HJ-1星CCD相机场地辐射定标与真实性检验研究

Radiometric Calibration and Validation of CCD Cameras on HJ-1 Satellite

为了满足HJ-1星遥感数据定量化应用的需求,2008年10月中旬,以敦煌定标实验场为地面目标,采用反射率基法对HJ-1A和HJ-1B星的CCD相机开展场地绝对辐射定标,以确定CCD相机响应的变化,并对得到的定标结果进行了误差分析。同时利用非定标同日的敦煌场和贡格尔实验场的CCD星地同步数据得到的表观辐亮度作为标准值,对定标系数进行真实性检验研究。结果表明,定标系数模拟出的CCD表观辐亮度与标准值非常接近,误差均小于3%。研究表明:此次定标实验的结果精度高,并将两次同步数据的定标系数平均值作为定标系数结果,为CCD相机定量化应用研究奠定了良好基础。

To meet demand of quantitative application for HJ-1 satellite data,a vicarious calibration experiment for CCD cameras onboard HJ-1A and HJ-1B satellites was proposed in the middle of October 2008.The reflectance-based method was used.The radiometric response change of each CCD camera was ascertained and error analysis of the calibration coefficients was developed.Meantime,regarding apparent radiances obtained from CCD data of the synchro measurements at Dunhuang test site and Gongger test site as the standard values,which were not at the same day as the calibration experiment,validation research of the calibration coefficients was performed.It showed that the apparent radiances obtained by calibration coefficients were fairly consistent with the standard values and the errors were all less than 3%.It was proved that the calibration result has high accuracy.And then an average value of calibration coefficients from both synchro data was determined as the last result.The result laid the good foundation for quantitative application of CCD cameras.