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Table 1 : Main characteristics of the sensor of the Earth Resource Satellite ZY-1
Sensor
CCD camera
Infrared scanner
Spectral bands (pm)
I II
0.52 - 0.59 0.45 - 0.52
0.63-0.69 0.51 -0.73
0.77 - 0.89 0.77 - 0.89
0.5- 1.1
1.55-1.75
2.08 - 2.35
10.4 - 12.5
Resolution
19.5 m
near infrared < 80 m
Thermal IR <160 m
Thermal resolution <1.2 K
Revisit capability
26 days
26 days
Swath width (km)
116.7
119.4
Transmission rate
53 Mb/s x 2
10 Mb/s
1.2. Main characteristics of the sensor of the meteorological satellite FY-2
The meteorological satellite FY-2 is equiped with three spectral bands. Their characteristics and the
corresponding ground resolutions are given in Table 2.
Table 2 : Spectral bands and ground resolution of the meteorological satellite FY-2.
Channels
Visible-near-infrared
Water vapor
Thermal IR
Spectral bands (pm)
0.55-1.05
6.2 - 7.6
10.5 - 12.5
Ground resolution
1.4 km
5.7 km
5.7 km
2 - SELECTION OF THE RADIOMETRIC TEST SITES IN CHINA
Considering the radiometric calibration test sites developed by France (La Crau) and USA (White Sands), it
has been primarily decided to establish a Chinese test site in Qinghai and Gansu Province in north-west China.
The choice was done after having analyzed and compared a large amount of satellite images, aerial
photographs, as well as meteorological and geological data.
In Qinghai and Gansu Provinces, many Gobi and salt lakes can be chosen as calibration test sites for
satellite sensors in visible, near infrared and thermal infrared bands. These sites are perfectly leveled, the
surface feature is stable and has good optical properties, the considered areas are wide, the communication and
transportation are easy. The altitude ranges between 1200 and 2800 m, the area is far from large cities, the
climate is dry and the atmospheric aerosol content is reladvely low. These excellent environmental conditions
make possible the construction of a calibration test site for satellite sensors enabling accurate measurements.