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Digital camera performance where spatial resolution is determined by the optical component / G.H. Thomson in Photogrammetric record, vol 25 n° 129 (March - May 2010)
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Titre : Digital camera performance where spatial resolution is determined by the optical component Type de document : Article/Communication Auteurs : G.H. Thomson, Auteur Année de publication : 2010 Article en page(s) : pp 42 - 46 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse comparative
[Termes IGN] caméra numérique
[Termes IGN] capteur spatial
[Termes IGN] diffraction
[Termes IGN] pouvoir de résolution géométrique
[Termes IGN] système optique
[Termes IGN] test de performanceRésumé : (Auteur) The spatial resolution attributed to digital cameras is usually based on the number or size of the pixels in the sensor. On closer examination it can often be shown that the real limit to the level of detail recorded by a camera will in practice be due to the performance of the optical system. An example of how this happens is given with a comparison between two satellite camera systems. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2010-062 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2009.00566.x Date de publication en ligne : 11/03/2010 En ligne : https://doi.org/10.1111/j.1477-9730.2009.00566.x Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30258
in Photogrammetric record > vol 25 n° 129 (March - May 2010) . - pp 42 - 46[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-2010011 RAB Revue Centre de documentation En réserve L003 Disponible Acoustics & GPS: real-time scoring and classification of munitions / M. Cardoza in Inside GNSS, vol 5 n° 1 (January - February 2010)
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Titre : Acoustics & GPS: real-time scoring and classification of munitions Type de document : Article/Communication Auteurs : M. Cardoza, Auteur ; et al., Auteur Année de publication : 2010 Article en page(s) : 10 p. ; pp 28 - 37 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] acoustique
[Termes IGN] armement
[Termes IGN] Etats-Unis
[Termes IGN] positionnement par GPS
[Termes IGN] test de performanceRésumé : (Auteur) The development of more precise weapons with GPS on board has created a corresponding need for more precise and flexible methods of testing them. Here’s a look inside the development of a highly accurate, real-time, portable, and low-cost alternative to traditional weapons testing systems. It incorporates state-of-the-art acoustic, GNSS, and data processing and analysis technologies and has been undergoing tests at the U.S. Army Yuma Proving Ground since May 2009. Copyright Gibbons Media & Research LLC Numéro de notice : A2010-616 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33556
in Inside GNSS > vol 5 n° 1 (January - February 2010) . - 10 p. ; pp 28 - 37[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 159-2010011 SL Revue Centre de documentation Revues en salle Disponible Documents numériques
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Titre : Expériences d’appariement d’images avec SIFT Titre original : Image matching experiments with SIFT Type de document : Rapport Auteurs : Arnaud Le Bris , Auteur Editeur : Saint-Mandé : Institut Géographique National - IGN (2008-2011) Année de publication : 2010 Importance : 163 p. Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] appariement d'images
[Termes IGN] extraction de points
[Termes IGN] méthode robuste
[Termes IGN] SIFT (algorithme)
[Termes IGN] test de performanceIndex. décimale : 35.20 Traitement d'image Résumé : (auteur) SIFT (Scale Invariant Feature Transform) est à la fois une méthode d’extraction de points d’intérêt et d’appariement de ces points entre deux images. Le comportement de l’image au voisinage de chaque point détecté est décrit au moyen d’un descripteur qui lui est associé, la mise en correspondance des points homologues s’effectuant par la suite dans l’espace de ces descripteurs. SIFT est un algorithme robuste, en particulier aux variations d’échelle, aux rotations (2D), au bruit ainsi quà des transformations affines “légères”. Il est en revanche assez sensible au phénomène de diachronisme autrement dit au fait que les images n’aient pas été acquises à la même période et présentent un aspect différent. SIFT a donc fait l’objet de tests sur différents types d’images (aérien, satellite, terrestre) dans différents contextes (images de même résolution ou non, diachronisme) et pour différentes applications (extraction de points de liaison pour l’aérotriangulation, constitution automatique de tableaux d’assemblage ou recalage automatique d’images). Numéro de notice : 13109 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE/INFORMATIQUE Nature : Rapport d'étude technique nature-HAL : Rapport DOI : sans En ligne : https://hal.science/hal-02370256 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103291 One year in orbit: GIOVE-B E1 CBOC signal quality assessment / M. Sollner in GPS world, vol 20 n° 9 (September 2009)
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Titre : One year in orbit: GIOVE-B E1 CBOC signal quality assessment Type de document : Article/Communication Auteurs : M. Sollner, Auteur ; C. Kurzhals, Auteur ; W. Kogler, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : 8 p. ; pp 28 - 38 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] qualité du signal
[Termes IGN] signal GNSS
[Termes IGN] test de performanceRésumé : (Editeur) The second GALILEO test satellite, GIOVE-B, was launched on April 27,2008, and began transmitting navigation signals a few days later. It joined its older sibling, GIOVE-A, which was placed in orbit over two years earlier. [...] The launches are expected to occur by the end of 2010. But before the In-Orbit Validation (IOV) phase can begin, a thorough analysis of the performance of the GIOVE satellites must be carried out to minimize any difficulties with the IOV satellites. This includes monitoring and assessing the different signals broadcast by the satellites. The GIOVE satellites can transmit on all three Galileo frequencies, E5, E6, and E1 (also known as L1) but only on two simultaneously (either E1-E5 or E1-E6). A variety of modulation types can be transmitted on the different frequencies by both satellites to test their use for the different Galileo services to be implemented for the operational constellation. These include alternative binary offset carrier (BOC) and quadrature phase shift keying on E5 and cosine BOC (BOCc) and binary phase shift keying on E6. On E1, the satellites have different capabilities. Although both satellites can transmit BOCc on this frequency, GIOVE-A can additionally transmit a single BOC signal with a subcarrier frequency of 1.023 MHz and a spreading code chipping rate of 1.023 MHz (BOC(1,1)) whereas GIOVE-B transmits a more versatile multiplexed composite BOC or CBOC, which linearly combines BOC(1,1) and BOC(6,1). The CBOC signal is being transmitted by GIOVE-B to explore its performance, usability, and any possible side effects including its use in receivers designed to track a BOC(1,1) signal. GIOVE-B has now been in orbit for just over one year. How well is it performing? In particular, what can we say about one of GIOVE-B's pioneering features: its E1 CBOC signal? In this month's column, we take a detailed look at a particular monitoring and assessment program set up to examine the GIOVE-B signals and discuss some of its initial CBOC results. The successful operation of this program bodes well for its use in future validation campaigns. Copyright Questex Media Group Numéro de notice : A2009-348 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29978
in GPS world > vol 20 n° 9 (September 2009) . - 8 p. ; pp 28 - 38[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-09091 SL Revue Centre de documentation Revues en salle Disponible The WAAS L5 signal: an assessment of its behavior and potential end use / H. Rho in GPS world, vol 20 n° 5 (May 2009)
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Titre : The WAAS L5 signal: an assessment of its behavior and potential end use Type de document : Article/Communication Auteurs : H. Rho, Auteur ; R.B. Langley, Auteur Année de publication : 2009 Article en page(s) : pp 42 - 48 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] signal GPS
[Termes IGN] signal multidimensionnel
[Termes IGN] test de performance
[Termes IGN] Wide Area Augmentation SystemRésumé : (Auteur) The recent launch of the GPS Block IIR-20(M) satellite and the commissioning of its L5 demonstration payload herald the beginning of a bright new era in space-based positioning, navigation, and timing. The new satellite signal is anticipated to provide better-quality range measurements and possibly improve the tracking performance of a GPS receiver compared with current civil L1 and L2 signals through use of improved signal structures. The L5 signal will be standard on the future Block IIF and Block III satellites.
However, some readers may be surprised to learn that L5 signals have been continuously transmitted by a pair of satellites for the past several years. The geostationary Earth-orbiting (GEO) satellites used by the U.S. Federal Aviation Administration's (FAA's) Wide Area Augmentation System to provide enhanced integrity and accuracy include not only an L1 payload but an L5 payload as well. While the WAAS L5 signals have been broadcast from space for some time, they did not come from a satellite in medium Earth orbit, and so it was necessary to include the demonstration payload on the GPS Block IIR-20(M) satellite to guarantee the L5 frequency filing with the International Telecommunication Union.
There are some differences between the WAAS L5 signals and the future fully fledged GPS L5 signals. The WAAS L5 signals only use a single-channel carrier (there is no quadrature or Q channel) and the data rate is 250 bits per second (bps) rather than 50 bps. The WAAS signals are actually generated on the ground and relayed through the GEOs using a "bent pipe" approach. The FAA uses the L5 signals, in conjunction with the L1 signals, to compute ionospheric delays as part of the closed-loop control of the broadcast signals.
Although the WAAS L5 signals are not yet intended for end users, can they be used now for positioning and navigation and, if so, are there any caveats? In this month's column, I am joined by one of my graduate students, Hyun-ho Rho, who has looked at the WAAS L5 transmissions, examining their signal strengths, multipath characteristics, and instrumental bias issues. Precise positioning performance of WAAS pseudoranges has also been assessed as an independent check on instrumental bias compensation by the WAAS control segment. The favorable results point to a future of the L5 signal, on both the WAAS satellites and the next-generation GPS satellites, which is bright indeed. Copyright Questex Media GroupNuméro de notice : A2009-178 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29808
in GPS world > vol 20 n° 5 (May 2009) . - pp 42 - 48[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-09051 SL Revue Centre de documentation Revues en salle Disponible Evaluation ponctuelle des performances du réseau TERIA / Stéphane Durand in XYZ, n° 118 (mars - mai 2009)PermalinkMulti-band test robotic total stations: Trimble VX, Part 4 / L. Van Der Poel in Geoinformatics, vol 12 n° 1 (01/01/2009)PermalinkPermalinkTrajectory determination and analysis in sports by satellite and inertial navigation / Adrian Wägli (2009)PermalinkMulti-band test robotic total stations: Leica TPS 1200+, part 3 / L. Van Der Poel in Geoinformatics, vol 11 n° 8 (01/12/2008)PermalinkRadiometric calibration and characterization of large-format digital photogrammetric sensors in a test field / Lauri Markelin in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 12 (December 2008)PermalinkMulti-brand test robotic total stations: Sokkia SRX robotic total station, part 2 / N. Rengers in Geoinformatics, vol 11 n° 7 (01/11/2008)PermalinkDevelopment and testing of a generic sensor model for pushbroom satellite imagery / T. Weser in Photogrammetric record, vol 23 n° 123 (September - November 2008)PermalinkMulti-user test robotic total station: TOPCON IS-03 imaging station, part 1 / N. Rengers in Geoinformatics, vol 11 n° 6 (01/09/2008)PermalinkThe view from Chilbolton: in-orbit test results from the second Galileo satellite / G. Gatti in Inside GNSS, vol 3 n° 6 (September 2008)Permalink