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left.gifKind of Earth Observation Satellite
spacer.gifsub_directry_end.gifADEOS
left_on.gifKind of sensor
spacer.gifsub_directry.gifADEOS AVNIR
spacer.gifsub_directry.gifADEOS OCTS
spacer.gifsub_directry.gifADEOS NSCAT
spacer.gifsub_directry.gifADEOS TOMS
spacer.gifsub_directry.gifADEOS POLDER
spacer.gifsub_directry.gifADEOS IMG
spacer.gifsub_directry.gifADEOS ILAS
spacer.gifsub_directry_end.gifADEOS RIS
left.gifFirst Image
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OCTS Image

Overview

OCTS is an optical radiometer devoted to the frequent global measurement of ocean color and sea surface temperature. OCTS will show the amount of chlorophyll and dissolved substances in the water, and temperature distribution. OCTS data will be used for determination of ocean primary production and carbon cycle, and be used for getting the information of ocean conditions for fishery and environment monitoring etc. OCTS is a successor to CZCS (Coastal Zone Color Scanner), the U.S. projects, which was the first real optical sensor for ocean observation onboard NIMBUS-7 launched in 1978.

OCTS has 8 bands in visible and near-infrared region and 4 bands in thermal region, and achieves highly sensitive spectral measurement with these bands. The observation bands are determined on the characteristics of spectral reflectance of the object substances, atmospheric windows and atmospheric correction. The spatial resolution is about 700m. This is applicable to the observation of coastal zone and land, the feature of these area barriers quickly compared to the open ocean. As the swath width is about 1400km on the ground, OCTS can observe the same area every 3 days and can monitor rapidly changing phenomena. OCTS has optical calibration function using solar light and halogen lamp as the calibration source. OCTS has two data transmission modes. All raw pixel data are transmitted through X band with fine data transmission mode. One pixel data is sampled from every 6x6km area as typical data of the area and is transmitted at UHF band in coarse data transmission mode.

OCTS consists of scanning radiometer unit, which contains optical system and detector module, and-electrical unit. OCTS adopts catoptric optical system and mechanical rotating scanning method using mirror. this is because OCTS covers wide range of wavelength and wide scanning angles. OCTS can tilt its line of sight along the track to prevent the sunglitter at the sea surface from interrupting the observation. For high sensitivity, each band has 10pixels aligned to the track. The infrared detectors are cooled at 100k by a large radiant cooler facing the deep space.


Characteristic

Instantaneous Field Of View 0.85mrad(Ground Surface - 700m)
Scanning Range - +-40deg.(ground level distance 1400km)
MTF 0.35
Polarization sensitivity Band 1 : 5% or less
Band 2-8 : 2% or less
Tilt Angle -20deg. ,0deg., +20deg
Collaboration
VNIR
: Solar,Internal Light Source
IR
: Deep Space, Black Body
Quantization 10bit/pixel
Course Data Transmission(DTL) 4Bands(443nm,565nm,665nm,11.0mm)




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