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GNSS threat quantification in the United Kingdom in 2015 / Chaz Dixon in Navigation aérienne, maritime, spatiale, terrestre, vol 63 n° 250 (mai - août 2016)
[article]
Titre : GNSS threat quantification in the United Kingdom in 2015 Titre original : Quantification des menaces sur le GNSS au Royaume Uni en 2015 Type de document : Article/Communication Auteurs : Chaz Dixon, Auteur ; Steve Hill, Auteur ; Alper Ucar, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 52 - 64 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] brouillage
[Termes IGN] récepteur GNSS
[Termes IGN] signal GNSS
[Termes IGN] traitement du signalRésumé : (Auteur) Cet article, extrait du magazine COORDINATES présente un aperçu du système GEMNet ainsi que deux jeux de résultats. Tout d'abord, il s'agit des caractéristiques des signaux interférents, observés et enregistrés sur le terrain, et de leur impact potentiel sur deux types de récepteurs opérationnels. Ensuite il s'agit de résultats obtenus en laboratoire par le re-jeu des signatures de brouillage précédents, à un niveau significativement plus important, sur deux types de récepteurs. Numéro de notice : A2016-667 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81898
in Navigation aérienne, maritime, spatiale, terrestre > vol 63 n° 250 (mai - août 2016) . - pp 52 - 64[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 094-2016021 RAB Revue Centre de documentation En réserve L003 Disponible Review and critical analysis of mass and moments of inertia of the LAGEOS and LAGEOS II satellites for the LARASE program / Massimo Visco in Advances in space research, vol 57 n° 9 (May 2016)
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Titre : Review and critical analysis of mass and moments of inertia of the LAGEOS and LAGEOS II satellites for the LARASE program Type de document : Article/Communication Auteurs : Massimo Visco, Auteur ; David M. Lucchesi, Auteur Année de publication : 2016 Article en page(s) : pp 1928 – 1938 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Lageos
[Termes IGN] moment d'inertie
[Termes IGN] satellite de télémétrieRésumé : (auteur) The two LAGEOS satellites, currently the best tracked satellites by the stations of the International Laser Ranging Service (ILRS), play a significant role in the fields of space geodesy and geophysics as well as in very precise measurements and constraints in fundamental physics. Specifically, for the measurements of tiny relativistic effects it is mandatory to build accurate models for the dynamics of the satellites, in particular concerning their spin evolution and the determination of their temperature distribution and thermal behavior under different physical conditions. Consequently, an accurate knowledge of both the external and internal structure of the laser-ranged satellites, and of their main dynamic parameters to be used within the orbit models, is of crucial importance. In this work we reconstruct information about the structure, the materials used, and the moments of inertia of the two LAGEOS satellites. The moments of inertia of LAGEOS resulted to be 11.42±0.0311.42±0.03 kg m2 for the cylindrical symmetry axis and 10.96±0.0310.96±0.03 kg m2 for the other two main axes. The analogous quantities for LAGEOS II are 11.45±0.0311.45±0.03 kg m2 and 11.00±0.0311.00±0.03 kg m2. We also built a 3D-CAD model of the satellites structure which is useful for finite element-based analysis. We tried to solve contradictions and overcome several misunderstanding present in the historical literature of the older LAGEOS, carefully reanalyzing the earlier technical papers. To test the results we obtained, we used our moments of inertia to compute the spin evolution of the two satellites obtaining a good agreement between measured and estimated values for the spin direction and the rotational period. We believe we now have accurate knowledge of the mass, moments of inertia, and composition of both LAGEOS satellites. Numéro de notice : A2016-272 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2016.02.006 En ligne : http://dx.doi.org/10.1016/j.asr.2016.02.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80807
in Advances in space research > vol 57 n° 9 (May 2016) . - pp 1928 – 1938[article]CODE’s new ultra-rapid orbit and ERP products for the IGS / Simon Lutz in GPS solutions, vol 20 n° 2 (April 2016)
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Titre : CODE’s new ultra-rapid orbit and ERP products for the IGS Type de document : Article/Communication Auteurs : Simon Lutz, Auteur ; Gerhard Beutler, Auteur ; Stefan Schaer, Auteur ; Rolf Dach, Auteur ; Adrian Jäggi, Auteur Année de publication : 2016 Article en page(s) : pp 239 - 250 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Bernese
[Termes IGN] international GPS service for geodynamics
[Termes IGN] orbite
[Termes IGN] rotation de la TerreRésumé : (Auteur) The International GNSS Service (IGS) issues four sets of so-called ultra-rapid products per day, which are based on the contributions of the IGS Analysis Centers. The traditional (“old”) ultra-rapid orbit and earth rotation parameters (ERP) solution of the Center for Orbit Determination in Europe (CODE) was based on the output of three consecutive 3-day long-arc rapid solutions. Information from the IERS Bulletin A was required to generate the predicted part of the old CODE ultra-rapid product. The current (“new”) product, activated in November 2013, is based on the output of exactly one multi-day solution. A priori information from the IERS Bulletin A is no longer required for generating and predicting the orbits and ERPs. This article discusses the transition from the old to the new CODE ultra-rapid orbit and ERP products and the associated improvement in reliability and performance. All solutions used in this article were generated with the development version of the Bernese GNSS Software. The package was slightly extended to meet the needs of the new CODE ultra-rapid generation. Numéro de notice : A2016-613 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0432-2 En ligne : http://dx.doi.org/10.1007/s10291-014-0432-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81813
in GPS solutions > vol 20 n° 2 (April 2016) . - pp 239 - 250[article]GLONASS fractional-cycle bias estimation across inhomogeneous receivers for PPP ambiguity resolution / Jianghui Geng in Journal of geodesy, vol 90 n° 4 (April 2016)
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Titre : GLONASS fractional-cycle bias estimation across inhomogeneous receivers for PPP ambiguity resolution Type de document : Article/Communication Auteurs : Jianghui Geng, Auteur ; Yehuda Bock, Auteur Année de publication : 2016 Article en page(s) : pp 379 - 396 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] positionnement par GLONASS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïtéRésumé : (auteur) The key issue to enable precise point positioning with ambiguity resolution (PPP-AR) is to estimate fractional-cycle biases (FCBs), which mainly relate to receiver and satellite hardware biases, over a network of reference stations. While this has been well achieved for GPS, FCB estimation for GLONASS is difficult because (1) satellites do not share the same frequencies as a result of Frequency Division Multiple Access (FDMA) signals; (2) and even worse, pseudorange hardware biases of receivers vary in an irregular manner with manufacturers, antennas, domes, firmware, etc., which especially complicates GLONASS PPP-AR over inhomogeneous receivers. We propose a general approach where external ionosphere products are introduced into GLONASS PPP to estimate precise FCBs that are less impaired by pseudorange hardware biases of diverse receivers to enable PPP-AR. One month of GLONASS data at about 550 European stations were processed. From an exemplary network of 51 inhomogeneous receivers, including four receiver types with various antennas and spanning about 800 km in both longitudinal and latitudinal directions, we found that 92.4 % of all fractional parts of GLONASS wide-lane ambiguities agree well within ±0.15 cycles with a standard deviation of 0.09 cycles if global ionosphere maps (GIMs) are introduced, compared to only 51.7 % within ±0.15 cycles and a larger standard deviation of 0.22 cycles otherwise. Hourly static GLONASS PPP-AR at 40 test stations can reach position estimates of about 1 and 2 cm in RMS from ground truth for the horizontal and vertical components, respectively, which is comparable to hourly GPS PPP-AR. Integrated GLONASS and GPS PPP-AR can further achieve an RMS of about 0.5 cm in horizontal and 1–2 cm in vertical components. We stress that the performance of GLONASS PPP-AR across inhomogeneous receivers depends on the accuracy of ionosphere products. GIMs have a modest accuracy of only 2–8 TECU (Total Electron Content Unit) in vertical which confines PPP-AR to an approximately 800×800 km area in Europe. We expect that a regional ionosphere map with a better than 1 TECU accuracy is likely to improve the GLONASS PPP-AR efficiency. Numéro de notice : A2016-251 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0879-0 Date de publication en ligne : 26/12/2015 En ligne : https://doi.org/10.1007/s00190-015-0879-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80759
in Journal of geodesy > vol 90 n° 4 (April 2016) . - pp 379 - 396[article]Performance analysis of triple-frequency ambiguity resolution with BeiDou observations / Xiaohong Zhang in GPS solutions, vol 20 n° 2 (April 2016)
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Titre : Performance analysis of triple-frequency ambiguity resolution with BeiDou observations Type de document : Article/Communication Auteurs : Xiaohong Zhang, Auteur ; Xiyang He, Auteur Année de publication : 2016 Article en page(s) : pp 269 - 281 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] compensation Lambda
[Termes IGN] correction du trajet multiple
[Termes IGN] données BeiDou
[Termes IGN] performance
[Termes IGN] récepteur trifréquence
[Termes IGN] résolution d'ambiguïtéRésumé : (Auteur) We investigate triple-frequency ambiguity resolution performance using real BeiDou data. We test four ambiguity resolution (AR) methods which are applicable to triple-frequency observations. These are least squares ambiguity decorrelation adjustment (LAMBDA), GF-TCAR (geometry-free three-carrier ambiguity resolution), GB-TCAR (geometry-based three-carrier ambiguity resolution) and GIF-TCAR (three-carrier ambiguity resolution based on the geometry-free and ionospheric-free combination). A comparison between LAMBDA, GF-TCAR and GB-TCAR was conducted over three short baselines and two medium baselines. The results indicated that LAMBDA is optimal in both short baseline and medium baseline cases. However, the performances of GB-TCAR and LAMBDA differ slightly for short baselines. Compared with GF-TCAR, which uses the geometry-free model, the GB-TCAR using the geometry-based model improves the AR performance significantly. Compared with dual-frequency observations, the LAMBDA AR results show a significant improvement when using triple-frequency observations over short baselines. The performance of GIF-TCAR is evaluated using multi-epoch observations. The results indicated that multi-path errors on carrier phases will have a significant influence on GIF-TCAR AR results, which leads to different GIF-TCAR AR performance for different type of satellites. For GEO (Geostationary Orbit) satellites, the ambiguities can barely be correctly fixed because the multi-path errors on carrier phases are very systematic. For IGSO (Inclined Geosynchronous Orbit) and MEO (Medium Earth Orbit) satellites, when the elevation cutoff angle is set as 30°, several tens to several hundreds of epochs are needed for correctly fixing the narrow lane ambiguities. The comparison of positioning performance between dual-frequency observations and triple-frequency observations was also conducted. The results indicated that a minor improvement can be achieved by using triple-frequency observations compared with using dual-frequency observations. Numéro de notice : A2016-614 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0434-0 En ligne : http://dx.doi.org/10.1007/s10291-014-0434-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81814
in GPS solutions > vol 20 n° 2 (April 2016) . - pp 269 - 281[article]Combined Architecture : Enhancing Multi-Dimensional Signal Quality in GNSS Receivers / Nunzia Giorgia Ferrara in Inside GNSS, vol 11 n° 2 (March - April 2016)PermalinkGNSS & the Law: GLONASS and PNT in Russia / Alexey Bolkunov in Inside GNSS, vol 11 n° 2 (March - April 2016)PermalinkMIDAS robust trend estimator for accurate GPS station velocities without step detection / Geoffrey Blewitt in Journal of geophysical research : Solid Earth, vol 121 n° 3 (March 2016)PermalinkIonospheric corrections for single-frequency tracking of GNSS satellites by VLBI based on co-located GNSS / Benjamin Männel in Journal of geodesy, vol 90 n° 2 (February 2016)PermalinkPermalinkDetermination of terrestrial frames by optimal combination of GNSS, DORIS and SLR measurements / Myriam Zoulida (2016)PermalinkDPOD2008, A DORIS-oriented terrestrial reference frame for precise orbit determination / Pascal Willis (2016)PermalinkGAGAN - India’s SBAS : Redefining Navigation over the Indian Region / A.S. Ganeshan in Inside GNSS, vol 11 n° 1 (January - February 2016)PermalinkGalileo Turns Twelve / Anonyme in GPS world, vol 27 n° 1 (January 2016)PermalinkGNSS Satellite-Based Augmentation Systems : A potential new time keeping system for future generations / Carlo Cornacchini in Inside GNSS, vol 11 n° 1 (January - February 2016)Permalink