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A measurement concept for hot-spot BRDFs from spaceSeveral concepts for canopy hot-spot measurements from space have been investigated. The most promising involves active illumination and bistatic detection that would allow hot-spot angular distribution (BRDF) measurements from space in a search-light mode. The concept includes a pointable illumination source, such as a laser operating at an atmospheric window wavelength, coupled with a number of high spatial-resolution detectors that are clustered around the illumination source in space, receiving photons nearly coaxial with the reto-reflection direction. Microwave control and command among the satellite cluster would allow orienting the direction of the laser beam as well as the focusing detectors simultaneously so that the coupled system can function like a search light with almost unlimited pointing capabilities. The concept is called the Hot-Spot Search-Light (HSSL) satellite. A nominal satellite altitude of 600 km will allow hot-spot BRDF measurements out to about 18 degrees phase angle. The distributed are taking radiometric measurements of the intensity wings of the hot-spot angular distribution without the need for complex imaging detectors. The system can be operated at night for increased signal-to-noise ratio. This way the hot-spot angular signatures can be quantified and parameterized in sufficient detail to extract the biophysical information content of plant architectures.
Document ID
19970019303
Document Type
Conference Paper
Authors
Gerstl, S.A.W.
(Los Alamos National Lab. NM United States)
Date Acquired
August 17, 2013
Publication Date
January 1, 1996
Subject Category
Earth Resources And Remote Sensing
Report/Patent Number
DE96-014621
LA-UR-96-2797
CONF-9609240-1
Meeting Information
Multiangular Remote Sensing: Measurements, Models, and Applications(Beijing)
Funding Number(s)
CONTRACT_GRANT: W-7405-ENG-36
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Keywords
Reflectivity
Laser Radiation
Detection
Plants
Canopies
Hot Spots
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