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Bidirectional reflectance of Earth targets: evaluation of analytical models using a large set of spaceborne measurements with emphasis on the Hot Spot / F. Maignan in Remote sensing of environment, vol 90 n° 2 (30/03/2004)
[article]
Titre : Bidirectional reflectance of Earth targets: evaluation of analytical models using a large set of spaceborne measurements with emphasis on the Hot Spot Type de document : Article/Communication Auteurs : F. Maignan, Auteur ; François-Marie Bréon, Auteur ; R. Lacaze, Auteur Année de publication : 2004 Article en page(s) : pp 210 - 220 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Rayonnement électromagnétique
[Termes IGN] albedo
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] image ADEOS-POLDER
[Termes IGN] réflectance
[Termes IGN] rétrodiffusion
[Termes IGN] tâche claire
[Termes IGN] transfert radiatifRésumé : (Auteur) Multidirectional observation from the spacebome POLDER (Polarization and Directionality of the Earth Reflectance) instrument makes it possible to measure the bidirectional reflectance of a large variety of Earth targets. A careful selection of cloud-free measurements with a large directional coverage lead to about 22,000 sets of measured Bidirectional Reflectance Distribution Functions (BRDFs). This data set is used to evaluate the ability of analytical models to reproduce the observed directional signatures. Among those evaluated, the best models appear to be the three-parameter linear Ross-Li model, and the nonlinear Rahman-Pinty-Verstraete (RPV) model. On the other hand, all models fail to accurately reproduce the sharp reflectance increase (hot spot) close to the backscattering direction. Based on physical considerations, we suggest a modification of the Ross-Li model, without adding a free parameter, to account for the complex radiative transfer within the canopy that leads to the hot spot signature. The modified linear model performs better than all others, including the RPV nonlinear model. Although the correction modifies the retrieved directional signature parameters, it does not change significantly the surface albedo estimates. Numéro de notice : A2004-142 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.12.006 En ligne : https://doi.org/10.1016/j.rse.2003.12.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26669
in Remote sensing of environment > vol 90 n° 2 (30/03/2004) . - pp 210 - 220[article]Assessing the potential of space-borne C-band SAR data for spatial soil moisture information over a large area / S.A. Romshoo in Geocarto international, vol 19 n° 1 (March - May 2004)
[article]
Titre : Assessing the potential of space-borne C-band SAR data for spatial soil moisture information over a large area Type de document : Article/Communication Auteurs : S.A. Romshoo, Auteur ; K. Musiake, Auteur Année de publication : 2004 Article en page(s) : pp 65 - 75 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse en composantes principales
[Termes IGN] humidité du sol
[Termes IGN] image ERS-SAR
[Termes IGN] image Radarsat
[Termes IGN] modèle de diffusion du rayonnement
[Termes IGN] rétrodiffusion
[Termes IGN] zone humideRésumé : (Auteur) The backscattering coefficient ä from a time series of ERS-2 SAR data showed high correlation (r 2 =0.94) and high sensitivity to the observed surface soil moisture at a field scale. The observations agreed well with the simulations from the two surface scattering models tested in the study area. A single coincidence of the ERS-2 and RADARSAT missions, with two different polarizations, provided an opportunity to estimate soil moisture over a large area by inverting the Dubois model. The estimates were validated with the field observations over a small area and are in good agreement with standard error of estimate (SEE) equal to 1.01 cm3 cm-3. Furthermore, different soil moisture estimation methods were tested and compared with the observations to better understand the temporal and spatial variability of this important parameter. Soil moisture at a point was simulated using three hydrological models and compared with the radar backscattering and the point observations. There is a large variation in the responses among them. Simple statistical approaches viz., coefficient of variation and principal component analysis were used for mapping the spatial patterns of soil moisture over a large area using a time series of ERS-2 data. These simple methods helped to map areas where the moisture availability is not varying much. This information about soil moisture distribution is of vital importance to the hydrological processes especially the variable source area concept. Numéro de notice : A2004-233 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040408542300 Date de publication en ligne : 02/01/2008 En ligne : https://doi.org/10.1080/10106040408542300 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26760
in Geocarto international > vol 19 n° 1 (March - May 2004) . - pp 65 - 75[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 059-04011 RAB Revue Centre de documentation En réserve L003 Disponible Phenomenological analysis of simulated signals observed over shaded areas in an urban scene / Christophe Miesch in IEEE Transactions on geoscience and remote sensing, vol 42 n° 2 (February 2004)
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Titre : Phenomenological analysis of simulated signals observed over shaded areas in an urban scene Type de document : Article/Communication Auteurs : Christophe Miesch, Auteur ; Xavier Briottet , Auteur ; Yann H. Kerr, Auteur Année de publication : 2004 Article en page(s) : pp 434 - 442 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] bande spectrale
[Termes IGN] diffusion du rayonnement
[Termes IGN] image à haute résolution
[Termes IGN] image panchromatique
[Termes IGN] milieu urbain
[Termes IGN] ombre
[Termes IGN] réfraction atmosphérique
[Termes IGN] scène
[Termes IGN] simulation
[Termes IGN] transfert radiatifRésumé : (Auteur) This paper analyzes the signal measured by optical remote sensors when acquiring data over a shaded part of an urban scene. The signal is much lower for this kind of target than for others because there is no direct downward irradiance. Here, a simple urban scene is considered with a shaded area. The signal observed by a high spatial resolution satellite sensor over an ordinary panchromatic band (500-700 nm) is computed thanks to a radiative transfer code [advanced modeling of the atmospheric radiative transfer for inhomogeneous surfaces (Amartis)] capable of dealing with ground topography and heterogeneity. The signal is analyzed, and it appears that environmental effects play a significant role. Moreover, because of the scattering that occurs at shorter wavelengths, it is also shown that a widening of the band to 440 nm sharpens the difference between signals coming from two different ground types (for whose the difference of reflectance is constant and equal to 0.1) by about 10%. This demonstrates that the band widening may be beneficial to observation in shadow, mainly because of scattering effects. A more realistic scene is also considered, in which each part is associated with realistic spectral properties. This simply shows the importance of the thematic in the choice of band, as it determines the effect of the widening. Numéro de notice : A2004-138 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2003.814916 En ligne : https://doi.org/10.1109/TGRS.2003.814916 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26665
in IEEE Transactions on geoscience and remote sensing > vol 42 n° 2 (February 2004) . - pp 434 - 442[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-04021 RAB Revue Centre de documentation En réserve L003 Disponible Vegetation canopy anisotropy at 1.4 GHz / B.K. Hornbuckle in IEEE Transactions on geoscience and remote sensing, vol 41 n° 10 (October 2003)
[article]
Titre : Vegetation canopy anisotropy at 1.4 GHz Type de document : Article/Communication Auteurs : B.K. Hornbuckle, Auteur ; A.W. England, Auteur ; R.D. DE Roo, Auteur ; M.A. Fischman, Auteur ; D.L. Boprie, Auteur Année de publication : 2003 Article en page(s) : pp 2211 - 2223 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] angle d'incidence
[Termes IGN] anisotropie
[Termes IGN] couvert végétal
[Termes IGN] diffusion du rayonnement
[Termes IGN] humidité du sol
[Termes IGN] maïs (céréale)
[Termes IGN] modèle de transfert radiatif
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) We investigate anisotropy in 1.4 GHz brightness induced by a field corn vegetation canopy. We find that both polarizations of brightness are isotropic in azimuth during most of the growing season. When the canopy is senescent, the brightness is a strong function of row direction. On the other hand, the 1.4 GHz brightness is anisotropic in elevation : an isotropic zero-order radiative transfer model could not reproduce the observed change in brightness with incidence angle. Significant scatter darkening was found. The consequence of unanticipated scatter darkening would he a wet bias in soil moisture retrievals through a combination of underestimation of soil brightness (at H-pol) and underestimation of vegetation biomass (at V-pol). A new zero-order parameterization was formulated by allowing the volume scattering coefficient to be a function of incidence angle and polarization. The small magnitude of the scattering coefficients allows the zero-order to retain its limited physical significance. Numéro de notice : A2003-350 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/IGARSS.2003.1293767 En ligne : https://doi.org/10.1109/IGARSS.2003.1293767 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26430
in IEEE Transactions on geoscience and remote sensing > vol 41 n° 10 (October 2003) . - pp 2211 - 2223[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-03101 RAB Revue Centre de documentation En réserve L003 Disponible The use of fully polarimetric information for the fuzzy neural classification of SAR images / C.T. Chen in IEEE Transactions on geoscience and remote sensing, vol 41 n° 9 (September 2003)
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Titre : The use of fully polarimetric information for the fuzzy neural classification of SAR images Type de document : Article/Communication Auteurs : C.T. Chen, Auteur ; K.S. Chen, Auteur ; Jong-Sen Lee, Auteur Année de publication : 2003 Article en page(s) : pp 2089 - 2100 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] classification floue
[Termes IGN] classification par réseau neuronal
[Termes IGN] données polarimétriques
[Termes IGN] image AIRSAR
[Termes IGN] matrice de covariance
[Termes IGN] rétrodiffusion
[Termes IGN] utilisation du sol
[Termes IGN] vectorisationRésumé : (Auteur) This paper presents a method, based on a fuzzy neural network, that uses fully polarimetric information for terrain and land-use classification of synthetic aperture radar (SAR) image. The proposed approach makes use of statistical properties of polarimetric data, and takes advantage of a fuzzy neural network. A distance measure, based on a complex Wishart distribution, is applied using the fuzzy c-means clustering algorithm, and the clustering result is then incorporated into the neural network. Instead of preselecting the polarization channels to form a feature vector, all elements of the polarimetric covariance matrix serve as the target feature vector as inputs to the neural network. It is thus expected that the neural network will include fully polarimetric backscattering information for image classification. With the generalization, adaptation, and other capabilities of the neural network, information contained in the covariance matrix, such as the amplitude, the phase difference, the degree of polarization, etc., can be fully explored. A test image, acquired by the Jet Propulsion Laboratory Airborne SAR (AIRSAR) system, is used to demonstrate the advantages of the proposed method. It is shown that the proposed approach can greatly enhance the adaptability and the flexibility giving fully polarimetric SAR for terrain cover classification. The integration of fuzzy c-means (FCM) and fast generalization dynamic learning neural network (DLNN) capabilities makes the proposed algorithm an attractive and alternative method for polarimetric SAR classification. Numéro de notice : A2003-255 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2003.813494 En ligne : https://doi.org/10.1109/TGRS.2003.813494 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22550
in IEEE Transactions on geoscience and remote sensing > vol 41 n° 9 (September 2003) . - pp 2089 - 2100[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-03091 RAB Revue Centre de documentation En réserve L003 Disponible Multitemporal repeat-pass SAR interferometry of boreal forests / J. Askne in IEEE Transactions on geoscience and remote sensing, vol 41 n° 7 (July 2003)PermalinkSAR monitoring of progressive and seasonal ground deformation using the permanent scatterers technique / C. Colesanti in IEEE Transactions on geoscience and remote sensing, vol 41 n° 7 (July 2003)PermalinkRemote sensing techniques to assess water quality / J.C. Ritchie in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 6 (June 2003)PermalinkDéveloppement d'un lidar Raman pour le sondage de la vapeur d'eau et la correction des délais troposphériques en GPS / Olivier Bock in Bulletin d'information scientifique et technique de l'IGN, n° 74 (mars 2003)PermalinkPotential of reflected intensity of airborne laser scanning systems in roadway features identification / Kiyun Yu in Geomatica, vol 56 n° 4 (December 2002)PermalinkThe effect of broadleaf canopies on survey-grade horizontal GPS-GLONASS measurements / Thomas H. Meyer in Surveying and land information systems, vol 62 n° 4 (01/12/2002)PermalinkCalculation of the calibration constant of polarization Lidar and its dependency on atmospheric temperature / Andreas Behrendt in Optics express, vol 10 n° 16 (12/08/2002)PermalinkOn the retrieving of forest stem volume from VHF SAR data: observation and modeling / P. Melon in IEEE Transactions on geoscience and remote sensing, vol 39 n° 11 (November 2001)PermalinkPermalinkTraitement des images de RSO [Radar à Synthèse d'0uverture] / Henri Maître (2001)Permalink