Centre dedocumentation
scientifique

Adaptive regularization method for 3-D GNSS ionospheric tomography based on the U-curve / Jun Tang in IEEE Transactions on geoscience and remote sensing, vol 59 n° 6 (June 2021)  

Public [article]  inIEEE Transactions on geoscience and remote sensing > vol 59 n° 6 (June 2021) . - pp 4547 - 4560 Titre : Adaptive regularization method for 3-D GNSS ionospheric tomography based on the U-curve Type de document : Article/Communication Auteurs : Jun Tang, Auteur ; Xin Gao, Auteur Année de publication : 2021 Article en page(s) : pp 4547 - 4560 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] données GNSS [Termes IGN] modèle ionosphérique [Termes IGN] problème inverse [Termes IGN] teneur totale en électrons [Termes IGN] tomographie par GPS Résumé : (auteur) Computerized ionospheric tomography is a highly ill-posed inverse problem, and regularization tends to stabilize the problem to provide a unique solution. When a regularization method is used, the choice of an optimal parameter is a key issue. In this article, we propose an adaptive regularization method for 3-D ionospheric tomography based on the U-curve. The proposed approach uses a U-curve method to determine the optimal regularization parameter from Global Navigation Satellite Systems (GNSS) observation data. Comparative case studies are investigated based on GNSS simulated observations and real measurements. The simulation results indicate that the proposed method is superior to the adaptive regularization method based on the L-curve. In addition, we further validate the tomographic results with actual ionosonde station data. The results demonstrate the reliability and superiority of the proposed method compared to traditional methods. Numéro de notice : A2021-422 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3022561 date de publication en ligne : 22/09/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3022561 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97777 [article]

GNSS-based statistical analysis of ionospheric anomalies during typhoon landings in Taiwan/Japan / Hai Peng in IEEE Transactions on geoscience and remote sensing, vol 59 n° 6 (June 2021)  

Public [article]  inIEEE Transactions on geoscience and remote sensing > vol 59 n° 6 (June 2021) . - pp 5272 - 5279 Titre : GNSS-based statistical analysis of ionospheric anomalies during typhoon landings in Taiwan/Japan Type de document : Article/Communication Auteurs : Hai Peng, Auteur ; Yibin Yao, Auteur ; Jian Kong, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 5272 - 5279 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] cyclone [Termes IGN] données GNSS [Termes IGN] onde de gravité [Termes IGN] perturbation ionosphérique [Termes IGN] phase [Termes IGN] propagation ionosphérique [Termes IGN] signal GNSS [Termes IGN] Taïwan [Termes IGN] teneur totale en électrons [Termes IGN] vitesse Résumé : (auteur) Using the Global Navigation Satellite System (GNSS) differenced total electron content (dTEC) series, the traveling ionosphere disturbances (TIDs) of 22 typhoons registered in Taiwan/Japan between 2013 and 2016 were studied. The horizontal speed of the first TID during a typhoon landing can be estimated by a two-station method with the ionosphere anomaly indicator in total electron count units (TECUs) (|dTEC| ≥ 0.15 TECU). The horizontal speed of the TIDs was from 155 to 210 m/s and with an average speed of 168.70 m/s. The estimated TID speeds of Typhoons Soudelor (205.93 m/s) and Megi (158.47 m/s) are not consistent with each other, even though they had very similar trajectories when cross through Taiwan Island. Moreover, the propagation velocity of the typhoon ionospheric anomaly showed a significant positive correlation ( r=0.78 , α=0.05 ) with the change rate of the typhoon central air pressure and a negative correlation ( r=−0.52 , α=0.05 ) with the central pressure before landing. Gravity waves were generated by land friction, terrain blocking, and strong wind shear transport energy into the atmosphere from the near surface to the mesosphere and thermosphere, which is the main cause of ionosphere disturbances during typhoon landing. Numéro de notice : A2021-428 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3004829 date de publication en ligne : 24/08/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3004829 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97784 [article]

Le RGF93v2b : une nouvelle réalisation du RGF93 / Romain Fagès in XYZ, n° 167 (juin 2021)

Public [article]  inXYZ > n° 167 (juin 2021) . - pp 26-29 Titre : Le RGF93v2b : une nouvelle réalisation du RGF93 Type de document : Article/Communication Auteurs : Romain Fagès, Auteur Année de publication : 2021 Article en page(s) : pp 26-29 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux [Termes IGN] données GNSS [Termes IGN] géodésie spatiale [Termes IGN] International Terrestrial Reference Frame [Termes IGN] maintenance [Termes IGN] mise à jour [Termes IGN] réseau géodésique français 1993 Résumé : (Auteur) Le 4 janvier 2021, l’IGN a effectué une opération de maintenance du repère de référence géodésique RGF93 en publiant une nouvelle réalisation de celui-ci, le RGF93v2b Numéro de notice : A2021-460 Affiliation des auteurs : IGN (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtSansCL DOI : sans date de publication en ligne : 01/06/2021 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97883 [article]

An improved computerized ionospheric tomography model fusing 3-D multisource ionospheric data enabled quantifying the evolution of magnetic storm / Jian Kong in IEEE Transactions on geoscience and remote sensing, vol 59 n° 5 (May 2021)  

Public [article]  inIEEE Transactions on geoscience and remote sensing > vol 59 n° 5 (May 2021) . - pp 3725 - 3736 Titre : An improved computerized ionospheric tomography model fusing 3-D multisource ionospheric data enabled quantifying the evolution of magnetic storm Type de document : Article/Communication Auteurs : Jian Kong, Auteur ; Lulu Shan, Auteur ; Chen Zhou, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 3725 - 3736 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] données GNSS [Termes IGN] erreur absolue [Termes IGN] filtre de Kalman [Termes IGN] fusion de données multisource [Termes IGN] modèle ionosphérique [Termes IGN] modèle stochastique [Termes IGN] perturbation ionosphérique [Termes IGN] tempête magnétique [Termes IGN] teneur totale en électrons [Termes IGN] tomographie Résumé : (auteur) Global Navigation Satellite System (GNSS) ionospheric tomography is a typical ill-posed problem. Joint inversion with external observation data is one of the effective ways to mitigate the problem. In this article, by fusing 3-D multisource ionospheric data, and improving the stochastic model, an improved GNSS tomographic algorithm MFCIT [computerized ionospheric tomography (CIT) using mapping function] is presented. The accuracy of the algorithm is validated by selected data under different geomagnetic and solar conditions acquired in Europe. The results show that the estimated, statistically significant uncertainty for each of the layers is about 0.50–3.0TECU, with the largest absolute error within 6.0TECU. The advantage of the MFCIT is that it is based on the Kalman filter, which enables efficient near real-time 3-D monitoring of ionosphere. The temporal resolution can reach ~1 min level. Here, we apply the ionospheric tomography inversion to the magnetic storm on January 7, 2015, in the European region, and quantified the evolution of the storm. The results show that the difference of the core region between the MFCIT and CODE GIM is less than 1TECU. More importantly, during the initial phase of the storm, when the ionospheric disturbance is not evident in the single layer CODE GIM model, the MFCIT shows obvious positive disturbances in the upper ionosphere, although there is no disturbance in the F2 layer. The MFCIT further tracks the evolution of the magnetic storm that the ionospheric disturbance expands from the upper to the lower ionosphere layers, and at UT12:00, the disturbance continues to spread to the F2 layer. Numéro de notice : A2021-396 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3022949 date de publication en ligne : 24/09/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3022949 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97686 [article]

Impact of observation sampling rate on multi-GNSS static PPP performance / Berkay Bahadur in Survey review, Vol 53 n° 378 (May 2021)  

Public [article]  inSurvey review > Vol 53 n° 378 (May 2021) . - pp 206 - 215 Titre : Impact of observation sampling rate on multi-GNSS static PPP performance Type de document : Article/Communication Auteurs : Berkay Bahadur, Auteur ; Metin Nohutcu, Auteur Année de publication : 2021 Article en page(s) : pp 206 - 215 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] données GLONASS [Termes IGN] données GNSS [Termes IGN] données GPS [Termes IGN] positionnement ponctuel précis [Termes IGN] positionnement statique [Termes IGN] taux d'échantillonnage [Termes IGN] temps de convergence [Vedettes matières IGN] Traitement de données GNSS Résumé : (auteur) The main objective of this study is to investigate the impact of observation sampling rate on the PPP performance, in terms of positioning accuracy and convergence time, under different multi-GNSS combinations. For this purpose, daily observation datasets collected at ten IGS-MGEX (International GNSS Service-Multi-GNSS Experiment) stations during the 1-week period of January 6-12, 2019 with 1-s, 5-s,15-s, and 30-s sampling rates were processed under three different PPP processing modes, namely GPS-only, GPS/GLONASS and multi-GNSS. The results indicate that the use of high-rate observation sampling improves the PPP performance for all processing modes significantly. The contribution of increasing sampling rate, both for positioning error and convergence time, is more prominent in shorter periods, especially within the first 30 min for all processing modes. Finally, the multi-GNSS processing mode with the 1-s observation sampling rate has the best PPP performance and offers a considerable prospect for the GNSS applications. Numéro de notice : A2021-403 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2019.1711346 date de publication en ligne : 12/01/2020 En ligne : https://doi.org/10.1080/00396265.2019.1711346 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97716 [article]

Integrated water vapour observations in the Caribbean arc from a network of ground-based GNSS receivers during EUREC4A / Olivier Bock in Earth System Science Data, vol 13 n° 5 (May 2021)  

Permalink

Understanding collective human movement dynamics during large-scale events using big geosocial data analytics / Junchuan Fan in Computers, Environment and Urban Systems, vol 87 (May 2021)  

Permalink

Integer phase clock method with single-satellite ambiguity fixing and its application in LEO satellite orbit determination / Kai Shao in Acta Geodaetica et Cartographica Sinica, vol 50 n° 4 ([20/04/2021])  

Permalink

1996–2017 GPS position time series, velocities and quality measures for the CORS Network / Jarir Saleh in Journal of applied geodesy, vol 15 n° 2 (April 2021)  

Permalink

EUREC4A / Bjorn Stevens in Earth System Science Data, vol 13 n° 4 (April 2021)  

Permalink

Impact of the third frequency GNSS pseudorange and carrier phase observations on rapid PPP convergences / Jiang Guo in GPS solutions, vol 25 n° 2 (April 2021)  

Permalink

POD of small LEO satellites based on precise real-time MADOCA and SBAS-aided PPP corrections / Amir Allahvirdi-Zadeh in GPS solutions, vol 25 n° 2 (April 2021)  

Permalink

Precipitable water vapor fusion based on a generalized regression neural network / Bao Zhang in Journal of geodesy, vol 95 n° 4 (April 2021)  

Permalink

The Realization and evaluation of PPP ambiguity resolution with INS aiding in marine survey / Zhenqiang Du in Marine geodesy, vol 44 n° 2 (March 2021)  

Permalink

Modélisation des délais ionosphériques appliquée au traitement PPP-RTK centimétrique avec ambiguïtés entières de phase / Camille Parra in XYZ, n° 166 (mars 2021)

Permalink