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Noise simulation and correction in synthetic airborne TIR Data for mineral quantification / Christoph Hecker in IEEE Transactions on geoscience and remote sensing, vol 54 n° 3 (March 2016)
[article]
Titre : Noise simulation and correction in synthetic airborne TIR Data for mineral quantification Type de document : Article/Communication Auteurs : Christoph Hecker, Auteur ; Dean Riley, Auteur ; Mark Van Der Meijde, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 1545 - 1553 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] erreur systématique
[Termes IGN] image aérienne
[Termes IGN] image hyperspectrale
[Termes IGN] image thermique
[Termes IGN] prospection minérale
[Termes IGN] quartz
[Termes IGN] rapport signal sur bruit
[Termes IGN] rayonnement infrarouge thermique
[Termes IGN] régression
[Termes IGN] simulationRésumé : (Auteur) Rock-forming minerals (such as feldspar and quartz) can be identified and quantified from thermal infrared (TIR) laboratory spectroscopy using spectral models. This paper uses synthetic airborne TIR spectra to test whether the hyperspectral Spatially Enhanced Broadband Array Spectrograph System (SEBASS) would theoretically be able to detect quartz and feldspar minerals and quantitatively predict mineral modes in felsic igneous rocks. Data from a previous laboratory study were used to simulate TIR spectra with band locations and noise levels of the SEBASS sensor. The quantitative partial least squares regression (PLSR) models from that study were applied to newly created synthetic SEBASS data, and results were compared with the predictions from the previous study. Predicted compositions based on SEBASS band positions are nearly identical (ρ = 0.995) to those based on laboratory resolution. Results are still reliable [prediction errors within 0.4% (absolute)] to the original laboratory PLSR predictions when adding up to 1% noise (about five times the SEBASS noise level) to the synthetic data. Prediction errors rapidly increase when noise levels beyond 1% are used. These results show that SEBASS' spectral resolution, spectral coverage, and signal-to-noise levels are sufficient to quantitatively predict quartz and feldspar amounts, and feldspar compositions with models based on PLSR. Spectral distortions, such as reduced spectral contrast, tilts, and vertical shifts, must be compensated for before these quantitative models are applied. A mean and standard deviation (MASD) normalization is proposed using a set of ground data for compensating systematic errors that are common to all image pixels. Numéro de notice : A2016-124 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2482386 En ligne : https://doi.org/10.1109/TGRS.2015.2482386 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80005
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 3 (March 2016) . - pp 1545 - 1553[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2016031 SL Revue Centre de documentation Revues en salle Disponible Correcting distortion of polarimetric SAR data induced by ionospheric scintillation / Jun Su Kim in IEEE Transactions on geoscience and remote sensing, vol 53 n° 12 (December 2015)
[article]
Titre : Correcting distortion of polarimetric SAR data induced by ionospheric scintillation Type de document : Article/Communication Auteurs : Jun Su Kim, Auteur ; Konstantinos Panagiotis Papathanassiou, Auteur ; Rolf Scheiber, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 6319 - 6335 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande L
[Termes IGN] bande P
[Termes IGN] correction ionosphérique
[Termes IGN] données polarimétriques
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image radar moirée
[Termes IGN] polarimétrie radar
[Termes IGN] scintillationRésumé : (auteur) A correction methodology for distortions induced by ionospheric scintillation on fully polarimetric synthetic aperture radar (SAR) data is proposed. The correction is based on deriving the phase distortion induced by the ionosphere from Faraday rotation estimates. The estimated phase distortion is then used for correction. In order to compensate the phase and time-Doppler history distortions, the correction has to be performed at the slant range of the ionospheric layer, i.e., on partially focused single-look complex data. Accordingly, the performance of the proposed correction methodology depends, among other factors, on knowledge of the altitude of the effective ionospheric layer (assuming the thin ionospheric layer model). Its estimation from the SAR data itself is therefore also addressed. The methodology was applied and validated on simulated P-band data for various ionospheric conditions and on real L-band data acquired by the Advanced Land Observation Satellite Phased Array L-band SAR (PALSAR). Numéro de notice : A2015-842 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2431856 Date de publication en ligne : 05/08/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2431856 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79186
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 12 (December 2015) . - pp 6319 - 6335[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015121 SL Revue Centre de documentation Revues en salle Disponible Network-based estimation of time-dependent noise in GPS position time series / Ksenia Dimitrieva in Journal of geodesy, vol 89 n° 6 (June 2015)
[article]
Titre : Network-based estimation of time-dependent noise in GPS position time series Type de document : Article/Communication Auteurs : Ksenia Dimitrieva, Auteur ; Paul Segall, Auteur ; Charles DeMets, Auteur Année de publication : 2015 Article en page(s) : pp 591 - 606 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] bruit blanc
[Termes IGN] bruit rose
[Termes IGN] données GPS
[Termes IGN] estimation statistique
[Termes IGN] filtre de Kalman
[Termes IGN] incertitude des données
[Termes IGN] rapport signal sur bruit
[Termes IGN] réseau géodésique local
[Termes IGN] série temporelle
[Termes IGN] signal GPS
[Termes IGN] vitesseRésumé : (auteur) Some estimates of GPS velocity uncertainties are very low, Numéro de notice : A2015-351 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0801-9 Date de publication en ligne : 24/03/2015 En ligne : https://doi.org/10.1007/s00190-015-0801-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76736
in Journal of geodesy > vol 89 n° 6 (June 2015) . - pp 591 - 606[article]Eliminating diffraction effects during multi-frequency correction in global navigation satellite systems / M.V. Tinin in Journal of geodesy, vol 89 n° 5 (May 2015)
[article]
Titre : Eliminating diffraction effects during multi-frequency correction in global navigation satellite systems Type de document : Article/Communication Auteurs : M.V. Tinin, Auteur Année de publication : 2015 Article en page(s) : pp 491 - 503 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] correction du signal
[Termes IGN] correction ionosphérique
[Termes IGN] diffraction
[Termes IGN] positionnement par GPS
[Termes IGN] résidu
[Termes IGN] signal GNSS
[Termes IGN] signal multidimensionnelRésumé : (auteur) In the geometrical optics approximation, the ionospheric part of error in measuring phase and code delays of the satellite signal may be represented as a rapidly decreasing series in inverse power of frequency. Such a simple frequency dependence allows us to use multi-frequency measurements for eliminating the error in such multi-frequency Global Navigation Satellite Systems as GPS, GLONASS, BeiDou, and Galileo. However, the elimination of errors is handicapped by diffraction effects during signal propagation through turbulent ionospheric plasma. The numerical simulation has shown that when using the spatial processing in the form of Fresnel inversion the transition from dual-frequency to triple-frequency measurements reduces the average error of measurement. Yet fluctuations of the error diminish only if the inner scale exceeds the Fresnel radius. In the opposite case of excess of the Fresnel radius over the inner scale, the random component of the residual error is growing during the transition to triple-frequency measurements. The numerical simulation results also suggest that the Fresnel spatial processing in dual-frequency measurements at the optimal distance to the virtual screen can reduce the average error from centimeter to submillimeter level, which renders the transition to triple-frequency measurements unnecessary. The study of the residual error dependence on the distance from the virtual screen to the observer has revealed that the optimum value of this distance may be found from the minimum condition of amplitude scintillation index of the processed signal. The signal thus processed may be utilized both in geodetic precise measurements and in diagnostics of the lower atmosphere. Numéro de notice : A2015-349 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0794-4 En ligne : https://doi.org/10.1007/s00190-015-0794-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76723
in Journal of geodesy > vol 89 n° 5 (May 2015) . - pp 491 - 503[article]Vegetation sensing using GPS-interferometric reflectometry: theoretical effects of canopy parameters on signal-to-noise ratio data / C.C. Chew in IEEE Transactions on geoscience and remote sensing, vol 53 n° 5 (mai 2015)
[article]
Titre : Vegetation sensing using GPS-interferometric reflectometry: theoretical effects of canopy parameters on signal-to-noise ratio data Type de document : Article/Communication Auteurs : C.C. Chew, Auteur ; E.E. Small, Auteur ; K. Larson, Auteur ; V. Zavorotny, Auteur Année de publication : 2015 Article en page(s) : pp 2755 - 2764 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] couvert végétal
[Termes IGN] humidité du sol
[Termes IGN] rapport signal sur bruit
[Termes IGN] réflectométrie par GNSS
[Termes IGN] signal GPS
[Termes IGN] végétationRésumé : (Auteur) The potential to use GPS signal-to-noise ratio (SNR) data to estimate changes in vegetation surrounding a ground-based antenna is evaluated. A 1-D plane-stratified model that simulates the response of GPS SNR data to changes in both soil moisture and vegetation is presented. The model is validated against observations of SNR data from four field sites with varying vegetation cover. Validation shows that the average correlation between modeled and observed SNR data is higher than the average correlation between concurrent SNR observations from different satellite tracks at a site. The model also reproduces variations in the SNR metrics amplitude, phase, and effective reflector height over a range of vegetation wet weights from 0 to 4 kg · m-2, with r2 values of 0.79, 0.84, and 0.62, respectively. Model simulations indicate that the amplitude of SNR oscillations may be used to estimate vegetation amount when vegetation wet weight is below 1.5 kg · m-2. When vegetation wet weight exceeds 1.5 kg · m-2, the sensitivity of amplitude to changes in vegetation amount decreases. Phase of SNR oscillations also varies consistently with vegetation up to 1.5 kg · m-2. However, phase is also very sensitive to soil moisture variations, thus limiting its utility for estimating vegetation. Effective reflector height is not a consistent indicator of vegetation change. Beyond 1.5 kg · m-2, the constant frequency assumption used to characterize SNR fluctuations does not adequately describe observed data. A more complex approach than the standard SNR metrics used here is required to extend GPS-Interferometric Reflectometry sensing to thicker canopies. Numéro de notice : A2015-517 Affiliation des auteurs : non IGN Thématique : FORET/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2364513 En ligne : https://doi.org/10.1109/TGRS.2014.2364513 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77523
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 5 (mai 2015) . - pp 2755 - 2764[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015051 RAB Revue Centre de documentation En réserve L003 Disponible Galileo E1 and E5a Performance for multi-frequency, multi-constellation GBAS / Mihaela-Simona Circiu in GPS world, vol 26 n° 4 (April 2015)PermalinkThe guided bilateral filter: When the joint/cross bilateral filter becomes robust / Laurent Caraffa in IEEE Transactions on image processing, vol 24 n° 4 (April 2015)PermalinkWuhan ionospheric oblique-incidence sounding system and its new application in localization of ionospheric irregularities / Shu-Zhu Shi in IEEE Transactions on geoscience and remote sensing, vol 53 n° 4 (April 2015)PermalinkLevelling co-located GNSS and tide gauge stations using GNSS reflectometry / Alvaro Santamaria Gomez in Journal of geodesy, vol 89 n° 3 (March 2015)PermalinkThe Guided Bilateral Filter: When the Joint/Cross Bilateral Filter Becomes Robust / Laurent Caraffa (2015)PermalinkA Realistic and Easy-to-Implement Weighting Model for GPS Phase Observations / Xiaoguang Luo in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)Permalink3-Pol polarimetric weather measurements with agile-beam phased-array radars / Verónica Santalla del Rio in IEEE Transactions on geoscience and remote sensing, vol 52 n° 9 Tome 2 (September 2014)PermalinkImpact of signal contamination on the adaptive detection performance of local hyperspectral anomalies / Stefania Matteoli in IEEE Transactions on geoscience and remote sensing, vol 52 n° 4 (April 2014)PermalinkAnalyse des séries temporelles de coordonnées des sites multi-techniques (SLR, VLBI, DORIS et GPS) / Bachir Gourine in Bulletin des sciences géographiques, n° 29 (janvier - juin 2014)PermalinkEffects of atmospheric stability and wind fetch on microwave sea echoes / Yunhua Wang in IEEE Transactions on geoscience and remote sensing, vol 52 n° 2 (February 2014)Permalink