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Automatic observation for calibration of satellite remote sensors is used widely in the past few years, which usually two or three automatic observation instruments for necessary characteristics, such as surface reflectance, aerosol optical depth and diffuse irradiance for more calibration accurate, are placed in the site. In this paper, an automated precision ground-solar-sky radiometer (GSSR) is developed with constant temperature for Si and InGaAs detectors avoiding the influence of temperature drift of detector responsivity and BeiDou terminal for data transmission. The radiometer is equipped with three aperture tubes, one for measuring the direct solar irradiance and the sky diffuse radiance, and the other two for measuring the surface reflectance. When the satellite overpass, it can adjust to consistent observation azimuth with the remote sensors eliminating the effect of bidirectional reflectance. The radiometric calibration of irradiance channels are carried out with Langley method and the radiance channels with the lamp-panel system (LPS) method and the solar radiation-based calibration (SRBC) method. The deviation of the calibration coefficients obtained by two independent calibration methods LPS and SRBC is less than 3% in band 1-7, indicating that the calibration results are accurate.
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