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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]A fresh look at GNSS anti-jamming / Daniele Borio in Inside GNSS, vol 12 n° 5 (September - October 2017)
[article]
Titre : A fresh look at GNSS anti-jamming Type de document : Article/Communication Auteurs : Daniele Borio, Auteur ; Pau Closas, Auteur Année de publication : 2017 Article en page(s) : pp 54 - 61 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] anti-leurrage
[Termes IGN] brouillage
[Termes IGN] estimation de position
[Termes IGN] interférence
[Termes IGN] méthode robuste
[Termes IGN] mitigation
[Termes IGN] signal GNSSRésumé : (auteur) Although strong jamming can overwhelm much weaker GNSS signals, receiver performance can be significantly improved by implementing interference mitigation techniques. With this article we briefly discuss the most common approaches for interference mitigation and frame them with respect to the principles of Interference Cancellation (IC) and robust estimation. Additionally, we present initial results obtained using Robust Transform Domain (RTD) mitigation techniques. These techniques provide effective alternatives to Transform Domain excision, enabling receiver operations in the close proximity of a jammer. Numéro de notice : A2017-583 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.insidegnss.com/node/5618 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86718
in Inside GNSS > vol 12 n° 5 (September - October 2017) . - pp 54 - 61[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]Optimum stochastic modeling for GNSS tropospheric delay estimation in real-time / Tomasz Hadas in GPS solutions, vol 21 n° 3 (July 2017)
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Titre : Optimum stochastic modeling for GNSS tropospheric delay estimation in real-time Type de document : Article/Communication Auteurs : Tomasz Hadas, Auteur ; Felix Norman Teferle, Auteur ; Mathieu Kazmierski, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 1069 – 1081 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] données GNSS
[Termes IGN] optimisation spatiale
[Termes IGN] prévision météorologique
[Termes IGN] retard troposphérique
[Termes IGN] retard troposphérique zénithal
[Termes IGN] station GNSSRésumé : (auteur) In GNSS data processing, the station height, receiver clock and tropospheric delay (ZTD) are highly correlated to each other. Although the zenith hydrostatic delay of the troposphere can be provided with sufficient accuracy, zenith wet delay (ZWD) has to be estimated, which is usually done in a random walk process. Since ZWD temporal variation depends on the water vapor content in the atmosphere, it seems to be reasonable that ZWD constraints in GNSS processing should be geographically and/or time dependent. We propose to take benefit from numerical weather prediction models to define optimum random walk process noise. In the first approach, we used archived VMF1-G data to calculate a grid of yearly and monthly means of the difference of ZWD between two consecutive epochs divided by the root square of the time lapsed, which can be considered as a random walk process noise. Alternatively, we used the Global Forecast System model from National Centres for Environmental Prediction to calculate random walk process noise dynamically in real-time. We performed two representative experimental campaigns with 20 globally distributed International GNSS Service (IGS) stations and compared real-time ZTD estimates with the official ZTD product from the IGS. With both our approaches, we obtained an improvement of up to 10% in accuracy of the ZTD estimates compared to any uniformly fixed random walk process noise applied for all stations. Numéro de notice : A2017-443 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0595-0 En ligne : https://doi.org/10.1007/s10291-016-0595-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86365
in GPS solutions > vol 21 n° 3 (July 2017) . - pp 1069 – 1081[article]Review of code and phase biases in multi-GNSS positioning / Martin Håkansson in GPS solutions, vol 21 n° 3 (July 2017)
[article]
Titre : Review of code and phase biases in multi-GNSS positioning Type de document : Article/Communication Auteurs : Martin Håkansson, Auteur ; Anna B. O. Jensen, Auteur ; Milan Horemuz, Auteur ; Gunnar Hedling, Auteur Année de publication : 2017 Article en page(s) : pp 849 - 860 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] code GNSS
[Termes IGN] correction du signal
[Termes IGN] données GNSS
[Termes IGN] modèle ionosphérique
[Termes IGN] phase GNSS
[Termes IGN] positionnement par GNSS
[Termes IGN] précision du positionnement
[Termes IGN] récepteur GNSS
[Termes IGN] résolution d'ambiguïtéRésumé : (auteur) A review of the research conducted until present on the subject of Global Navigation Satellite System (GNSS) hardware-induced phase and code biases is here provided. Biases in GNSS positioning occur because of imperfections and/or physical limitations in the GNSS hardware. The biases are a result of small delays between events that ideally should be simultaneous in the transmission of the signal from a satellite or in the reception of the signal in a GNSS receiver. Consequently, these biases will also be present in the GNSS code and phase measurements and may there affect the accuracy of positions and other quantities derived from the observations. For instance, biases affect the ability to resolve the integer ambiguities in Precise Point Positioning (PPP), and in relative carrier phase positioning when measurements from multiple GNSSs are used. In addition, code biases affect ionospheric modeling when the Total Electron Content is estimated from GNSS measurements. The paper illustrates how satellite phase biases inhibit the resolution of the phase ambiguity to an integer in PPP, while receiver phase biases affect multi-GNSS positioning. It is also discussed how biases in the receiver channels affect relative GLONASS positioning with baselines of mixed receiver types. In addition, the importance of code biases between signals modulated onto different carriers as is required for modeling the ionosphere from GNSS measurements is discussed. The origin of biases is discussed along with their effect on GNSS positioning, and descriptions of how biases can be estimated or in other ways handled in the positioning process are provided. Numéro de notice : A2017-438 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0572-7 En ligne : https://doi.org/10.1007/s10291-016-0572-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86348
in GPS solutions > vol 21 n° 3 (July 2017) . - pp 849 - 860[article]Automatic GPS ionospheric amplitude and phase scintillation detectors using a machine learning algorithm / Yu Jiao in Inside GNSS, vol 12 n° 3 (May - June 2017)PermalinkCodeless code tracking of the Galileo E1 PRS / Cillian O'Driscoll in Inside GNSS, vol 12 n° 2 (March - April 2017)PermalinkReflected blessings : position estimation using non-line-of-sight GPS signals / Yuting Ng in GPS world, vol 28 n° 3 (March 2017)PermalinkInterference localization from space: part 2 applications / Luca Canzian in Inside GNSS, vol 12 n° 1 (January - February 2017)PermalinkOptimal Doppler-aided smoothing strategy for GNSS navigation / Zebo Zhou in GPS solutions, vol 21 n° 1 (January 2017)PermalinkA drift line bias estimator: ARMA-based filter or calibration method, and its application in BDS/GPS-based attitude determination / Zhang Liang in Journal of geodesy, vol 90 n° 12 (December 2016)PermalinkInterference localization from space: theoretical background / Luca Canzian in Inside GNSS, vol 11 n° 6 (November - December 2016)PermalinkSMAP L-Band microwave radiometer: RFI mitigation prelaunch analysis and first year on-orbit observations / Priscilla N. Mohammed in IEEE Transactions on geoscience and remote sensing, vol 54 n° 10 (October 2016)PermalinkGNSS interferometric radio occultation / Manuel Martín-Neira in IEEE Transactions on geoscience and remote sensing, vol 54 n° 9 (September 2016)PermalinkInterference mitigation in the E5A Galileo band using an open-source simulator / Diego Alonso in Inside GNSS, vol 11 n° 4 (July - August 2016)Permalink