@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
@prefix ns0: <http://gcmd.gsfc.nasa.gov/kms#> .

<https://gcmd.earthdata.nasa.gov/kms/concept/944b7691-af37-4fb4-9393-c114e7997829>
  skos:prefLabel "Imaging Spectrometers/Radiometers"@en ;
  a skos:Concept ;
  skos:narrower <https://gcmd.earthdata.nasa.gov/kms/concept/574fd149-e30a-4762-8a43-34bc2fcfdc8c> .

<https://gcmd.earthdata.nasa.gov/kms/concept/574fd149-e30a-4762-8a43-34bc2fcfdc8c>
  ns0:resource [ ] ;
  ns0:altLabel [ ] ;
  skos:definition """AVNIR is a high spatial resolution optical sensor for observing land and coastal zones in visible and near-infrared regions. AVNIR has 4 spectral bands with a 16m spatial resolution and 1 panchromatic band with an 8 m spatial resolution. The AVNIR data will be useful for environmental awareness and monitoring of such phenomena as desertification, destruction of tropical forests, and pollution of coastal zones as well as for resource exploration, land use, etc.

AVNIR's field of view (FOV) is about 80km, picked up by lines of small pixels. Its FOV scans the entire earth's surface as the satellite moves. There are only a few other similar sensors, such as TM on LANDSAT. Among AVNIR's sensors are features which give the sensors high spatial resolution, a pointing function to change the observation field by +-40 degrees along the cross track, a 0.4rim band useful for coastal zones and lakes, an optical calibration function which uses solar light and lamps, as well as others.

AVNIR is composed of two units, the Scanning Radiometer Unit (SRU) which is mainly composed of optical components and the Electronic Unit (ELU) which includes mainly electronic components. Optics in SRU adopts a Catadioptric Schmidt optical system to reduce aberration in a wide field of view. Large mirrors used in Optics and Pointing Mechanism Assembly are ultralight mirrors weighing 50 to 70% less than conventional mirrors, made from low expansion material. CFRP with low thermal and moisture expansion properties is used as the truss structural material in order to make Optics light yet extremely precise in orbit. The large linear-array CCDs with 5,000 and 10,000 pixels are used as detectors and deliver high spatial resolution. Observation data is compressed in the Image Processing Assembly by about 10% in order to reduce the transmission data rate. 

[Summary provided by the Japan Aerospace Exploration Agency.]


Group: Instrument_Details
   Entry_ID: AVNIR
   Group: Instrument_Identification
      Instrument_Category: Earth Remote Sensing Instruments
      Instrument_Class: Passive Remote Sensing
      Instrument_Type: Spectrometers/Radiometers
      Instrument_Subtype: Imaging Spectrometers/Radiometers
      Short_Name: AVNIR
      Long_Name: Advanced Visible and Near-Infrared Radiometer
   End_Group
   Group: Associated_Platforms
      Short_Name: ADEOS-I
   End_Group
   Group: Spectral_Frequency_Information
      Wavelength_Keyword: Visible
      Spectral_Frequency_Coverage_Range: 0.42 μm - 0.50 μm
   End_Group
   Group: Spectral_Frequency_Information
      Wavelength_Keyword: Visible
      Spectral_Frequency_Coverage_Range: 0.52 μm - 0.60 μm
   End_Group
   Group: Spectral_Frequency_Information
      Wavelength_Keyword: Visible
      Spectral_Frequency_Coverage_Range: 0.61 μm - 0.69 μm
   End_Group
   Group: Spectral_Frequency_Information
      Wavelength_Keyword: Near Infrared
      Spectral_Frequency_Coverage_Range: 0.76 μm - 0.89 μm
   End_Group
   Online_Resource: http://www.eorc.jaxa.jp/en/hatoyama/satellite/sendata/avnir_e.html
   Sample_Image: http://www.eorc.jaxa.jp/hatoyama/satellite/sendata/image/avnir_pic.gif
   Creation_Date: 2008-08-20
   Group: Instrument_Logistics
      Instrument_Start_Date: 1996-08-17
      Instrument_Owner: Japan Aerospace Exploration Agency
   End_Group
End_Group"""@en ;
  skos:prefLabel "AVNIR"@en ;
  skos:inScheme <https://gcmd.earthdata.nasa.gov/kms/concepts/concept_scheme/instruments> ;
  skos:broader <https://gcmd.earthdata.nasa.gov/kms/concept/944b7691-af37-4fb4-9393-c114e7997829> ;
  a skos:Concept .