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Termes IGN > sciences naturelles > sciences de la Terre et de l'univers > géosciences > géographie physique > météorologie > aérologie > atmosphère terrestre > ionosphère > modèle ionosphérique
modèle ionosphériqueSynonyme(s)modèle de propagation ionosphèrique |
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An alternative ionospheric correction model for global navigation satellite systems / M.M. Hoque in Journal of geodesy, vol 89 n° 4 (April 2015)
[article]
Titre : An alternative ionospheric correction model for global navigation satellite systems Type de document : Article/Communication Auteurs : M.M. Hoque, Auteur ; Norbert Jakowski, Auteur Année de publication : 2015 Article en page(s) : pp 391 - 406 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] correction ionosphérique
[Termes IGN] ionosphère
[Termes IGN] modèle ionosphérique
[Termes IGN] propagation ionosphériqueRésumé : (auteur) The ionosphere is recognized as a major error source for single-frequency operations of global navigation satellite systems (GNSS). To enhance single-frequency operations the global positioning system (GPS) uses an ionospheric correction algorithm (ICA) driven by 8 coefficients broadcasted in the navigation message every 24 h. Similarly, the global navigation satellite system Galileo uses the electron density NeQuick model for ionospheric correction. The Galileo satellite vehicles (SVs) transmit 3 ionospheric correction coefficients as driver parameters of the NeQuick model. In the present work, we propose an alternative ionospheric correction algorithm called Neustrelitz TEC broadcast model NTCM-BC that is also applicable for global satellite navigation systems. Like the GPS ICA or Galileo NeQuick, the NTCM-BC can be optimized on a daily basis by utilizing GNSS data obtained at the previous day at monitor stations. To drive the NTCM-BC, 9 ionospheric correction coefficients need to be uploaded to the SVs for broadcasting in the navigation message. Our investigation using GPS data of about 200 worldwide ground stations shows that the 24-h-ahead prediction performance of the NTCM-BC is better than the GPS ICA and comparable to the Galileo NeQuick model. We have found that the 95 percentiles of the prediction error are about 16.1, 16.1 and 13.4 TECU for the GPS ICA, Galileo NeQuick and NTCM-BC, respectively, during a selected quiet ionospheric period, whereas the corresponding numbers are found about 40.5, 28.2 and 26.5 TECU during a selected geomagnetic perturbed period. However, in terms of complexity the NTCM-BC is easier to handle than the Galileo NeQuick and in this respect comparable to the GPS ICA. Numéro de notice : A2015-344 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0783-z Date de publication en ligne : 13/12/2014 En ligne : https://doi.org/10.1007/s00190-014-0783-z Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76716
in Journal of geodesy > vol 89 n° 4 (April 2015) . - pp 391 - 406[article]Regional vertical total electron content (VTEC) modeling together with satellite and receiver differential code biases (DCBs) using semi-parametric multivariate adaptive regression B-splines (SP-BMARS) / Murat Durmaz in Journal of geodesy, vol 89 n° 4 (April 2015)
[article]
Titre : Regional vertical total electron content (VTEC) modeling together with satellite and receiver differential code biases (DCBs) using semi-parametric multivariate adaptive regression B-splines (SP-BMARS) Type de document : Article/Communication Auteurs : Murat Durmaz, Auteur ; Mahmut Onur Karslioglu, Auteur Année de publication : 2015 Article en page(s) : pp 347 - 360 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] B-Spline
[Termes IGN] erreur systématique
[Termes IGN] harmonique sphérique
[Termes IGN] modèle ionosphérique
[Termes IGN] régression multiple
[Termes IGN] teneur totale en électrons
[Termes IGN] teneur verticale totale en électronsRésumé : (auteur) There are various global and regional methods that have been proposed for the modeling of ionospheric vertical total electron content (VTEC). Global distribution of VTEC is usually modeled by spherical harmonic expansions, while tensor products of compactly supported univariate B-splines can be used for regional modeling. In these empirical parametric models, the coefficients of the basis functions as well as differential code biases (DCBs) of satellites and receivers can be treated as unknown parameters which can be estimated from geometry-free linear combinations of global positioning system observables. In this work we propose a new semi-parametric multivariate adaptive regression B-splines (SP-BMARS) method for the regional modeling of VTEC together with satellite and receiver DCBs, where the parametric part of the model is related to the DCBs as fixed parameters and the non-parametric part adaptively models the spatio-temporal distribution of VTEC. The latter is based on multivariate adaptive regression B-splines which is a non-parametric modeling technique making use of compactly supported B-spline basis functions that are generated from the observations automatically. This algorithm takes advantage of an adaptive scale-by-scale model building strategy that searches for best-fitting B-splines to the data at each scale. The VTEC maps generated from the proposed method are compared numerically and visually with the global ionosphere maps (GIMs) which are provided by the Center for Orbit Determination in Europe (CODE). The VTEC values from SP-BMARS and CODE GIMs are also compared with VTEC values obtained through calibration using local ionospheric model. The estimated satellite and receiver DCBs from the SP-BMARS model are compared with the CODE distributed DCBs. The results show that the SP-BMARS algorithm can be used to estimate satellite and receiver DCBs while adaptively and flexibly modeling the daily regional VTEC. Numéro de notice : A2015-342 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0779-8 Date de publication en ligne : 23/11/2014 En ligne : https://doi.org/10.1007/s00190-014-0779-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76712
in Journal of geodesy > vol 89 n° 4 (April 2015) . - pp 347 - 360[article]SHPTS: towards a new method for generating precise global ionospheric TEC map based on spherical harmonic and generalized trigonometric series functions / Zishen Li in Journal of geodesy, vol 89 n° 4 (April 2015)
[article]
Titre : SHPTS: towards a new method for generating precise global ionospheric TEC map based on spherical harmonic and generalized trigonometric series functions Type de document : Article/Communication Auteurs : Zishen Li, Auteur ; Yunbin Yuan, Auteur ; Ningbo Wang, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 333 - 345 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] données DORIS
[Termes IGN] données Topex-Poseidon
[Termes IGN] fonction harmonique
[Termes IGN] harmonique sphérique
[Termes IGN] modèle ionosphérique
[Termes IGN] série de Fourier
[Termes IGN] signal GNSS
[Termes IGN] teneur totale en électrons
[Termes IGN] trigonométrie sphériqueRésumé : (auteur) To take maximum advantage of the increasing Global Navigation Satellite Systems (GNSS) data to improve the accuracy and resolution of global ionospheric TEC map (GIM), an approach, named Spherical Harmonic plus generalized Trigonometric Series functions (SHPTS), is proposed by integrating the spherical harmonic and the generalized trigonometric series functions on global and local scales, respectively. The SHPTS-based GIM from January 1st, 2001 to December 31st, 2011 (about one solar cycle) is validated by the ionospheric TEC from raw global GPS data, the GIM released by the current Ionospheric Associate Analysis Center (IAAC), the TOPEX/Poseidon satellite and the DORIS. The present results show that the SHPTS-based GIM over the area where no real data are available has the same accuracy level (approximately 2–6 TECu) to that released by the current IAAC. However, the ionospheric TEC in the SHPTS-based GIM over the area covered by real data is more accurate (approximately 1.5 TECu) than that of the GIM (approximately 3.0 TECu) released by the current IAAC. The external accuracy of the SHPTS-based GIM validated by the TOPEX/Poseidon and DORIS is approximately 2.5–5.5 and 1.5–4.5 TECu, respectively. In particular, the SHPTS-based GIM is the best or almost the best ranked, along with those of JPL and UPC, when they are compared with TOPEX/Poseidon measurements, and the best (in addition to UPC) when they are validated with DORIS data. With the increase in the number of GNSS satellites and contributing stations, the performance of the SHPTS-based GIM can be further improved. The SHPTS-based GIM routinely calculated using global GPS, GLONASS and BDS data will be found at the website http://www.gipp.org.cn. Numéro de notice : A2015-341 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0778-9 Date de publication en ligne : 02/12/2014 En ligne : https://doi.org/10.1007/s00190-014-0778-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76710
in Journal of geodesy > vol 89 n° 4 (April 2015) . - pp 333 - 345[article]Estimating ionospheric delay using GPS/Galileo signals in the E5 band / Olivier Julien in Inside GNSS, vol 10 n° 2 (March - April 2015)
[article]
Titre : Estimating ionospheric delay using GPS/Galileo signals in the E5 band Type de document : Article/Communication Auteurs : Olivier Julien, Auteur ; Jean-Luc Issler, Auteur ; Laurent Lestarquit, Auteur ; Lionel Ries, Auteur Année de publication : 2015 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] modèle ionosphérique
[Termes IGN] retard ionosphèrique
[Termes IGN] signal Galileo
[Termes IGN] signal GPS
[Termes IGN] traitement du signalRésumé : (éditeur) Building on previous research efforts, the authors present a novel technique to improve ionospheric modeling using various configurations of GPS and Galileo signals in the E5 band. Numéro de notice : A2015-253 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.insidegnss.com/node/4435 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76293
in Inside GNSS > vol 10 n° 2 (March - April 2015)[article]Assessing and mitigating the effects of the ionospheric variability on DGPS / Duojie Weng in GPS solutions, vol 19 n° 1 (January 2015)
[article]
Titre : Assessing and mitigating the effects of the ionospheric variability on DGPS Type de document : Article/Communication Auteurs : Duojie Weng, Auteur ; Shengyue Ji, Auteur ; Wu Chen, Auteur ; Zhihua Li, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 107 - 116 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] GPS en mode différentiel
[Termes IGN] gradient ionosphèrique
[Termes IGN] ionosphère
[Termes IGN] modèle ionosphérique
[Termes IGN] retard ionosphèrique
[Termes IGN] traitement de données GNSSRésumé : (auteur) The differential GPS (DGPS) performance can be affected by the ionospheric variability, especially in low-latitude areas. We evaluated the behavior of the ionospheric variability in low-latitude areas in the 11-year cycle of the solar activity. During periods of solar maximum, the percentage of the daily maximum gradient that exceeds 50 mm/km has reached 73 % in 2001. Assuming that the baseline length is 20 km, the gradient larger than 50 mm/km can lead to more than 1.0-m ranging error, which is significant if we want to achieve meter-level accuracy with DGPS. An ionospheric gradient model built from a number of reference stations is proposed for estimating the differential ionospheric delays. The effectiveness of the model is demonstrated under both the quiet and active ionospheric conditions in low-latitude areas. For a short baseline length of 16.9 km in Hong Kong, the horizontal positioning accuracy can be improved by 41 and 61 % during active solar years and geomagnetic storms, respectively. The improvements show that the model is capable of reducing the spatial decorrelation caused by the ionospheric variability, and the model can be used in DGPS especially over the regions, such as low-latitude areas, where the large ionospheric variability happens frequently. Numéro de notice : A2015-201 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0372-x Date de publication en ligne : 13/04/2014 En ligne : https://doi.org/10.1007/s10291-014-0372-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76019
in GPS solutions > vol 19 n° 1 (January 2015) . - pp 107 - 116[article]Reducing distance dependent bias in low-cost single frequency GPS network to complement dual frequency GPS stations in order to derive detailed surface deformation field / H.-Y. Chen in Survey review, vol 47 n° 340 (January 2015)PermalinkGNSS ambiguity resolution with controllable failure rate for long baseline network RTK / Bofeng Li in Journal of geodesy, vol 88 n° 2 (February 2014)PermalinkIonospheric modeling using GPS: Greater fidelity using a 3D approach / Wei Zhang in GPS world, vol 25 n° 2 (February 2014)PermalinkPerformance evaluation of USTEC product for single-frequency precise point positioning / Mahmoud Abd-El-Rahman in Geomatica, vol 67 n° 4 (December 2013)PermalinkA technique for routinely updating the ITU-R database using radio occultation electron density profiles / Claudio Brunini in Journal of geodesy, vol 87 n° 9 (September 2013)PermalinkMéthodes de travail dans les réseaux GNSS, 3ème partie Méthodes du "statique multi-stations" / Romain Legros in XYZ, n° 134 (mars - mai 2013)PermalinkCombination of different space-geodetic observations for regional ionosphere modeling / D. Dettmering in Journal of geodesy, vol 85 n° 12 (December 2011)PermalinkThe international reference ionosphere today and in the future / Dieter Bilitza in Journal of geodesy, vol 85 n° 12 (December 2011)PermalinkThe ionosphere : effects, GPS modeling and the benefits for space geodetic techniques / Manuel Hernández-Pajares in Journal of geodesy, vol 85 n° 12 (December 2011)PermalinkValidation of international reference ionosphere models using in situ measurements from GRACE K-band ranging system and CHAMP planar Langmuir probe / C. Lee in Journal of geodesy, vol 85 n° 12 (December 2011)Permalink