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Estimating accuracy in optimal deconvolution of synthetic AMSR-E observations / A.S. Limaye in Remote sensing of environment, vol 100 n° 1 (15/01/2006)  

Public [article]  inRemote sensing of environment > vol 100 n° 1 (15/01/2006) . - pp 133 - 142 Titre : Estimating accuracy in optimal deconvolution of synthetic AMSR-E observations Type de document : Article/Communication Auteurs : A.S. Limaye, Auteur ; William L. Crosson, Auteur ; C.A. Laymon, Auteur Année de publication : 2006 Article en page(s) : pp 133 - 142 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] déconvolution [Termes IGN] eau de surface [Termes IGN] image Aqua-AMSR [Termes IGN] télédétection en hyperfréquence [Termes IGN] température de luminance Résumé : (Auteur) Optimal deconvolution (ODC) utilizes the footprint overlap in microwave observations to estimate the earth's brightness temperatures (TB ). This paper examines the accuracy of ODC estimated TB compared with a standard averaging technique. Because brightness temperatures cannot be independently verified, we constructed synthetic True TB for accuracy assessment. We assigned TB at a high spatial resolution (1 km) grid and computed the True TB by spatial averaging of the assigned TB to a lower resolution earth grid (25 km), selected to match the resolution of products generated from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSRE). We used the sensor antenna response function along with the 1km assigned TB to generate synthetic observations at AMSRE footprint locations. These synthetic observations were subsequently deconvolved in the ODC technique to estimate TB at the lower resolution earth grid. The ODC estimated TB and the simple grid cell averages of the synthetic observations were compared with the True TB allowing us to quantify the efficacy of each technique. In areas of high TB contrast (such as boundaries of water bodies), ODC performed significantly better than averaging. In other areas, ODC and averaging techniques produced similar results. A technique similar to ODC can be effective in delineating water bodies with significant clarity. That will allow microwave observations to be utilized near the shorelines, a trouble spot for the currently used averaging techniques. Numéro de notice : A2006-015 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2005.10.008 En ligne : https://doi.org/10.1016/j.rse.2005.10.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27742 [article]

Land cover-based optimal deconvolution of PALS L-band microwave brightness temperatures / A.S. Limaye in Remote sensing of environment, vol 92 n° 4 (30 September 2004)  

Public [article]  inRemote sensing of environment > vol 92 n° 4 (30 September 2004) . - pp 497 - 506 Titre : Land cover-based optimal deconvolution of PALS L-band microwave brightness temperatures Type de document : Article/Communication Auteurs : A.S. Limaye, Auteur ; William L. Crosson, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 497 - 506 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] agriculture [Termes IGN] biomasse [Termes IGN] capteur actif [Termes IGN] capteur passif [Termes IGN] déconvolution [Termes IGN] Glycine max [Termes IGN] Iowa (Etats-Unis) [Termes IGN] luminance lumineuse [Termes IGN] maïs (céréale) [Termes IGN] Passive and Active L and S band Sensor [Termes IGN] Soil Moisture Experiment [Termes IGN] température de luminance Résumé : (Auteur) An optimal deconvolution (ODC) technique has been developed to estimate microwave brightness temperatures of agricultural fields using microwave radiometer observations. The technique is applied to airborne measurements taken by the Passive and Active L and S band (PALS) sensor in Iowa during Soil Moisture Experiments in 2002 (SMEX02). Agricultural fields in the study area were predominantly soybeans and corn. The brightness temperatures of corn and soybeans were observed to be significantly different because of large differences in vegetation biomass. PALS observations have significant over-sampling; observations were made about 100 m apart and the sensor footprint extends to about 400 m. Conventionally, observations of this type are averaged to produce smooth spatial data fields of brightness temperatures. However, the conventional approach is in contrast to reality in which the brightness temperatures are in fact strongly dependent on land cover, which is characterized by sharp boundaries. In this study, we mathematically deconvolve the observations into brightness temperature at the field scale (500-800 m) using the sensor antenna response function. The result is more accurate spatial representation of field-scale brightness temperatures, which may in turn lead to more accurate soil moisture retrieval. Numéro de notice : A2004-415 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.02.019 En ligne : https://doi.org/10.1016/j.rse.2004.02.019 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26942 [article]