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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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Fast ambiguity resolution for long-range reference station networks with ionospheric model constraint method / Ming Zhang in GPS solutions, vol 21 n° 2 (April 2017)
[article]
Titre : Fast ambiguity resolution for long-range reference station networks with ionospheric model constraint method Type de document : Article/Communication Auteurs : Ming Zhang, Auteur ; Hui Liu, Auteur ; Zhengdong Bai, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 617 – 626 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GNSS
[Termes IGN] erreur
[Termes IGN] modèle ionosphérique
[Termes IGN] résolution d'ambiguïté
[Termes IGN] retard ionosphèrique
[Termes IGN] station de référenceRésumé : (auteur) Ambiguity resolution (AR) speed is one of the most important performance indicators of a network RTK (real-time kinematics) system. Given the low correlation between the error sources of two stations, the effect of the atmospheric delay of double-difference observations cannot be ignored, thus making it difficult to fix the ambiguities. Ionospheric delay is one of the largest error sources affecting AR. This error source is reduced by the ionospheric-free combination with traditional methods. The AR speed of these methods is slow; generally, tens of minutes and even more are required for initialization. This study proposes an ionospheric model constraint (IMC) method to improve the AR speed. External information is not required apart from observations. The double-difference ionospheric delay is described with a regional double-difference ionospheric model, the coefficients of which are estimated as parameters together with ambiguities and tropospheric delays. Experimental results show that the initialization speed significantly improves by 72.5 % and that the AR speed for the newly risen satellites increases by 84.3 % with the proposed IMC method. Furthermore, the percentage of correctly fixed integer ambiguities after initialization increases to some extent. Numéro de notice : A2017-215 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0551-z En ligne : http://dx.doi.org/10.1007/s10291-016-0551-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85087
in GPS solutions > vol 21 n° 2 (April 2017) . - pp 617 – 626[article]Global ionosphere maps based on GNSS, satellite altimetry, radio occultation and DORIS / Peng Chen in GPS solutions, vol 21 n° 2 (April 2017)
[article]
Titre : Global ionosphere maps based on GNSS, satellite altimetry, radio occultation and DORIS Type de document : Article/Communication Auteurs : Peng Chen, Auteur ; Yi Bin Yao, Auteur ; Wanqiang Yao, Auteur Année de publication : 2017 Article en page(s) : pp 639 – 650 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] coordonnées GNSS
[Termes IGN] données altimétriques
[Termes IGN] données DORIS
[Termes IGN] ionosphère
[Termes IGN] modèle ionosphérique
[Termes IGN] occultation du signal
[Termes IGN] radiooccultation
[Termes IGN] teneur verticale totale en électronsRésumé : (auteur) Global ionosphere maps (GIMs) provided by the global navigation satellite systems (GNSS) data are essential in ionospheric research as the source of the global vertical total electron content (VTEC). However, conventional GIMs experience lower accuracy and reliability from uneven distribution of GNSS tracking stations, especially in ocean areas with few tracking stations. The orbits of ocean altimetry satellite cover vast ocean areas and can directly provide VTEC at nadir with two different wavelengths of radio waves. Radio occultation observations and the beacons of Doppler orbitography and radio positioning integrated by satellite (DORIS) are evenly distributed globally. Satellite altimetry, radio occultation and DORIS can compensate GNSS data in ocean areas, allowing a more accurate and reliable GIMs to be formed with the integration of these observations. This study builds GIMs with temporal intervals of 2 h by the integration of GNSS, satellite altimetry, radio occultation and DORIS data. We investigate the integration method for multi-source data and used the data in May 2013 to validate the effectiveness of integration. Result shows that VTEC changes by −11.0 to −7.0 TECU after the integration of satellite altimetry, radio occultation and DORIS data. The maximum root mean square decreases by 5.5 TECU, and the accuracy of GIMs in ocean areas improves significantly. Numéro de notice : A2017-216 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0554-9 En ligne : http://dx.doi.org/10.1007/s10291-016-0554-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85089
in GPS solutions > vol 21 n° 2 (April 2017) . - pp 639 – 650[article]Ionospheric error contribution to GNSS single-frequency navigation at the 2014 solar maximum / Raul Orus Perez in Journal of geodesy, vol 91 n° 4 (April 2017)
[article]
Titre : Ionospheric error contribution to GNSS single-frequency navigation at the 2014 solar maximum Type de document : Article/Communication Auteurs : Raul Orus Perez, Auteur Année de publication : 2017 Article en page(s) : pp 397 - 407 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] correction ionosphérique
[Termes IGN] éruption solaire
[Termes IGN] International GNSS Service
[Termes IGN] International Reference Ionosphere
[Termes IGN] modèle ionosphérique
[Termes IGN] récepteur bifréquence
[Termes IGN] récepteur monofréquence
[Termes IGN] retard ionosphèrique
[Termes IGN] signal Galileo
[Termes IGN] signal GPS
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) For single-frequency users of the global satellite navigation system (GNSS), one of the main error contributors is the ionospheric delay, which impacts the received signals. As is well-known, GPS and Galileo transmit global models to correct the ionospheric delay, while the international GNSS service (IGS) computes precise post-process global ionospheric maps (GIM) that are considered reference ionospheres. Moreover, accurate ionospheric maps have been recently introduced, which allow for the fast convergence of the real-time precise point position (PPP) globally. Therefore, testing of the ionospheric models is a key issue for code-based single-frequency users, which constitute the main user segment. Therefore, the testing proposed in this paper is straightforward and uses the PPP modeling applied to single- and dual-frequency code observations worldwide for 2014. The usage of PPP modeling allows us to quantify—for dual-frequency users—the degradation of the navigation solutions caused by noise and multipath with respect to the different ionospheric modeling solutions, and allows us, in turn, to obtain an independent assessment of the ionospheric models. Compared to the dual-frequency solutions, the GPS and Galileo ionospheric models present worse global performance, with horizontal root mean square (RMS) differences of 1.04 and 0.49 m and vertical RMS differences of 0.83 and 0.40 m, respectively. While very precise global ionospheric models can improve the dual-frequency solution globally, resulting in a horizontal RMS difference of 0.60 m and a vertical RMS difference of 0.74 m, they exhibit a strong dependence on the geographical location and ionospheric activity. Numéro de notice : A2017-106 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0971-0 En ligne : http://dx.doi.org/10.1007/s00190-016-0971-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84496
in Journal of geodesy > vol 91 n° 4 (April 2017) . - pp 397 - 407[article]Ionospheric tomography using GNSS: multiplicative algebraic reconstruction technique applied to the area of Brazil / Fabricio Dos Santos Prol in GPS solutions, vol 20 n° 4 (October 2016)
[article]
Titre : Ionospheric tomography using GNSS: multiplicative algebraic reconstruction technique applied to the area of Brazil Type de document : Article/Communication Auteurs : Fabricio Dos Santos Prol, Auteur ; Paulo de Oliveira Camargo, Auteur Année de publication : 2016 Article en page(s) : pp 807 - 814 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Brésil
[Termes IGN] code GNSS
[Termes IGN] International Reference Ionosphere
[Termes IGN] modèle ionosphérique
[Termes IGN] phase GNSS
[Termes IGN] récepteur GNSS
[Termes IGN] teneur totale en électrons
[Termes IGN] tomographie par GPSRésumé : (Auteur) Experimental analysis was performed using multiplicative algebraic reconstruction technique (MART) to map the ionosphere over Brazil. Code and phase observations from the global navigation satellite system (GNSS) together with the international reference ionosphere (IRI) enabled the estimation of ionospheric profiles and total electron content (TEC) over the entire region. Twenty-four days of data collected from existing ground-based GNSS receivers during the recent solar maximum period were used to analyze the performance of the MART algorithm. The results were compared with four ionosondes. It was demonstrated that MART estimated the electron density peak with the same degree of accuracy as the IRI model in regions with appropriate geometrical coverage by GNSS receivers for tomographic reconstruction. In addition, the slant TEC, as estimated with MART, presented lower root-mean-square error than the TEC calculated by ionospheric maps available from the International GNSS Service (IGS). Furthermore, the daily variations of the ionosphere were better represented with the algebraic techniques, compared to the IRI model and IGS maps, enabling a correlation of the elevation of the ionosphere at higher altitudes with the equatorial ionization anomaly intensification. The tomographic representations also enabled the detection of high vertical gradients at the same instants in which ionospheric irregularities were evident. Numéro de notice : A2016--030 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0490-0 En ligne : http://dx.doi.org/10.1007/s10291-015-0490-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83932
in GPS solutions > vol 20 n° 4 (October 2016) . - pp 807 - 814[article]Single-frequency precise point positioning using multi-constellation GNSS: GPS, Glonass, Galileo and Beidou / Mahmoud Abd Rabbou in Geomatica, vol 70 n° 2 (June 2016)
[article]
Titre : Single-frequency precise point positioning using multi-constellation GNSS: GPS, Glonass, Galileo and Beidou Type de document : Article/Communication Auteurs : Mahmoud Abd Rabbou, Auteur ; Ahmed El-Rabbany, Auteur Année de publication : 2016 Article en page(s) : pp 113 - 122 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] constellation GNSS
[Termes IGN] modèle ionosphérique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précisRésumé : (auteur) Single-frequency precise point positioning (PPP) presents a cost-effective positioning technique for a large number of users. However, it possesses low positioning accuracy and convergence time compared with the dual-frequency PPP. Single-frequency PPP commonly employs GPS satellite systems that suffer from poor satellite geometry, especially in dense urban areas. We develop a new single-frequency PPP model that combines the observations of current GNSS constellations, including GPS, GLONASS, Galileo and Beidou. The MGEX IGS final precise products are utilized to account for the orbital and clock errors, while the IGS final global ionospheric maps (GIM) model is used to correct for the ionospheric delay. The GNSS inter-system biases are treated as additional unknowns in the estimation process. The contribution of the additional GNSS observations to single-frequency PPP is assessed through solution comparison with its traditional GPS-only counterpart. Various GNSS combinations are considered in the assessment, including GPS/GLONASS, GPS/Galileo, GPS/BeiDou and all-constellation GNSS. It is shown that the additional GNSS observations enhance the PPP solution accuracy and convergence time in comparison with the traditional GPS-only solution. Except for stations with a sufficient number of tracked BeiDou satellites, both Galileo and BeiDou have marginal effects on the positioning accuracy due to their limited number of satellites. However, for stations with a sufficient number of visible BeiDou satellites, an average of 40% PPP accuracy improvement is obtained. The major contribution to the PPP accuracy enhancement is obtained from GLONASS satellite observations. Numéro de notice : A2016-679 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.5623/cig2016-203 En ligne : http://dx.doi.org/10.5623/cig2016-203 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81933
in Geomatica > vol 70 n° 2 (June 2016) . - pp 113 - 122[article]Reconstruction of the vertical electron density profile based on vertical TEC using the simulated annealing algorithm / Chunhua Jiang in Advances in space research, vol 57 n° 10 (May 2016)PermalinkAccuracy of ionospheric models used in GNSS and SBAS: methodology and analysis / Adria Rovira-Garcia in Journal of geodesy, vol 90 n° 3 (March 2016)PermalinkWide-area ionospheric delay model for GNSS users in middle- and low-magnetic-latitude regions / An-Lin Tao in GPS solutions, vol 20 n° 1 (January 2016)PermalinkA worldwide ionospheric model for fast precise point positioning / Adria Rovira-Garcia in IEEE Transactions on geoscience and remote sensing, vol 53 n° 8 (August 2015)PermalinkIonospheric effects in uncalibrated phase delay estimation and ambiguity-fixed PPP based on raw observable model / Shengfeng Gu in Journal of geodesy, vol 89 n° 5 (May 2015)PermalinkAn alternative ionospheric correction model for global navigation satellite systems / M.M. Hoque in Journal of geodesy, vol 89 n° 4 (April 2015)PermalinkRegional 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)PermalinkSHPTS: 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)PermalinkEstimating ionospheric delay using GPS/Galileo signals in the E5 band / Olivier Julien in Inside GNSS, vol 10 n° 2 (March - April 2015)PermalinkAssessing and mitigating the effects of the ionospheric variability on DGPS / Duojie Weng in GPS solutions, vol 19 n° 1 (January 2015)PermalinkReducing 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)Permalinkvol 85 n° 12 - December 2011 - Special issue : Ionosphere (Bulletin de Journal of geodesy) / M. SchmidtPermalinkThe 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)Permalink