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The ZY-3 satellite plays an important role in agriculture, forestry, water conservancy, ecological environment, and
so on since its successfully running. In order to achieve continuity, stability and reliability of the remote sensing
data, and improve quantitative application level of the ZY-3 satellite data, an accurate sensor radiometric calibration
is essential. Because ZY-3 satellite doesn’t have onboard calibration system, in-fight filed absolute radiometric
calibration as a means to effective monitor the radiometric stability.This paper uses multi-day, multi-field at the
Dunhuang test site to calibrate the ZY-3 multispectral sensor. The experiment obtained a synchronization
measurement data on the August 18, 23 and 28, respectively. The two of ground surface were selected for
measuring reflectance, which middling reflectance field (20%) and high reflectance field (40%). At the time of the
ZY-3 overpass on the site, synchronous measure surface reflectance of ground targets, atmospheric optical
characteristics parameters, such as atmospheric aerosol optical depth, atmospheric columnar water vapor content.
Then use the radiative transfer model to estimate the top of atmosphere (TOA) radiance for MSS band. Radiometric
calibration coefficient of MSS band was estimated by comparing the TOA radiance with average digital number of
the MSS image. Based on multi-day, multi-field, and the real-time measurement at the Dunhuang site, radiometric
calibration for ZY-3 MSS was successfully performed using reflectance-based method and calibration coefficients
for MSS bands were obtained as well. According to contrast between in-fight calibration and the prelaunch, it was
shown that the response of MSS changed at some extent after launch, especially band 1 and band 4. As a result, it
was quite essential to update calibration coefficient timely and periodically in order to monitor the change of ZY-3
MSS better and to improve the quantitative application of MSS data as well.
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