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Ionospheric correction using NTCM driven by GPS Klobuchar coefficients for GNSS applications / M.M. Hoque in GPS solutions, vol 21 n° 4 (October 2017)
[article]
Titre : Ionospheric correction using NTCM driven by GPS Klobuchar coefficients for GNSS applications Type de document : Article/Communication Auteurs : M.M. Hoque, Auteur ; N. Jakowski, Auteur ; J. Berdermann, Auteur Année de publication : 2017 Article en page(s) : pp 1563 - 1572 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] atténuation du signal
[Termes IGN] correction ionosphérique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] récepteur monofréquence
[Termes IGN] teneur totale en électronsRésumé : (Auteur) Global Navigation Satellite Systems (GNSS) require mitigation of ionospheric propagation errors because the ionospheric range errors might be larger than tens of meters at the zenith direction. Taking advantage of the frequency-dispersive property of ionospheric refractivity, the ionospheric range errors can be mitigated in dual-frequency applications to a great extent by a linear combination of carrier phases or pseudoranges. However, single-frequency GNSS operations require additional ionospheric information to apply signal delay or range error corrections. To aid single-frequency operations, the global positioning system (GPS) broadcasts 8 coefficients as part of the navigation message to drive the ionospheric correction algorithm (ICA) also known as Klobuchar model. We presented here an ionospheric correction algorithm called Neustrelitz TEC model (NTCM) which can be used as complementary to the GPS ICA. Our investigation shows that the NTCM can be driven by Klobuchar model parameters to achieve a significantly better performance than obtained by the mother ICA algorithm. Our research, using post-processed reference total electron content (TEC) data from more than one solar cycle, shows that on average the RMS modeled TEC errors are up to 40% less for the proposed NTCM model compared to the Klobuchar model during high solar activity period, and about 10% less during low solar activity period. Such an approach does not require major technology changes for GPS users rather requires only introducing the NTCM approach a complement to the existing ICA algorithm while maintaining the simplicity of ionospheric range error mitigation with an improved model performance. Numéro de notice : A2017-616 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-017-0632-7 En ligne : https://doi.org/10.1007/s10291-017-0632-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86926
in GPS solutions > vol 21 n° 4 (October 2017) . - pp 1563 - 1572[article]Real-time multi-GNSS single-frequency precise point positioning / Peter F. de Bakker in GPS solutions, vol 21 n° 4 (October 2017)
[article]
Titre : Real-time multi-GNSS single-frequency precise point positioning Type de document : Article/Communication Auteurs : Peter F. de Bakker, Auteur ; Christian C. J. M. Tiberius, Auteur Année de publication : 2017 Article en page(s) : pp 1791 - 1803 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] récepteur monofréquence
[Termes IGN] temps réel
[Termes IGN] test de performanceRésumé : (Auteur) Precise Point Positioning (PPP) is a popular Global Positioning System (GPS) processing strategy, thanks to its high precision without requiring additional GPS infrastructure. Single-Frequency PPP (SF-PPP) takes this one step further by no longer relying on expensive dual-frequency GPS receivers, while maintaining a relatively high positioning accuracy. The use of GPS-only SF-PPP for lane identification and mapping on a motorway has previously been demonstrated successfully. However, the performance was shown to depend strongly on the number of available satellites, limiting the application of SF-PPP to relatively open areas. We investigate whether the applicability can be extended by moving from using only GPS to using multiple Global Navigation Satellite Systems (GNSS). Next to GPS, the Russian GLONASS system is at present the only fully functional GNSS and was selected for this reason. We introduce our approach to multi-GNSS SF-PPP and demonstrate its performance by means of several experiments. Results show that multi-GNSS SF-PPP indeed outperforms GPS-only SF-PPP in particular in case of reduced sky visibility. Numéro de notice : A2017-618 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-017-0653-2 En ligne : https://doi.org/10.1007/s10291-017-0653-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86928
in GPS solutions > vol 21 n° 4 (October 2017) . - pp 1791 - 1803[article]Application of the undifferenced GNSS precise positioning in determining coordinates in national reference frames / Grzegorz Krzan in Artificial satellites, vol 52 n° 3 (September 2017)
[article]
Titre : Application of the undifferenced GNSS precise positioning in determining coordinates in national reference frames Type de document : Article/Communication Auteurs : Grzegorz Krzan, Auteur ; Katarzyna Stępniak, Auteur Année de publication : 2017 Article en page(s) : pp 49 - 69 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] coordonnées géodésiques
[Termes IGN] Napeos
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision centimétrique
[Termes IGN] récepteur bifréquence
[Termes IGN] récepteur GPS
[Termes IGN] réseau permanent EUREF
[Termes IGN] système de référence géodésique
[Termes IGN] système de référence localRésumé : (Auteur) In high-accuracy positioning using GNSS, the most common solution is still relative positioning using double-difference observations of dual-frequency measurements. An increasingly popular alternative to relative positioning are undifferenced approaches, which are designed to make full use of modern satellite systems and signals. Positions referenced to global International Terrestrial Reference Frame (ITRF2008) obtained from Precise Point Positioning (PPP) or Undifferenced (UD) network solutions have to be transformed to national (regional) reference frame, which introduces additional bases related to the transformation process. In this paper, satellite observations from two test networks using different observation time series were processed. The first test concerns the positioning accuracy from processing one year of dual-frequency GPS observations from 14 EUREF Permanent Network (EPN) stations using NAPEOS 3.3.1 software. The results were transformed into a national reference frame (PL-ETRF2000) and compared to positions from an EPN cumulative solution, which was adopted as the true coordinates. Daily observations were processed using PPP and UD multi-station solutions to determine the final accuracy resulting from satellite positioning, the transformation to national coordinate systems and Eurasian intraplate plate velocities. The second numerical test involved similar processing strategies of post-processing carried out using different observation time series (30 min., 1 hour, 2 hours, daily) and different classes of GNSS receivers. The centimeter accuracy of results presented in the national coordinate system satisfies the requirements of many surveying and engineering applications. Numéro de notice : A2017-594 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/arsa-2017-0006 En ligne : https://doi.org/10.1515/arsa-2017-0006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86802
in Artificial satellites > vol 52 n° 3 (September 2017) . - pp 49 - 69[article]Determination of the ionospheric foF2 using a stand-alone GPS receiver / Dudy D Wijaya in Journal of geodesy, vol 91 n° 9 (September 2017)
[article]
Titre : Determination of the ionospheric foF2 using a stand-alone GPS receiver Type de document : Article/Communication Auteurs : Dudy D Wijaya, Auteur ; Haris Haralambous, Auteur ; Christina Oikonomou, Auteur ; Wedyanto Kuntjoro, Auteur Année de publication : 2017 Article en page(s) : pp 1117 – 1133 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] filtre de Kalman
[Termes IGN] gradient ionosphèrique
[Termes IGN] International Reference Ionosphere
[Termes IGN] ionosphère
[Termes IGN] récepteur GPS
[Termes IGN] sonde spatiale
[Termes IGN] teneur totale en électronsRésumé : (auteur) The critical frequency of ionospheric F2 layer (foF2) is a measure of the highest frequency of radio signal that may be reflected back by the F2 layer, and it is associated with ionospheric peak electron density in the F2 layer. Accurate long-term foF2 variations are usually derived from ionosonde observations. In this paper, we propose a new method to observe foF2 using a stand-alone global positioning system (GPS) receiver. The proposed method relies on the mathematical equation that relates foF2 to GPS observations. The equation is then implemented in the Kalman filter algorithm to estimate foF2 at every epoch of the observation (30-s rate). Unlike existing methods, the proposed method does not require any additional information from ionosonde observations and does not require any network of GPS receivers. It only requires as inputs the ionospheric scale height and the modeled plasmaspheric electron content, which practically can be derived from any existing ionospheric/plasmaspheric model. We applied the proposed method to estimate long-term variations of foF2 at three GPS stations located at the northern hemisphere (NICO, Cyprus), the southern hemisphere (STR1, Australia) and the south pole (SYOG, Antarctic). To assess the performance of the proposed method, we then compared the results against those derived by ionosonde observations and the International Reference Ionosphere (IRI) 2012 model. We found that, during the period of high solar activity (2011–2012), the values of absolute mean bias between foF2 derived by the proposed method and ionosonde observations are in the range of 0.2–0.5 MHz, while those during the period of low solar activity (2009–2010) are in the range of 0.05–0.15 MHz. Furthermore, the root-mean-square-error (RMSE) values during high and low solar activities are in the range of 0.8–0.9 MHz and of 0.6–0.7 MHz, respectively. We also noticed that the values of absolute mean bias and RMSE between foF2 derived by the proposed method and the IRI-2012 model are slightly larger than those between the proposed method and ionosonde observations. These results demonstrate that the proposed method can estimate foF2 with a comparable accuracy. Since the proposed method can estimate foF2 at every epoch of the observation, it therefore has promising applications for investigating various scales (from small to large) of foF2 irregularities. Numéro de notice : A2017-481 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-017-1013-2 En ligne : https://doi.org/10.1007/s00190-017-1013-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86412
in Journal of geodesy > vol 91 n° 9 (September 2017) . - pp 1117 – 1133[article]Group delay variations of GPS transmitting and receiving antennas / Lambert Wanninger in Journal of geodesy, vol 91 n° 9 (September 2017)
[article]
Titre : Group delay variations of GPS transmitting and receiving antennas Type de document : Article/Communication Auteurs : Lambert Wanninger, Auteur ; Hael Sumaya, Auteur ; Susanne Beer, Auteur Année de publication : 2017 Article en page(s) : pp 1099 – 1116 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] code GPS
[Termes IGN] constellation GPS
[Termes IGN] erreur
[Termes IGN] ionosphère
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] phase GPS
[Termes IGN] récepteur bifréquence
[Termes IGN] récepteur GPS
[Termes IGN] signal GPS
[Termes IGN] teneur totale en électronsRésumé : (auteur) GPS code pseudorange measurements exhibit group delay variations at the transmitting and the receiving antenna. We calibrated C1 and P2 delay variations with respect to dual-frequency carrier phase observations and obtained nadir-dependent corrections for 32 satellites of the GPS constellation in early 2015 as well as elevation-dependent corrections for 13 receiving antenna models. The combined delay variations reach up to 1.0 m (3.3 ns) in the ionosphere-free linear combination for specific pairs of satellite and receiving antennas. Applying these corrections to the code measurements improves code/carrier single-frequency precise point positioning, ambiguity fixing based on the Melbourne–Wübbena linear combination, and determination of ionospheric total electron content. It also affects fractional cycle biases and differential code biases. Numéro de notice : A2017-480 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-017-1012-3 En ligne : https://doi.org/10.1007/s00190-017-1012-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86411
in Journal of geodesy > vol 91 n° 9 (September 2017) . - pp 1099 – 1116[article]Performance evaluation of single-frequency point positioning with GPS, GLONASS, BeiDou and Galileo / L. Pan in Survey review, vol 49 n° 354 (September 2017)PermalinkImpact of GPS differential code bias in dual- and triple-frequency positioning and satellite clock estimation / Haojun Li in GPS solutions, vol 21 n° 3 (July 2017)PermalinkReview of code and phase biases in multi-GNSS positioning / Martin Håkansson in GPS solutions, vol 21 n° 3 (July 2017)PermalinkLightweight UAV with on-board photogrammetry and single-frequency GPS positioning for metrology applications / Mehdi Daakir in ISPRS Journal of photogrammetry and remote sensing, vol 127 (May 2017)PermalinkIonospheric 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)PermalinkRapid initialization of real-time PPP by resolving undifferenced GPS and GLONASS ambiguities simultaneously / Jianghui Geng in Journal of geodesy, vol 91 n° 4 (April 2017)PermalinkEstimation and analysis of Galileo differential code biases / Min Li in Journal of geodesy, vol 91 n° 3 (March 2017)PermalinkPermalinkSurveillance de santé structurale des ouvrages d’art incluant les systèmes de positionnement par satellites / Camille Favre in XYZ, n° 150 (mars - mai 2017)PermalinkDouble take : mitigating interference with a dual-polarized antenna array in a real environment / Matteo Sgammini in GPS world, vol 28 n° 2 (February 2017)Permalink