinel-2A imagery: A case study in Xisha islands, China / Wei Huang in IEEE Transactions on geoscience and remote sensing, vol 60 n° 12 (December 2022)PermalinkHigh-precision positioning using plane-constrained RTK method in urban environments / Chen Zhuang in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)PermalinkMulti-frequency simulation of ionospheric scintillation using a phase-screen model / Fernando D. Nunes in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)PermalinkNavigation and Ionosphere Characterization Using High-Frequency Signals: A Performance Analysis / Yoav Baumgarten in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)PermalinkRobust modeling of GNSS orbit and clock error dynamics / Elisa Gallon in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)Permalink