CBERS-04卫星宽视场成像仪在轨场地辐射定标  

Site Calibration of CBERS-04 WFI Using Reflectance-based Method

作　　者：刘李[1] 傅俏燕[1] 潘志强[1] 徐建艳 李晓进[1] 韩启金[1] 张学文[1] 刘涛[2] 

机构地区：[1]中国资源卫星应用中心,北京100094 [2]中国航天标准化研究所,北京100071

出　　处：《航天返回与遥感》2016年第1期89-96,共8页Spacecraft Recovery & Remote Sensing

基　　金：国家自然科学基金(41401424)

摘　　要：CBERS-04卫星宽视场成像仪(WFI)自发射以来,广泛应用于国土、水利、林业资源调查等方面。考虑到卫星遥感器受发射时的振动、在轨空间环境变化以及元器件电路系统老化等因素的影响,各种辐射特性的变化,遥感器的性能和灵敏度不断下降,从而导致整个遥感器辐射性能与原来的标定结果之间存在一定的偏差。2015年8月,通过在敦煌辐射校正场开展辐射定标同步观测试验获取了星地同步观测数据,根据反射率基法计算得到CBERS-04卫星WFI相机的场地定标系数。试验共获取了5次有效数据,根据2015年8月7日,10日,13日的定标试验数据拟合得到WFI的定标系数。同时,根据16日和19日两天的试验数据拟合得到一组新的定标系数作为准真值开展定标系数的验证。结果表明,WFI敦煌辐射定标结果的偏差小于4%。另外,在考虑WFI传感器光谱特性、辐射和空间分辨率、成像条件等差异的基础上,以具有较高辐射定标精度的Landsat-8 OLI作为参考传感器进行定标方法的相对验证,结果显示WFI与OLI的相对定标结果的不确定度在6%左右。CBERS-04 wide field imager （WFI） has been widely used in the land, water conservancy and forestry resources investigation. A satellite remote sensor is inevitably affected by the vibration of the launch, on-orbit space environment change and component aging. The influences of such factors lead to the change of radiation characteristics and the decline of performance and sensitivity of the sensor, which results in the deviation between the sensor＇s on-orbit performance and prelaunch calibration. In August 2015, synchronous observation data were obtained through site calibrations at Dunhuang correction field. Reflectance-based method was used to calculate the calibration coefficients of CBERS-04 WFI. The in-situ measurements on August 7th, 10th and 13th are used to calculate the calibration coefficients of WFI. The results determined by the August 16th, 19th data are used for validation. The validation results show that the relative deviation is less than4%. At the same time, Landsat-80LI was selected as the reference sensor to make cross verification of the site calibration results based on the varieties of the spectral characteristics, radiation and spatial resolution, and imaging conditions. The cross verification results show that the uncertainty between the calibration results of WFI and OLI is about 6%.

关 键 词：场地定标 验证 宽视场成像仪 中巴地球资源卫星 卫星应用 

分 类 号：TP732[自动化与计算机技术—检测技术与自动化装置]