Synthetic Aperture Radar at The Alaska SAR Facility by yurtgc548

VIEWS: 2 PAGES: 9

									Synthetic Aperture Radar at
 The Alaska SAR Facility



          Chris Wyatt
         Data Specialist
       cwyatt@gi.alaska.edu
          (907) 474-7312
        www.asf.alaska.edu
                 Overall Mission
• The Alaska SAR Facility provides satellite data, software
  tools and information to the science community and
  government operational agencies in support of polar research
  and earth science.
                   What is SAR?
• Synthetic Aperture Radar (SAR) is an active remote sensing
  technology that uses microwave energy to illuminate the
  surface.
• The system records the elapsed time and energy of the return
  pulse received by the antenna.
• At wavelengths of about 2 cm, these instruments can collect
  data about the Earth’s surface day or night, regardless of
  cloud cover.
                       Backscatter
• Definition: the amount of energy returned to the receiver,
                which determines the brightness of the pixel
• Backscatter is a function of:
           • wavelength and incidence angle of the radar signal
           • roughness and dielectric constant of the reflecting surface
                Applications of SAR
•   Sea ice characteristics   •   Land cover
•   Flooding                  •   Volcanology
•   Archaeology               •   Glaciology
•   Ocean circulation         •   Phytoplankton distribution
•   Wetlands                  •   Soil moisture
•   Structural geology        •   Crustal deformation
             ASF User Community
•   Worldwide user community
•   170+ projects
•   Multiple principle investigators
•   Graduate students
•   Undergraduate students
•   Interns
•   Sun workstations and SGIs
            Foreign Missions Supported
Satellite      Agency     Launch Date   Avg. Data
                                        min/month

ERS-1          ESA        July 1991     1000-1100


ERS-2          ESA        April 1995    1000-1100


JERS-1         NASDA      Feb 1992      800


RADARSAT       CSA/NASA   Nov 1995      1500-1800
                    SAR User Tools
                   Development Status

                Tool                ERS-1   ERS-2   JERS-1    RADARSAT
Tape Reader                         Done    Done     Done        Done
Radiometric Calibration             Done    Done     Done        Done
CEOS Metadata Handlers              Done    Done     Done        Done
Orbit Prediction Tools              Done    Done     Done         TBD
Image to Geographic Coord. Trans.   Done    Done     Done        Done
Automatic Geocoding                 Done    Done     Done        Done
Auto Terrain Correction             Done    Done     TBD          TBD
Normalized Incidence Angle          Done    Done     TBD          TBD
Change Detection Tools               TBD     TBD     TBD          TBD
Signal Domain Tools                  TBD     TBD     TBD          TBD
RGPS Tools                            NA      NA      NA     <in progress>
  EOS-HDF data available at ASF
• Current data availability
   • SAR imagery is available only in CEOS format
   • Derived products (GPS products) are available in custom binary or ascii
     formats
• Future plans
   • ASF would like to support EOS-HDF formatted SAR imagery products -
     this will most likely occur when the ECS is installed at ASF
   • ASF currently assessing applicability of EOS-HDF for RGPS products
     (ice motion, ice age, ice thickness, open water fraction, melt onset/freeze
     up, wind/temp/pressure field products)

								
To top