BackForwardInstrument:  GRA 

Instrument details
Acronym GRA
Full name GEOSat Radar Altimeter
Purpose Ocean topography, significant wave height, wind speed on sea surface
Short description Single frequency, Ku-band (13.5 GHz)
Background Initially for military use, then open to civil
Scanning Technique Nadir-only viewing, continuous sampling along track
Resolution 25 km s.s.p.
Coverage / Cycle Global coverage in 1 month for 30 km average spacing, or in 10 days for 100 km average spacing
Mass Power Data Rate

 

Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1985 to 1990
Last update: 2012-05-15
Detailed characteristics
Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Earth observation instrument
  • Active and radio-occultation sensor
  • Radar altimeter
WIGOS Subcomponents
  • Subcomponent 1
  • Wide-swath radar altimeters, and high altitude, inclined, high-precision orbit altimeters
  • Conventional radar altimeter
Mission objectives
Primary mission objectives
  • Geoid
  • Ocean dynamic topography
  • Significant wave height
Evaluation of Measurements