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Radar based classification prior to biomass retrieval from P-Band SAR data / Pierre-Louis Frison (2016)
Titre : Radar based classification prior to biomass retrieval from P-Band SAR data Type de document : Article/Communication Auteurs : Pierre-Louis Frison , Auteur ; Ludovic Villard, Auteur ; Thierry Koleck, Auteur ; Thuy Le Toan, Auteur Editeur : Paris : Agence Spatiale Européenne ASE / European Space Agency ESA Année de publication : 2016 Conférence : LPS 2016, ESA Living Planet Symposium 09/05/2016 13/05/2016 Prague République tchèque programme sans actes Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] bande P
[Termes IGN] Biomass
[Termes IGN] biomasse aérienne
[Termes IGN] détection de changement
[Termes IGN] données polarimétriques
[Termes IGN] forêt boréale
[Termes IGN] forêt tropicale
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-SARRésumé : (auteur) SAR data are well suited for the retrieval of biomass from vegetated areas. In particular, the ability of low frequencies to deeply penetrate dense vegetation, allows P band radar data to retrieve high biomass levels that can be encountered over forests, where other frequencies show their limitations. The BIOMASS mission, consisting in the launch of a P band SAR sensor, has been selected by ESA as the 7th Earth Explorer mission, will allow to estimate the world’s forest biomass and its changes. However, forests observe strong spatial differences in terms of structure or surface topography. These differences induce significant changes of the scattering mechanism occurring within a resolution cell. At global scale, the differences are obvious (for example between boreal and tropical regions), but at regional scale, strong differences can also be observed (for example gallery forests within savannahs, forest edges, or changes due to surface topography). The consideration of these changes is a major issue to improve the robustness of the inversion algorithm in order to reduce the errors of the biomass estimations. Up to now, no unique inversion method has been developed, that would be valid over the wide variety of forests types. An alternative is to propose a classification method that will allow to discriminate between forest types in terms of radar scattering behavior in order to apply the best suited algorithm. This is the aim of the present study. The focus is put on the analysis of the different polarimetric indices that can be derived from the fully polarimetric data acquired during the BIOMASS mission. Then the contribution of other data that should be concomitant to the BIOMASS mission, such as Sentinel-1 at C band or PALSAR2 at L band will also be investigated. This study will be based on the analysis of P band SAR data acquired during airborne campaigns other boreal (BioSAR 1 and 2) and tropical (TropiSAR, AfriSAR) forests, over a wide range of biomass value and terrain conditions. Numéro de notice : C2016-056 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : FORET/IMAGERIE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans En ligne : http://lps16.esa.int/page_session187.php#2131p Format de la ressource électronique : URL abstract Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91908 Towards a system combining SAR and optical Sentinel data to monitor gold mining in the Guiana shield / Mathieu Rahm (2016)
Titre : Towards a system combining SAR and optical Sentinel data to monitor gold mining in the Guiana shield Type de document : Article/Communication Auteurs : Mathieu Rahm, Auteur ; Cédric Lardeux, Auteur ; Pierre-Louis Frison , Auteur ; et al., Auteur Editeur : Paris : Agence Spatiale Européenne ASE / European Space Agency ESA Année de publication : 2016 Conférence : LPS 2016, ESA Living Planet Symposium 09/05/2016 13/05/2016 Prague République tchèque programme sans actes Importance : 60 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] Brésil
[Termes IGN] déboisement
[Termes IGN] fusion d'images
[Termes IGN] Guyana
[Termes IGN] Guyane (département français)
[Termes IGN] image Sentinel-MSI
[Termes IGN] image Sentinel-SAR
[Termes IGN] mine d'or
[Termes IGN] pollution des eaux
[Termes IGN] SurinameRésumé : (auteur) Included in the larger Guiana Shield ecosystem, Suriname, Guyana, French Guiana and the Brazilian state of Amapá possess one of the largest continuous tracts of pristine forest in the world. Under little threat until fifteen years ago, deforestation and forest degradation are of increasing concern in the region. Gold mining activities driven by the sustained increase of gold price has experienced a significant boom and represents nowadays one of the main driver. The pollution of rivers and streams by mercury used in small-scale gold mining is also expanding, which increases risks to local population health and freshwater biodiversity. In 2010, the French National Forest Office (ONF) showed by using optical satellite images at medium and high resolution (HR) that gold mining activities’ impacts on forest cover and freshwater increased approximately by a factor three in the region between 2001 and 2008. More recently, Alvarez-Berríos et al. (2015) pointed out a sustained acceleration of deforestation caused by gold mining in the Guiana shield between 2007 and 2013. However, this study which was performed using low resolution data at the scale of South America has limited capacity to detect gold mining, especially in the high forest cover of Guiana Shield where small- and medium-scale operations account for most of the deforestation. To overcome this limitation, the REDD+ for the Guiana Shield project conducted a study co-funded by WWF Guianas to update for 2014 the ONF 2001-2008 results, using optical multi-sensors data at medium and high resolution. The study was carried out following a unique collaborative and participatory approach involving a team of experts from the forestry and environmental services of each territory, namely SEMA (Amapá-Brazil), ONF (French Guiana-France), GFC (Guyana), and SBB (Suriname). The results confirmed the rapid expansion of the activity in the region where more than 92,000 ha were newly deforested between 2008 and 2014, compared to approximately 46,000 ha during the period 2001-2008. In 2014, more than 9,000 km of waterways were in direct contact with mining sites, which is approximately 6.5 times more than in 2001. Although a reliable, accurate and robust regional methodology has been developed and operationally implemented, the frequent and widespread cloud cover of the Guianan moist forest region represents a challenge for the use of optical HR data. The need to process time series of satellite images in most areas to reduce cloud cover is time-consuming. Despite processing more than two hundreds images, 3.6% of the study area remained masked by clouds. The recent free access to SAR HR Sentinel-1 data offers great opportunities to improve the process. SAR sensors can peer through clouds and their sensitivity to soil moisture can help to better detect small-scale mining sites. Therefore, the REDD+ for the Guiana Shield project has started to build capacities in the region on SAR image interpretation and processing using the Sentinel Application Platform (SNAP). A first mosaic of Sentinel-1 data covering Suriname, Guyana, French Guiana and the Brazilian state of Amapá has been created and automated pre-processing steps have been developed. The integration of Sentinel-1 data in the regional gold mining monitoring system has been successfully tested in four study sites, one in each country. The coming free access to optical HR Sentinel-2 data opens even more perspectives towards the development of cost-effective monitoring systems in the region, especially valuable in the context of REDD+. This paper first presents the results of the impact of gold mining activities on the forest cover and freshwater for 2014 and shows the evolution since 2001. Secondly, it provides the first outcomes towards the development of time- and cost-efficient forest monitoring systems in the region. Numéro de notice : C2016-058 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : http://lps16.esa.int/page_session187.php#1306p Format de la ressource électronique : URL abstract Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91912 Documents numériques
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Towards a System Combining SAR... (final report) - pdf auteurAdobe Acrobat PDF Temporal decorrelation in L-, C-, and X-band satellite radar interferometry for pasture on drained cs / Yu Morishita in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)
[article]
Titre : Temporal decorrelation in L-, C-, and X-band satellite radar interferometry for pasture on drained cs Type de document : Article/Communication Auteurs : Yu Morishita, Auteur ; Ramon F. Hanssen, Auteur Année de publication : 2015 Article en page(s) : pp 1096 - 1104 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] bande X
[Termes IGN] décorrélation
[Termes IGN] humidité du sol
[Termes IGN] image ALOS
[Termes IGN] image Sentinel-SAR
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] paturage
[Termes IGN] tourbe
[Termes IGN] traitement d'image radar
[Termes IGN] zone ruraleRésumé : (Auteur) Temporal decorrelation is one of the main limitations of synthetic aperture radar (SAR) interferometry. For nonurban areas, its mechanism is very complex, as it is very dependent of vegetation types and their temporal dynamics, actual land use, soil types, and climatological circumstances. Yet, an a priori assessment and comprehension of the expected coherence levels of interferograms are required for designing new satellite missions (in terms of frequency, resolution, and repeat orbits), for choosing the optimal data sets for a specific application, and for feasibility studies for new interferometric applications. Although generic models for temporal decorrelation have been proposed, their parameters depend heavily on the land use in the area of interest. Here, we report the behavior of temporal decorrelation for a specific class of land use: pasture on drained peat soils. We use L-, C-, and X-band SAR observations from the Advanced Land Observation Satellite (ALOS), European Remote Sensing Satellite, Envisat, RADARSAT-2, and TerraSAR-X missions. We present a dedicated temporal decorrelation model using three parameters and demonstrate how coherent information can be retrieved as a function of frequency, repeat intervals, and coherence estimation window sizes. New satellites such as Sentinel-1 and ALOS-2, with shorter repeat intervals than their predecessors, would enhance the possibility to obtain a coherent signal over pasture. Numéro de notice : A2015-109 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2333814 En ligne : https://doi.org/10.1109/TGRS.2014.2333814 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75627
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 2 (February 2015) . - pp 1096 - 1104[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Advanced differential interferometry synthetic aperture radar techniques for deformation monitoring: a review on sensors and recent research development / O. Idrees Mohammed in Geocarto international, vol 29 n° 5 - 6 (August - October 2014)
[article]
Titre : Advanced differential interferometry synthetic aperture radar techniques for deformation monitoring: a review on sensors and recent research development Type de document : Article/Communication Auteurs : O. Idrees Mohammed, Auteur ; Vahideh Saeidi, Auteur ; Biswajeet Pradhan, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 536-553 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse comparative
[Termes IGN] bande P
[Termes IGN] bande X
[Termes IGN] coin réflecteur
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image Sentinel-SAR
[Termes IGN] interferométrie différentielle
[Termes IGN] interféromètrie par radar à antenne synthétiqueRésumé : (auteur) This paper reviews the advanced differential interferometry synthetic aperture radar (A-DInSAR) techniques, with two major components in focus. First is the basic concepts, synthetic aperture radar (SAR) data sources and the different algorithms documented in the literature, primarily focusing on persistent scatterers. In the second part, the techniques are compared in order to establish more linkage in terms of the variability of their applications, strength and validation of the interpreted results. Also, current issues in sensor and algorithm development are discussed. The study identified six existing A-DInSAR algorithms used for monitoring various deformation types. Generally, reports of their performance indicate that all the techniques are capable of measuring deformation phenomena at varying spatial resolution with high level of accuracy. However, their usability in suburban and vegetated areas yields poor results, compared to urbanized areas, due to inadequate permanent features that could provide sufficient coherent point targets. Meanwhile, there is continuous development in sensors and algorithms to expand the applicability domain of the technology for a wide range of deformable surfaces and displacement patterns with higher precision. On the sensor side, most of the latest SAR sensors employ longer wavelength (X and P bands) to increase the penetrating power of the signal and two other sensors (ALOS-2 PALSA-2 and SENTINEL-1) are scheduled to be launched in 2013. Researchers are investigating the possibility of using single-pass sensors with different look angles for SAR data collection. With these, it is expected that more data will be available for various applications. Algorithms such as corner reflector interferometry SAR, along track interferometry, liqui-InSAR, and squeeSAR are emerging to increase reliable estimation of deformation from different surfaces. Numéro de notice : A2014-411 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2013.807305 En ligne : http://www.tandfonline.com/doi/full/10.1080/10106049.2013.807305 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=73948
in Geocarto international > vol 29 n° 5 - 6 (August - October 2014) . - pp 536-553[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2014031 RAB Revue Centre de documentation En réserve L003 Disponible