为保证卫星在轨自动化定标中气溶胶光学特性观测的精度, 针对基于相对稳定大气条件的Langley定标和基于高精度参考仪器的交叉定标, 开展了辐射校正场太阳光度计的现场定标技术研究.定标结果表明高精度太阳光度计Langley定标和交叉定标与CE318太阳光度计反演的气溶胶光学厚度最大偏差分别在0.015和0.01以内.计算分析了大气条件、仪器参数等对现场定标的影响, 将定标后的仪器和CE318太阳光度计放在青海湖同步比对观测, 气溶胶光学厚度最大偏差在0.01以内.敦煌辐射校正场太阳光度计现场定标误差对卫星在轨定标的影响不超过0.21%, 表明定标结果能够满足卫星在轨自动化定标的精度要求.

In order to ensure the accuracy of aerosol optical characteristics observation in onorbit automatic calibration of satellites, field calibration techniques of sunphotometer in Dunhuang test site were studied, including Langley calibration based on relatively stable atmospheric conditions and cross calibration based on high precision reference instruments. The calibration results show that the maximum deviations of aerosol optical depth inversion from high precision sunphotometer compared with CE318 sunphotometer are within 0.015 and 0.01 respectively by Langley method and crosscalibration method. The effects of atmospheric conditions and instrument parameters on field calibration were calculated and analyzed. The calibrated high precision sunphotometer and CE318 sunphotometer were placed in Qinghai Lake for synchronous comparison observation. The maximum deviation of aerosol optical depth is within 0.01. The influence of field calibration error of sunphotometer in Dunhuang test site on onorbit calibration of satellite is less than 0.21%, which shows that the calibration results can meet the accuracy requirements of satellite onorbit automatic calibration.