@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/992ffede-af18-49a9-8acb-2cd333860efe>
  skos:prefLabel "Interferometers"@en ;
  a skos:Concept ;
  skos:narrower <https://gcmd.earthdata.nasa.gov/kms/concept/070eb17a-33d1-4255-bc7a-e4168c8e9e56> .

<https://gcmd.earthdata.nasa.gov/kms/concept/070eb17a-33d1-4255-bc7a-e4168c8e9e56>
  ns0:altLabel [ ] ;
  skos:definition """The Wind Imaging Interferometer (WINDII) on UARS determined 
temperature and winds in the mesosphere and the lower thermosphere by 
measuring both Doppler widths and shifts of isolated spectral lines 
emitted by airglow and aurora. The principal objectives were (1) 
measure 2-dimensional vertical profiles of horizontal wind velocity 
and Doppler temperature of the neutral atmosphere from 70 to 310 km as 
a function of latitude and time, (2) measure the global distribution 
of small-scale wave-like structures on a 3 km scale, and (3) studied 
the dynamic and thermal aspects of the neutral atmospheric energy 
balance. The WINDII instrument viewed the atmospheric limb 
simultaneously in two directions, 45 degrees and 135 degrees from the 
velocity vector. An imaging detector provided simultaneous 
measurements of temperature and wind profiles over the instrument's 
entire altitude range (70 to 310 km) with a vertical resolution of 2 
km and horizontal resolution of 20 to 100 km. Emission lines of OI, 
OH, O+ and O2 were measured to cover both daytime and nighttime over 
the altitude range and provide thermospheric ion wind velocities. The 
instrument was basically a CCD camera which viewed the Earth's limb 
through a field-widened Michelson interferometer. The instrument took 
4 images with the interferometer optical path difference changed by 
1/4 wavelength between images. From these images, the fringe phase 
(leading to wind velocity), fringe modulation (leading to 
temperature), and emission rate was determined. The Michelson optics 
consisted of a cemented glass hexagonal beamsplitter, a glass block 
with a deposited mirror and a glass block combined with an air gap and 
a piezoelectrically driven mirror. The CCD camera consisted of a fast 
camera lens and a 320 x 256 pixel detector array cooled to -50 C. 
Interference filters were mounted in a temperature-controlled filter 
wheel assembly to isolate specific spectral lines. 

See 
Reber, Carl A.,"The Upper Atmosphere Research Satellite",Trans., Am. Geophys. 
Union EOS, Vol. 71, No. 51, pp. 1867-1868,1873-1874,1878, December 18, 
1990.


Group: Instrument_Details
   Entry_ID: WINDII
   Group: Instrument_Identification
      Instrument_Category: Earth Remote Sensing Instruments
      Instrument_Class: Passive Remote Sensing
      Instrument_Type: Spectrometers/Radiometers
      Instrument_Subtype: Interferometers
      Short_Name: WINDII
      Long_Name: Wind Imaging Interferometer
   End_Group
   Group: Associated_Platforms
      Short_Name: UARS
   End_Group
   Online_Resource: http://disc.sci.gsfc.nasa.gov/UARS/documents/windii
   Online_Resource: http://www.trentu.ca/academic/windii/
   Creation_Date: 2016-01-08
End_Group"""@en ;
  skos:prefLabel "WINDII"@en ;
  skos:inScheme <https://gcmd.earthdata.nasa.gov/kms/concepts/concept_scheme/instruments> ;
  skos:broader <https://gcmd.earthdata.nasa.gov/kms/concept/992ffede-af18-49a9-8acb-2cd333860efe> ;
  a skos:Concept .

