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Generating distorded GNSS signals using a signal simulator / Mathieu Raimondi in GPS world, vol 24 n° 5 (May 2013)
[article]
Titre : Generating distorded GNSS signals using a signal simulator Type de document : Article/Communication Auteurs : Mathieu Raimondi, Auteur ; Eric Sénant, Auteur ; Charles Fernet, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 45 - 50 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] forme d'onde
[Termes IGN] positionnement par GNSS
[Termes IGN] signal Galileo
[Termes IGN] signal GPS
[Termes IGN] simulation de signalRésumé : (Auteur) INTEGRITY. It is one of the most desirable personality traits. It is the characteristic of truth and fair dealing, of honesty and sincerity. The word also can be applied to systems and actions with a meaning of soundness or being whole or undivided. This latter definition is clear when we consider that the word integrity comes from the Latin word integer, meaning untouched, intact, entire the same origin as that for the integers in mathematics: whole numbers without a fractional or decimal component. Integrity is perhaps the most important requirement of any navigation system (along with accuracy, availability, and continuity). It characterizes a system's ability to provide a timely warning when it fails to meet its stated accuracy. If it does not, we have an integrity failure and the possibility of conveying hazardously misleading information. GPS has built into it various checks and balances to ensure a fairly high level of integrity. However, GPS integrity failures have occasionally occurred. One of these was in 1990 when SVN19, a GPS Block II satellite operating as PRN19, suffered a hardware chain failure, which caused it to transmit an anomalous waveform, evidenced by carrier leakage on the L1 signal spectrum. Receivers continued to acquire and process the SVN19 signals, oblivious to the fact that the signal distortion resulted in position errors of three to eight meters. Errors of this magnitude would normally go unnoticed by most users, and the significance of the failure wasn't clear until March 1993 during some field tests of differential navigation for aided landings being conducted by the Federal Aviation Administration. The anomaly became known as the “evil waveform.”(I'm not sure who first came up with this moniker for the anomaly. Perhaps it was the folks at Stanford University who have worked closely with the FAA in its aircraft navigation research. The term has even made it into popular culture. The Japanese drone-metal rock band, Boris, released an album in 2005 titled Dronevil. One of the cuts on the album is “Evil Wave Form.” And if drone metal is not your cup of tea, you will find the title quite appropriate.). Other types of GPS evil waveforms are possible, and there is the potential for such waveforms to also occur in the signals of other global navigation satellite systems. It is important to fully understand the implications of these potential signal anomalies. In this month's column, our authors discuss a set of GPS and Galileo evil-waveform experiments they have carried out with an advanced GNSS RF signal simulator. Their results will help to benchmark the effects of distorted signals and perhaps lead to further improvements in GNSS signal integrity. Numéro de notice : A2013-250 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32388
in GPS world > vol 24 n° 5 (May 2013) . - pp 45 - 50[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 067-2013051 RAB Revue Centre de documentation En réserve L003 Disponible Stochastic modeling of high-stability ground clocks in GPS analysis / Kang Wang in Journal of geodesy, vol 87 n° 5 (May 2013)
[article]
Titre : Stochastic modeling of high-stability ground clocks in GPS analysis Type de document : Article/Communication Auteurs : Kang Wang, Auteur ; Markus Rothacher, Auteur Année de publication : 2013 Article en page(s) : pp 427 - 437 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] horloge atomique
[Termes IGN] modèle stochastique
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] propagation troposphérique
[Termes IGN] signal GPS
[Termes IGN] stabilité
[Termes IGN] temps atomique internationalRésumé : (Auteur) In current global positioning system (GPS) applications, receiver clocks are typically estimated epoch-wise in the data analyses even for clocks with high performance like Hydrogen-masers (H-maser). Applying an appropriate clock model for high-stability receiver clocks should, in view of the strong correlation between the station height and the clock parameters, significantly improve the positioning results. Recent experiments have shown that modeling the deterministic behavior of high-quality receiver clocks can improve the kinematic precise point positioning considerably. In this paper, well-behaving ground clocks are studied in detail applying constraints between subsequent and near-subsequent clock parameters. The influence of different weights for these relative clock constraints on the positioning quality, especially on the height, is investigated. For excellent clocks, an improvement of up to a factor of 3 can be obtained for the repeatability of the kinematic height estimates. This may be essential to detect small but sudden changes in the vertical component (e.g., caused by earthquakes). Troposphere zenith path delays (ZPD) are also heavily correlated with the receiver clock estimates and station heights. All these parameters are usually estimated simultaneously. We show that the use of relative clock constraints allows for a higher time resolution of the ZPD estimates (smaller than 2 h) without compromising the quality of the kinematic height estimates. Numéro de notice : A2013-253 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-013-0616-5 Date de publication en ligne : 19/03/2013 En ligne : https://doi.org/10.1007/s00190-013-0616-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32391
in Journal of geodesy > vol 87 n° 5 (May 2013) . - pp 427 - 437[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 266-2013051 SL Revue Centre de documentation Revues en salle Disponible Le positionnement par satellites et les maths / Jonathan Chenal in Tangente, n° 151 (mars-avril 2013)
[article]
Titre : Le positionnement par satellites et les maths Type de document : Article/Communication Auteurs : Jonathan Chenal , Auteur Année de publication : 2013 Article en page(s) : pp 16 - 17 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] éphémérides de satellite
[Termes IGN] horloge atomique
[Termes IGN] positionnement par GPS
[Termes IGN] signal GPSRésumé : (éditeur) Le positionnement par satellites, comme le GPS, repose en fait sur des mathématiques assez élémentaires. mais il faut tenir compte des sources d'erreurs qui perturbent les mesures (décalages d'horloges, ...). Alors comment fonctionnent les systèmes globaux de navigation par satellites ? Numéro de notice : A2013-834 Affiliation des auteurs : IGN (2012-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtSansCL DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=88263
in Tangente > n° 151 (mars-avril 2013) . - pp 16 - 17[article]Plans jet in motion for GPS: Receivers will operate in environments impossible today / B. Bruber in GPS world, vol 23 n° 12 (December 2012)
[article]
Titre : Plans jet in motion for GPS: Receivers will operate in environments impossible today Type de document : Article/Communication Auteurs : B. Bruber, Auteur Année de publication : 2012 Article en page(s) : pp 14 - 15 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] constellation GPS
[Termes IGN] récepteur GPS
[Termes IGN] secteur spatial
[Termes IGN] secteur terrien
[Termes IGN] signal GPS
[Termes IGN] utilisateurNuméro de notice : A2012-621 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32067
in GPS world > vol 23 n° 12 (December 2012) . - pp 14 - 15[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 067-2012121 RAB Revue Centre de documentation En réserve L003 Disponible Vector delay lock loops: How do vector delay lock loops predict the satellite signals? / M. Lashley in Inside GNSS, vol 7 n° 5 (September - October 2012)
[article]
Titre : Vector delay lock loops: How do vector delay lock loops predict the satellite signals? Type de document : Article/Communication Auteurs : M. Lashley, Auteur ; D. Bevly, Auteur Année de publication : 2012 Article en page(s) : pp 28 - 34 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] chronométrie
[Termes IGN] récepteur GPS
[Termes IGN] signal GPSRésumé : (Auteur) [extrait] GNSS receivers determine their position and clock bias by measuring the arrival times of satellite signals. Delay lock loops (DLLs) are used in traditional receivers to measure the arrival times of the signals. Numéro de notice : A2012-505 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31951
in Inside GNSS > vol 7 n° 5 (September - October 2012) . - pp 28 - 34[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 159-2012051 SL Revue Centre de documentation Revues en salle Disponible Documents numériques
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a2012-505_vector-delay-lock-loops.pdfAdobe Acrobat PDF Recent developments in Precise Point Positioning / Sunil Bisnath in Geomatica, vol 66 n° 2 (June 2012)PermalinkImpact of Earth radiation pressure on GPS position estimates / C. Rodriguez-Solano in Journal of geodesy, vol 86 n° 5 (May 2012)PermalinkSimulating GPS signals / A. Brown in GPS world, vol 23 n° 5 (May 2012)PermalinkPersonal privacy jammers: Locating Jersey PPDs jamming GBAS [Ground-Based Augmentation System] safety-of-life signals / J. Grabowski in GPS world, vol 23 n° 4 (April 2012)PermalinkGPS snow depth meter with geometry-free linear combinations of carrier phases / M. Ozeki in Journal of geodesy, vol 86 n° 3 (March 2012)PermalinkRay-traced slant factors for mitigating the tropospheric delay at the observation level / L. Urquhart in Journal of geodesy, vol 86 n° 2 (February 2012)PermalinkPermalinkThe ionosphere : effects, GPS modeling and the benefits for space geodetic techniques / Manuel Hernández-Pajares in Journal of geodesy, vol 85 n° 12 (December 2011)PermalinkInterpolating atmospheric water vapor delay by incorporating terrain elevation information / B. Xu in Journal of geodesy, vol 85 n° 9 (September 2011)Permalink4D GPS water vapor tomography: new parameterized approaches / Donat Perler in Journal of geodesy, vol 85 n° 8 (August 2011)Permalink