Descripteur
Termes IGN > sciences naturelles > physique > optique > optique physique > radiométrie > rayonnement électromagnétique > diffusion du rayonnement
diffusion du rayonnement |
Documents disponibles dans cette catégorie (190)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
A novel rapid SAR simulator based on equivalent scatterers for three-dimensional forest canopies / Tao Zeng in IEEE Transactions on geoscience and remote sensing, vol 52 n° 9 Tome 1 (September 2014)
[article]
Titre : A novel rapid SAR simulator based on equivalent scatterers for three-dimensional forest canopies Type de document : Article/Communication Auteurs : Tao Zeng, Auteur ; Cheng Hu, Auteur ; Hanwei Sun, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 5243 - 5255 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] canopée
[Termes IGN] image radar
[Termes IGN] modèle de diffusion du rayonnement
[Termes IGN] rétrodiffusion
[Termes IGN] simulation 3D
[Termes IGN] traitement du signalRésumé : (Auteur) Synthetic aperture radar (SAR) simulation of 3-D forest canopies is a powerful tool for studying the interaction between radar and forest, for testing new applications, and for devising inversion algorithms of forest structures. SAR raw-signal generation is frequently used in point-target simulation but is rarely used in 3-D forest simulation. The existing simulators directly produce SAR images based on an impulse response function (IRF) without involving raw-signal generation and various nonideal factors. In this paper, a novel simulator to produce SAR images of 3-D forest canopies is proposed. It incorporates a SAR raw-signal generation process taking account of various nonideal factors such as trajectory deviation of radar platforms and complexity of natural environments, which is more faithful to realistic remote sensing systems. Furthermore, an approach to speed up the raw-signal generation is put forward based on the equivalent scattering model consisting of a few virtual scatterers with specially calculated positions and backscattering matrices. Thus, the raw signals received from the entire forest canopy can be equivalent to those from virtual scatterers in the case of tiny slant-range errors. The error sensitivity of equivalent conditions is analyzed, and the optimum selection of equivalent parameters is derived considering the compromise between precision and efficiency. The results of simulation and forest height inversion demonstrate the feasibility and potential utilities of the proposed simulator. Numéro de notice : A2014-438 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2287691 En ligne : https://doi.org/10.1109/TGRS.2013.2287691 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=73975
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 9 Tome 1 (September 2014) . - pp 5243 - 5255[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 065-2014091A RAB Revue Centre de documentation En réserve L003 Disponible Backscattering of individual LiDAR pulses from forest canopies explained by photogrammetrically derived vegetation structure / Ilkka Korpela in ISPRS Journal of photogrammetry and remote sensing, vol 83 (September 2013)
[article]
Titre : Backscattering of individual LiDAR pulses from forest canopies explained by photogrammetrically derived vegetation structure Type de document : Article/Communication Auteurs : Ilkka Korpela, Auteur ; Aarne Hovi, Auteur ; Lauri Korhonen, Auteur Année de publication : 2013 Article en page(s) : pp 81 - 93 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] appariement de lignes
[Termes IGN] canopée
[Termes IGN] diffusion du rayonnement
[Termes IGN] forêt
[Termes IGN] impulsion laser
[Termes IGN] photogrammétrie métrologique
[Termes IGN] photogrammétrie terrestre
[Termes IGN] rétrodiffusion
[Termes IGN] signal lidarRésumé : (Auteur) In recent years, airborne LiDAR sensors have shown remarkable performance in the mapping of forest vegetation. This experimental study looks at LiDAR data at the scale of individual pulses to elucidate the sources behind interpulse variation in backscattering. Close-range photogrammetry was used for obtaining the canopy reference measurements at the ratio scale. The experiments illustrated different orientation techniques in the field, LiDAR acquisitions and photogrammetry in both leaf-on and leaf-off conditions, and two-waveform recording LiDAR sensors. The intrafootprint branch silhouettes in zenith-looking images, in which the camera, footprint, and LiDAR sensor were collinear, were extracted and contrasted with LiDAR backscattering. An enhanced planimetric match (refinement of strip matching) was achieved by shifting the pulses in a strip and searching for the maximal correlation between the silhouette and LiDAR intensity. The relative silhouette explained up to 80–90% of the interpulse variation. We tested whether accounting for the Gaussian spread of intrafootprint irradiance would improve the correlations, but the effect was blurred by small-scale geometric noise. Accounting for receiver gain variations in the Leica ALS60 sensor data strengthened the dependences. The size of the vegetation objects required for triggering a LiDAR observation was analyzed. We demonstrated the use of LiDAR pulses adjacent to canopy vegetation, which did not trigger a canopy echo, for canopy mapping. Pulses not triggering an echo constitute the complement to the actual canopy. We conclude that field photogrammetry is a useful tool for mapping forest canopies from below and that quantitative analysis is feasible even at the scale of single pulses for enhanced understanding of LiDAR observations from vegetation. Numéro de notice : A2013-489 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.06.002 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.06.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32627
in ISPRS Journal of photogrammetry and remote sensing > vol 83 (September 2013) . - pp 81 - 93[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 081-2013091 RAB Revue Centre de documentation En réserve L003 Disponible Retrieval of tropical forest biomass information from ALOS PALSAR data / Mahmudur Rahman in Geocarto international, vol 28 n° 5-6 (August - October 2013)
[article]
Titre : Retrieval of tropical forest biomass information from ALOS PALSAR data Type de document : Article/Communication Auteurs : Mahmudur Rahman, Auteur ; Josaphat Tetuko Sri Sumantyo, Auteur Année de publication : 2013 Article en page(s) : pp 382 - 403 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande L
[Termes IGN] Bangladesh
[Termes IGN] biomasse
[Termes IGN] forêt tropicale
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image radar moirée
[Termes IGN] régression
[Termes IGN] rétrodiffusionRésumé : (Auteur) Advanced Land Observing Satellite Phased Array L-band Synthetic Aperture Radar (ALOS PALSAR) data from different observation modes were analysed to determine (1) which observation mode most accurately retrieves tropical forest biomass information and (2) whether different modes, when considered together, yield improved results in comparison to identical data-sets analysed independently. We performed regression analysis to estimate above-ground forest biomass using PALSAR backscatter data for natural and planted forests in south-eastern Bangladesh. The coefficient of determination (r 2) was lower or equal to 0.499 (n = 70) when PALSAR data from different observation modes were separately considered, but increased sharply when one class (rubber) is dropped and average backscatter of fine beam single (FBS) and polarimetric (PLR) modes are used in the analysis. The results presented in this article are useful for both regional and global forest biomass inventories and fixing acquisition modes for planned L-band SAR missions. Numéro de notice : A2013-547 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2012.710652 Date de publication en ligne : 04/09/2012 En ligne : https://doi.org/10.1080/10106049.2012.710652 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32683
in Geocarto international > vol 28 n° 5-6 (August - October 2013) . - pp 382 - 403[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 059-2013031 RAB Revue Centre de documentation En réserve L003 Disponible Polarization scatterer feature metric space / William L. Cameron in IEEE Transactions on geoscience and remote sensing, vol 51 n° 6 Tome 2 (June 2013)
[article]
Titre : Polarization scatterer feature metric space Type de document : Article/Communication Auteurs : William L. Cameron, Auteur ; Houra Rais, Auteur Année de publication : 2013 Article en page(s) : pp 3638 - 3647 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] coin réflecteur
[Termes IGN] diffusion du rayonnement
[Termes IGN] diffusométrie
[Termes IGN] polarisationRésumé : (Auteur) This paper extends prior work by Cameron and Rais to define new multidimensional representations of the reciprocal scatterer space and the general polarization scatterer space, including distance metric definitions for these representations. The relationship between the maximum symmetric scatterer type and the maximum value that can be attained by the asymmetry parameter is derived to determine the shape of the polarization reciprocal scatterer space. Moreover, a metric is derived for this space that reduces to the symmetric scatterer space metric when the asymmetry parameter is zero. These results are extended to the general polarization scatterer space by defining a metric on the polarization scatterer space that reduces to the polarization reciprocal scatterer metric when the reciprocity parameter Ørec is zero Numéro de notice : A2013-302 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2221466 En ligne : https://doi.org/ 10.1109/TGRS.2012.2221466 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32440
in IEEE Transactions on geoscience and remote sensing > vol 51 n° 6 Tome 2 (June 2013) . - pp 3638 - 3647[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 065-2013061B RAB Revue Centre de documentation En réserve L003 Disponible Soil moisture estimation under low vegetation cover using a multi-angular polarimetric decomposition / Thomas Jaghuber in IEEE Transactions on geoscience and remote sensing, vol 51 n° 4 Tome 2 (April 2013)
[article]
Titre : Soil moisture estimation under low vegetation cover using a multi-angular polarimetric decomposition Type de document : Article/Communication Auteurs : Thomas Jaghuber, Auteur ; Irena Hajnsek, Auteur ; Axel Bronstert, Auteur ; Konstantinos Panagiotis Papathanassiou, Auteur Année de publication : 2013 Article en page(s) : pp 2201 - 2215 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande L
[Termes IGN] couvert végétal
[Termes IGN] décomposition d'image
[Termes IGN] diffusion du rayonnement
[Termes IGN] humidité du sol
[Termes IGN] image E-SAR
[Termes IGN] image radar moirée
[Termes IGN] polarimétrie radar
[Termes IGN] rétrodiffusion
[Termes IGN] surface cultivéeRésumé : (Auteur) The estimation of volumetric soil moisture under low agricultural vegetation from fully polarimetric synthetic aperture radar (SAR) data at L-band using a multi-angular polarimetric decomposition is investigated. Radar polarimetry provides the framework to decompose the backscattered signal into different canonical scattering mechanisms referring to scattering contributions from the underlying soil and the vegetation cover. Multi-angular observation diversity further increases the information space for soil moisture inversion enabling higher inversion rates and a stable inversion performance. The developed approach was applied on the multi-angular L-band data set acquired by German Aerospace Center's ESAR sensor as part of the OPAQUE campaign in 2008. The obtained results are compared against ground measurements collected by the OPAQUE team over a variety of vegetated agricultural fields. The validation of the estimated against ground measured soil moisture results in an root mean square error level of 6–8 vol.% including all test fields with a variety of crop types. Numéro de notice : A2013-222 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2209433 En ligne : https://doi.org/10.1109/TGRS.2012.2209433 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32360
in IEEE Transactions on geoscience and remote sensing > vol 51 n° 4 Tome 2 (April 2013) . - pp 2201 - 2215[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 065-2013041B RAB Revue Centre de documentation En réserve L003 Disponible A proposed framework to unmix scattering mechanisms of polarimetric radar images using very high resolution optical images / Sébastien Giordano in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol I-7 (2012)PermalinkTesting a near-infrared Lidar mounted with a large incidence angle to monitor the water level of turbid reservoirs / S. Tamari in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 6 supplement (December 2011)PermalinkRadar backscatter mapping using TerraSAR-X / P. Rizzoli in IEEE Transactions on geoscience and remote sensing, vol 49 n° 10 Tome 1 (October 2011)PermalinkEffect of corn on C-an L-band radar backscatter: a correction method for soil moisture retrieval / A. Joseph in Remote sensing of environment, vol 114 n° 11 (15/11/2010)PermalinkFriendly reflections: monitoring water level with GNSS / A. Egido in GPS world, vol 21 n° 9 (September 2010)PermalinkSnow permitivity retrieval inversion algorithm for estimating snow wetness / G. Singh in Geocarto international, vol 25 n° 3 (June 2010)PermalinkA case study of using Raman lidar measurements in high-accuracy GPS applications / Pierre Bosser in Journal of geodesy, vol 84 n° 4 (April 2010)PermalinkDiscrimination of agricultural crops in a tropical semi-arid region of Brazil based on L-band polarimetric airborne SAR data / W. Silva in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)PermalinkPotentiality of feed-forward neural networks for classifying dark formations to oil spills and look-alikes / Konstantinos Topouzelis in Geocarto international, vol 24 n° 3 (June - July 2009)PermalinkRadiometric Calibration of LIDAR Intensity With Commercially Available Reference Targets / S. Kaasalainen in IEEE Transactions on geoscience and remote sensing, vol 47 n° 2 (February 2009)Permalink