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Positioning in challenging environments using ultra-wideband sensor networks / Zoltan Koppanyi in GPS world, vol 26 n° 3 (March 2015)
[article]
Titre : Positioning in challenging environments using ultra-wideband sensor networks Type de document : Article/Communication Auteurs : Zoltan Koppanyi, Auteur ; Charles K. Toth, Auteur ; Dorota A. Grejner-Brzezinska, Auteur Année de publication : 2015 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] GNSS assisté pour la navigation
[Termes IGN] onde radioélectrique
[Termes IGN] positionnement en intérieur
[Termes IGN] réseau de capteursRésumé : (auteur) [...] Conventional radio transmissions use a variety of modulation techniques but most involve varying the amplitude, frequency and/or phase of a sinusoidal carrier wave. But in the late 1960s, it was shown that one could generate a signal as a sequence of very short pulses, which results in the signal energy being spread over a large part of the radio spectrum. Initially called pulse radio, the technique has become known as impulse radio ultra-wideband or just ultra-wideband (UWB) for short and by the 1990s a variety of practical transmission and reception technologies had been developed.
The use of large transmission bandwidths offers a number of benefits, including accurate ranging and that application in particular is being actively developed for positioning and navigation in environments that are challenging to GNSS such as indoors and built-up areas. In this month’s column, we take a look at the work being carried out in this area by a team of researchers at The Ohio State University.Numéro de notice : A2015-265 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT/SOCIETE NUMERIQUE Nature : Article DOI : sans En ligne : http://gpsworld.com/innovation-where-are-we/ Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76315
in GPS world > vol 26 n° 3 (March 2015)[article]Precise point positioning using multi-constellation GNSS observations for kinematic applications / Mahmoud Abd-El-Rahman in Journal of applied geodesy, vol 9 n° 1 (March 2015)
[article]
Titre : Precise point positioning using multi-constellation GNSS observations for kinematic applications Type de document : Article/Communication Auteurs : Mahmoud Abd-El-Rahman, Auteur ; Ahmed El-Rabbany, Auteur Année de publication : 2015 Article en page(s) : pp 15 - 26 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] erreur systématique
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] simple différenceRésumé : (auteur) Traditional precise point positioning (PPP) is commonly based on un-differenced ionosphere-free linear combination of Global Positioning System (GPS) observations. Unfortunately, for kinematic applications, GPS often experiences poor satellite visibility or weak satellite geometry in urban areas. To overcome this limitation, we developed a PPP model, which combines the observations of three global navigation satellite systems (GNSS), namely GPS, GLONASS and Galileo. Both un-differenced and between-satellite single-difference (BSSD) ionosphere-free linear combinations of pseudorange and carrier phase GNSS measurements are processed. The performance of the combined GNSS PPP solution is compared with the GPS-only PPP solution using a real test scenario in downtown Kingston, Ontario. Inter-system biases between GPS and the other two systems are also studied and obtained as a byproduct of the PPP solution. It is shown that the addition of GLONASS observations improves the kinematic PPP solution accuracy in comparison with that of GPS-only solution. However, the contribution of adding Galileo observations is not significant due to the limited number of Galileo satellites launched up to date. In addition, BSSD solution is found to be superior to that of traditional un-differenced model. Numéro de notice : A2015-027 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2014-0021 En ligne : http://www.degruyter.com/view/j/jag.2015.9.issue-1/jag-2014-0021/jag-2014-0021.x [...] Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76880
in Journal of applied geodesy > vol 9 n° 1 (March 2015) . - pp 15 - 26[article]Review and principles of PPP-RTK methods / Peter J.G. Teunissen in Journal of geodesy, vol 89 n° 3 (March 2015)
[article]
Titre : Review and principles of PPP-RTK methods Type de document : Article/Communication Auteurs : Peter J.G. Teunissen, Auteur ; Amir Khodabandeh, Auteur Année de publication : 2015 Article en page(s) : pp 217 - 240 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse comparative
[Termes IGN] double différence
[Termes IGN] estimateur
[Termes IGN] méthode de mesure
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïtéRésumé : (auteur) PPP-RTK is integer ambiguity resolution-enabled precise point positioning. In this contribution, we present the principles of PPP-RTK, together with a review of different mechanizations that have been proposed in the literature. By application of S-system theory, the estimable parameters of the different methods are identified and compared. Their interpretation is essential for gaining a proper insight into PPP-RTK in general, and into the role of the PPP-RTK corrections in particular. We show that PPP-RTK is a relative technique for which the ‘single-receiver user’ integer ambiguities are in fact double-differenced ambiguities. We determine the transformational links between the different methods and their PPP-RTK corrections, thereby showing how different PPP-RTK methods can be mixed between network and users. We also present and discuss four different estimators of the PPP-RTK corrections. It is shown how they apply to the different PPP-RTK models, as well as why some of the proposed estimation methods cannot be accepted as PPP-RTK proper. We determine analytical expressions for the variance matrices of the ambiguity-fixed and ambiguity-float PPP-RTK corrections. This gives important insight into their precision, as well as allows us to discuss which parts of the PPP-RTK correction variance matrix are essential for the user and which are not. Numéro de notice : A2015-336 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0771-3 Date de publication en ligne : 13/11/2014 En ligne : https://doi.org/10.1007/s00190-014-0771-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76704
in Journal of geodesy > vol 89 n° 3 (March 2015) . - pp 217 - 240[article]Python GNSS receiver: An object-oriented software platform suitable for multiple receivers / Eliot Wycoff in GPS world, vol 26 n° 2 (February 2015)
[article]
Titre : Python GNSS receiver: An object-oriented software platform suitable for multiple receivers Type de document : Article/Communication Auteurs : Eliot Wycoff, Auteur ; Yuting Ng, Auteur ; Grace Xingxin Gao, Auteur Année de publication : 2015 Article en page(s) : pp 52 - 57 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] géopositionnement
[Termes IGN] Python (langage de programmation)
[Termes IGN] récepteur GNSSRésumé : (éditeur) In this month column, we take a look at how Python has been used to develop a software-defined GNSS receiver - one well-suited to processing data from a network of receiver front ends. Numéro de notice : A2015-061 Affiliation des auteurs : non IGN Thématique : INFORMATIQUE/POSITIONNEMENT Nature : Article DOI : sans En ligne : http://gpsworld.com/innovation-python-gnss-receiver/ Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75313
in GPS world > vol 26 n° 2 (February 2015) . - pp 52 - 57[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Evaluation of Precise Point Positioning accuracy under large total electron content variations in equatorial latitudes / I. Rodriguez-Bilbao in Advances in space research, vol 55 n° 2 (January 2015)
[article]
Titre : Evaluation of Precise Point Positioning accuracy under large total electron content variations in equatorial latitudes Type de document : Article/Communication Auteurs : I. Rodriguez-Bilbao, Auteur ; B. Moreno Monge, Auteur ; G. Rodriguez-Caderot, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 605 - 616 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] équateur (géodésie)
[Termes IGN] estimation de précision
[Termes IGN] positionnement ponctuel précis
[Termes IGN] teneur totale en électronsRésumé : (auteur) The ionosphere is one of the largest contributors to errors in GNSS positioning. Although in Precise Point Positioning (PPP) the ionospheric delay is corrected to a first order through the ‘iono-free combination’, significant errors may still be observed when large electron density gradients are present. To confirm this phenomenon, the temporal behavior of intense fluctuations of total electron content (TEC) and PPP altitude accuracy at equatorial latitudes are analyzed during four years of different solar activity. For this purpose, equatorial plasma irregularities are identified with periods of high rate of change of TEC (ROT). The largest ROT values are observed from 19:00 to 01:00 LT, especially around magnetic equinoxes, although some differences exist between the stations depending on their location. Highest ROT values are observed in the American and African regions. In general, large ROT events are accompanied by frequent satellite signal losses and an increase in the PPP altitude error during years 2001, 2004 and 2011. A significant increase in the PPP altitude error RMS is observed in epochs of high ROT with respect to epochs of low ROT in years 2001, 2004 and 2011, reaching up to 0.26 m in the 19:00–01:00 LT period. Numéro de notice : A2015-298 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2014.11.004 En ligne : https://doi.org/10.1016/j.asr.2014.11.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76462
in Advances in space research > vol 55 n° 2 (January 2015) . - pp 605 - 616[article]Augmenting vehicle localization accuracy with cameras and 3D road infrastructure database / Lijun Wei (2015)PermalinkPermalinkA precise state transition model for aircraft navigation / Abhijit Sinha in Geomatica, vol 68 n° 4 (December 2014)PermalinkReliability analysis of the results of RTN GNSS surveys of building structures using indirect methods of measurement / Robert Krzyzek in Geodesy and cartography, vol 63 n° 2 (December 2014)PermalinkA bright idea: testing the feasibility of positionning using ambient light / J. Liu in GPS world, vol 25 n° 11 (novembre 2014)PermalinkNon-linear motions of Australian geodetic stations induced by non-tidal ocean loading and the passage of tropical cyclones / A. Mémin in Journal of geodesy, vol 88 n° 10 (October 2014)PermalinkSingle frequency GPS/Galileo precise point positioning using un-differenced and between-satellite single difference measurements / Akram Afifi in Geomatica, vol 68 n° 3 (September 2014)PermalinkAn assisting, constrained 3D navigation technique for multiscale virtual 3D city models / Dieter Hildebrandt in Geoinformatica, vol 18 n° 3 (July 2014)PermalinkCompression of trajectory data: a comprehensive evaluation and new approach / Jonathan Muckell in Geoinformatica, vol 18 n° 3 (July 2014)PermalinkPredictive policing / Jeremy Heffner in GEO: Geoconnexion international, vol 13 n° 7 (July 2014)Permalink