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Sea ice monitoring by L-band SAR: an assessment based on literature and comparisons of JERS-1 and ERS-1 imagery / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 44 n° 4 (April 2006)
[article]
Titre : Sea ice monitoring by L-band SAR: an assessment based on literature and comparisons of JERS-1 and ERS-1 imagery Type de document : Article/Communication Auteurs : W. Dierking, Auteur ; T. Busche, Auteur Année de publication : 2006 Article en page(s) : pp 957 - 970 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] angle d'incidence
[Termes IGN] Arctique
[Termes IGN] bande L
[Termes IGN] diffusomètre
[Termes IGN] glace de mer
[Termes IGN] Groenland
[Termes IGN] image ERS-SAR
[Termes IGN] image JERS
[Termes IGN] polarisation
[Termes IGN] surveillance hydrologique
[Termes IGN] Svalbard
[Termes IGN] zone polaireRésumé : (Auteur) Spaceborne single-polarization C-band synthetic aperture radar (SAR) imagery is widely used to gather information about the state of the sea ice cover in the polar regions. C-band is regarded as a reasonable choice for all-season monitoring capabilities. For specific mapping tasks, however, other frequency hands can be more suitable. In the first part of this paper, the summary of a literature study dealing with the utilization of L-band SAR imagery for sea ice monitoring is presented. Investigations reveal that if deformation features such as ice ridges, rubble fields, and brash ice are to be mapped, L-band radar is superior in a number of cases. The second part of this paper addresses the comparison of JERS-1 and ERS-1 SAR images that were acquired over sea ice east of Svalbard and along the east coast of Greenland. The effects of the different frequencies, polarizations, and incidence angles of the two SAR Systems are discussed. It is demonstrated that the images of both sensors complement one another in the analysis of ice conditions, resulting in a more detailed view of the sea ice cover state. Copyright IEEE Numéro de notice : A2006-211 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2005.861745 En ligne : https://doi.org/10.1109/TGRS.2005.861745 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27938
in IEEE Transactions on geoscience and remote sensing > vol 44 n° 4 (April 2006) . - pp 957 - 970[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-06041 RAB Revue Centre de documentation En réserve L003 Disponible Utilizing calibrated GPS reflected signals to estimate soil reflectivity and dielectric constant: results from SMEX02 / S.J. Katzberg in Remote sensing of environment, vol 100 n° 1 (15/01/2006)
[article]
Titre : Utilizing calibrated GPS reflected signals to estimate soil reflectivity and dielectric constant: results from SMEX02 Type de document : Article/Communication Auteurs : S.J. Katzberg, Auteur ; O. Torres, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 17 - 28 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] bande L
[Termes IGN] constante diélectrique
[Termes IGN] données de terrain
[Termes IGN] étalonnage géométrique
[Termes IGN] humidité du sol
[Termes IGN] Iowa (Etats-Unis)
[Termes IGN] réflectance de surface
[Termes IGN] réflectivité
[Termes IGN] réflexion spéculaire
[Termes IGN] signal GPS
[Termes IGN] Soil Moisture Experiment
[Termes IGN] sol arable
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) Extensive reflected GPS data was collected using a GPS reflectometer installed on an HC130 aircraft during the Soil Moisture Experiment 2002 (SMEX02) near Ames, Iowa. At the same time, widespread surface truth data was acquired in the form of point soil moisture profiles, areal sampling of near-surface soil moisture, total green biomass and precipitation history, among others. Previously, there have been no reported efforts to calibrate reflected GPS data sets acquired over land. This paper reports the results of two approaches to calibration of the data that yield consistent results. It is shown that estimating the strength of the reflected signals by either (1) assuming an approximately specular surface reflection or (2) inferring the surface slope probability density and associated normalization constants give essentially the saine results for the conditions encountered in SMEX02. The corrected data is converted to surface reflectivity and then to dielectric constant as a test of the calibration approaches. Utilizing the extensive in-situ soil moisture related data, this paper also presents the results of comparing the GPS-inferred relative dielectric constant with the Wang - Schmugge model frequently used to relate volume moisture content to dielectric constant. It is shown that the calibrated GPS reflectivity estimates follow the expected dependence of permittivity with volume moisture, but with the following qualification: The soil moisture value governing the reflectivity appears to come from only the top 1 - 2 cm of soil, a result consistent with results found for other microwave techniques operating at L-band. Nevertheless, the experimentally derived dielectric constant is generally lower than predicted. Possible explanations are presented to explain this result. Numéro de notice : A2006-014 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2005.09.015 En ligne : https://doi.org/10.1016/j.rse.2005.09.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27741
in Remote sensing of environment > vol 100 n° 1 (15/01/2006) . - pp 17 - 28[article]Relating SAR image texture to the biomass of regenerating tropical forests / T.M. Kuplich in International Journal of Remote Sensing IJRS, vol 26 n° 21 (November 2005)
[article]
Titre : Relating SAR image texture to the biomass of regenerating tropical forests Type de document : Article/Communication Auteurs : T.M. Kuplich, Auteur ; P.J. Curran, Auteur ; P.M. Atkinson, Auteur Année de publication : 2005 Article en page(s) : pp 4829 - 4854 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande L
[Termes IGN] canopée
[Termes IGN] forêt tropicale
[Termes IGN] image JERS
[Termes IGN] image radar
[Termes IGN] Manaus
[Termes IGN] masse végétale
[Termes IGN] niveau de gris (image)
[Termes IGN] teneur en carbone
[Termes IGN] texture d'image
[Termes IGN] variogrammeRésumé : (Auteur) An accurate global carbon budget requires information on terrestrial carbon sink strength. Regenerating tropical forests are known to be important terrestrial carbon sinks but information on their location, extent and biomass (from which carbon content can be estimated) is incomplete. The use of remotely sensed data in optical wavelengths has been of limited use due to both the weak relationship between optical radiation and forest biomass and near-constant cloud cover in the tropics. L-band Synthetic Aperture Radar (SAR) backscatter, however, is related positively to biomass (but only up to an asymptote of around 40-90T ha-1) and can be obtained independently of cloud cover. Both canopy structure and biomass change over time as pioneer species are replaced by early and late regenerating species. These structural changes are related to an increase in (i) tree height, (ii) tree species richness and (iii) canopy thickness and influence the roughness of the canopy surface and consequently SAR image texture. Therefore, we investigated the degree to which textural information could be used to increase the correlation between image tone (backscatter) and biomass. Field data were used to estimate the biomass of 37 regenerating forests plots in Brazilian Amazonia. Texture measures derived from local statistics, the grey level co-occurrence matrix (GLCM) and the variogram were evaluated using simulated images on the basis of their ability to identify significant differences in image texture independently of image contrast. The selected texture measures were applied to L-band JERS-1 (Japanese Earth Resources Satellite) SAR images and the correlation between backscatter and biomass was determined for regenerating tropical forests. A strong correlation was found for the texture measures and biomass. The ra2 (adjusted coefficient of determination), measuring the correlation between backscatter and biomass, increased from 0.74 to 0.82 with the addition of GLCM-derived contrast. The addition of image texture (GLCM-derived contrast) to image tone (backscatter) potentially increases the accuracy with which JERS-1 SAR data can be used to estimate biomass in tropical forests. Numéro de notice : A2005-469 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500239107 En ligne : https://doi.org/10.1080/01431160500239107 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27605
in International Journal of Remote Sensing IJRS > vol 26 n° 21 (November 2005) . - pp 4829 - 4854[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-05211 RAB Revue Centre de documentation En réserve L003 Disponible The emissivity of foam-covered water surface at L-band: theoretical modelling and experimental results from the frog 2003 field experiment / A. Camps in IEEE Transactions on geoscience and remote sensing, vol 43 n° 5 (May 2005)
[article]
Titre : The emissivity of foam-covered water surface at L-band: theoretical modelling and experimental results from the frog 2003 field experiment Type de document : Article/Communication Auteurs : A. Camps, Auteur ; M. Vall-Llossera, Auteur ; R. Villarino, Auteur Année de publication : 2005 Article en page(s) : pp 925 - 937 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] angle d'incidence
[Termes IGN] bande L
[Termes IGN] emissivité
[Termes IGN] houle
[Termes IGN] polarisation
[Termes IGN] salinité
[Termes IGN] spectre électromagnétique
[Termes IGN] surface de la mer
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) Sea surface salinity can he measured by microwave radiometry at L-band (1400-1427 MHz). This frequency is a compromise between sensitivity to the salinity, small atmospheric perturbation, and reasonable pixel resolution. The description of the ocean emission depends on two main factors: 1) the sea water permittivity, which is a function of salinity, temperature, and frequency, and 2) the sea surface state, which depends on the wind-induced wave spectrum, swell, and rain-induced roughness spectrum, and by the foam coverage and its emissivity. This study presents a simplified two-layer emission model for foam-covered water and the results of a controlled experiment to measure the foam emissivity as a function of salinity, foam thickness, incidence angle, and polarization. Experimental results are presented, and then compared to the two-layer foam emission model with the measured foam parameters used as input model parameters. At 37 psu salt water the foam-induced emissivity increase is ~0.007 per millimeter of foam thickness (extrapolated to nadir), increasing with increasing incidence angles at vertical polarization, and decreasing with increasing incidence angles at horizontal polarization. Numéro de notice : A2005-213 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2004.839651 En ligne : https://doi.org/10.1109/TGRS.2004.839651 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27350
in IEEE Transactions on geoscience and remote sensing > vol 43 n° 5 (May 2005) . - pp 925 - 937[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-05051 RAB Revue Centre de documentation En réserve L003 Disponible Spatial resolution and processing tradeoffs for HYDROS: application of reconstruction and resolution enhancement techniques / David G. Long in IEEE Transactions on geoscience and remote sensing, vol 43 n° 1 (January 2005)
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Titre : Spatial resolution and processing tradeoffs for HYDROS: application of reconstruction and resolution enhancement techniques Type de document : Article/Communication Auteurs : David G. Long, Auteur Année de publication : 2005 Article en page(s) : pp 3 - 12 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] accentuation d'image
[Termes IGN] bande L
[Termes IGN] capteur (télédétection)
[Termes IGN] humidité du sol
[Termes IGN] HYDROS
[Termes IGN] Hydrospheric State
[Termes IGN] image à basse résolution
[Termes IGN] mission spatiale
[Termes IGN] radiomètre à hyperfréquence
[Termes IGN] reconstruction d'imageRésumé : (Auteur) Recent developments in reconstruction and resolution enhancement for microwave instruments suggest a possible tradeoff between computation, resolution, and downlink data rate based on postcollection reconstruction/resolution enhancement processing. The Hydrospheric State mission is designed to measure global soil moisture and freeze/thaw state in support of weather and climate prediction, water, energy, and carbon cycle studies, and natural hazards monitoring. It will use an active and passive L-band microwave system that optimizes measurement accuracy, spatial resolution, and coverage. The active channels use synthetic aperture radar-type processing to achieve fine spatial resolution, requiring a relatively high downlink data rate and ground processor complexity. To support real-time applications and processing, an optional postcollection reconstruction and resolution enhancement method is investigated. With this option, much lower rate real-aperture radar data are used along with ground-based postprocessing algorithms to enhance the resolution of the observations to achieve the desired 10-km resolution. Several approaches are investigated in this paper. It is determined that a reconstruction/resolution enhancement technique combining both forward- and aft-looking measurements enables estimation of 10-km resolution or better backscatter values at acceptable accuracy. Key tradeoffs to achieve this goal are considered. Numéro de notice : A2005-057 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2004.838385 En ligne : https://doi.org/10.1109/TGRS.2004.838385 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27195
in IEEE Transactions on geoscience and remote sensing > vol 43 n° 1 (January 2005) . - pp 3 - 12[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-05011 RAB Revue Centre de documentation En réserve L003 Disponible Retrieval of soil moisture from passive and active L/S band sensor (PALS) observations during the soil moisture experiment in 2002 (SMEX) / U. Narayan in Remote sensing of environment, vol 92 n° 4 (30 September 2004)PermalinkA phase signature for detecting wet subsurface structures using polarimetric L-band SAR / Y. Lasne in IEEE Transactions on geoscience and remote sensing, vol 42 n° 8 (August 2004)PermalinkThe EuroSTARRS airborne campaign in support of the SMOS mission: first results over land surfaces / K. Saleh in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)PermalinkThe coregistration, calibration, and interpretation of multiseason JERS-1 SAR data over South America / Paul Siqueira in Remote sensing of environment, vol 87 n° 4 (15/11/2003)PermalinkFully polarimetric airborne SAR and ERS SAR observations of snow: implications for selection of Envisat ASAR modes / T. Guneriussen in International Journal of Remote Sensing IJRS, vol 24 n° 19 (October 2003)PermalinkPolarimetric SAR speckle noise model / C. Lopez-Martinez in IEEE Transactions on geoscience and remote sensing, vol 41 n° 10 (October 2003)PermalinkSpeckle filtering and coherence estimation of polarimetric SAR interferometry data for forest applications / Jong-Sen Lee in IEEE Transactions on geoscience and remote sensing, vol 41 n° 10 (October 2003)PermalinkSurface soil moisture retrieval from L-band radiometry: a global regression study / T. Pellarin in IEEE Transactions on geoscience and remote sensing, vol 41 n° 9 (September 2003)PermalinkJers SAR interferometry for land subsidence monitoring / Tazio Strozzi in IEEE Transactions on geoscience and remote sensing, vol 41 n° 7 (July 2003)PermalinkMultitemporal repeat-pass SAR interferometry of boreal forests / J. Askne in IEEE Transactions on geoscience and remote sensing, vol 41 n° 7 (July 2003)Permalink