高分辨率光学遥感卫星小目标法在轨辐射定标  

In-flight radiometric calibration of high spatial resolution satellite optical sensor using small targets

作　　者：徐伟伟[1,2] 张黎明[1,2] 李鑫[1,2] 司孝龙[1,2] 杨宝云 XU Weiwei;ZHANG Liming;LI Xin;SI Xiaolong;YANG Baoyun(Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China;Key Laboratory of Optical Calibration and Characterization of Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[1]中国科学院安徽光学精密机械研究所,安徽合肥230031 [2]中国科学院通用光学定标与表征技术重点实验室,安徽合肥230031

出　　处：《应用光学》2019年第6期951-957,共7页Journal of Applied Optics

基　　金：国家自然科学基金(41601388);十三五航天预研基金(GFZX0401430407)

摘　　要：辐射定标是卫星遥感信息定量化的关键技术之一。高分辨率光学遥感卫星小目标法在轨定标将目标反射率的现场测量转换为实验室高精度测量,以实际测量代替气溶胶散射特性假设,通过简化辐射传输计算获取大气透过率与遥感器入瞳辐亮度,根据遥感器系统PSF检测结果将小目标的辐射响应与背景辐射相分离,降低对场区背景环境要求的同时提高了绝对辐射定标精度。试验结果分析表明,高分辨率光学遥感卫星传感器小目标法在轨辐射定标不确定度优于3%,与大面积辐射校正场或灰阶靶标法的定标结果差异3.65%,小目标法有望在全谱段范围实现高分辨率光学遥感卫星传感器的全动态范围定标与几何检校。Radiometric calibration is one of the key technologies for quantification of satellite remote sensing information. A calibration method for high resolution optical remote sensor was presented based on small targets. At the same time, the reflectance test on site was changed to accurate measurement in laboratory. It substituted the field actual determination to the assumption of aerosol scatter. The atmospheric transmittance and at-sensor radiance could be calculated by simplified radiometric transfer code. And the approach could isolate the digital number(DN) signal created by little targets from response produced by background radiance through system’s point spread function PSF estimation, which reduced the background requirement and improved the absolute radiometric calibration accuracy. The experimental results show that the calibration uncertainty is less than 3% for high spatial resolution satellite. The difference of calibration coefficient is less than 3.65% compared with large test site or gray-scale targets method. The small target approach is expected to achieve full dynamic calibration and geometric calibration in the full spectrum range for high resolution satellite optical sensor.

关 键 词：遥感 辐射定标 小目标法 系统PSF 大气透过率 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置] O435[自动化与计算机技术—控制科学与工程]