基于月球观测的FY-3D MERSI-Ⅱ在轨通道亚像元配准  

On-orbit Subpixel Registration of FY-3D MERSI-Ⅱ based on Lunar Observations

作　　者：程思行 徐娜[2] 吴荣华[2] 胡秀清[2] 何玉青[1] 肖达 汪子意 Cheng Sixing;Xu Na;Wu Ronghua;Hu Xiuqing;He Yuqing;Xiao Da;Wang Ziyi(School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China;National Satellite Meteorological Centre,China Meteorological Administration,Beijing 100081,China)

机构地区：[1]北京理工大学光电学院,北京100081 [2]中国气象局国家卫星气象中心,北京100081

出　　处：《遥感技术与应用》2021年第5期1072-1082,共11页Remote Sensing Technology and Application

基　　金：国家重点研发计划项目(2018YFB0504900、2018YFB0504802)。

摘　　要：月球目标具有受大气影响小且与背景温度差异明显的特点,可以作为通道配准非常稳定的参考源,用于分析不同通道的成像位置。以风云三号D星(FY-3D)搭载的第二代中分辨率光谱成像仪(MERSI-Ⅱ)为例,介绍了一种利用月球图像进行在轨通道配准的方法。通过对MERSI-Ⅱ各通道月球图像进行预处理,并对图像采取亚像元最大相关迭代的方法进行配准,得到亚像素精度的配准参数;利用月球质心距及灰度差值比较法对配准结果进行评价分析。结果表明:基于月球观测的配准方法具有较高的精度,与月球质心距结果一致性优于0.05像素。同时,利用月球配准结果对MERSI-Ⅱ基于发射前测试的配准结果进行了比对验证,发现目前MERSI-Ⅱ在轨配准偏差整体较小,但在短波通道的扫描方向存在0.5个像素左右的偏差,这对后续高精度的定量产品存在影响。利用该配准方法可以发现长期性的通道配准变化规律,为历史数据再定标及后续的定量化遥感产品开发应用打下基础。The lunar target has the characteristics of small atmospheric influence and obvious difference from the background temperature.It can be used as a very stable reference source for band registration to analyze the im⁃aging positions of different bands.Taking the second generation Medium Resolution Spectral Imager(MERSI-Ⅱ)on FY-3D as an example,a method of on-orbit registration using the moon is introduced.By preprocessing the moon image of each band of MERSI-Ⅱ,and adopting the method of sub-pixel maximum correlation itera⁃tion for image registration,the registration parameters of sub-pixel accuracy are obtained.The registration re⁃sults were evaluated and analyzed by comparing the centroid distance of the moon and the difference of gray lev⁃el.The results show that the lunar registration method has high accuracy and the consistency with the lunar cen⁃troid distance is better than 0.05 pixel.The registration based on the moon has the advantages of simple and effi⁃cient,and is not affected by the spectral differences of instrument bands.It is stable in the registration of absorp⁃tion bands,and is significantly better than other methods.The on-orbit registration results of MERSI-Ⅱbased on pre-launch test are compared and verified by the lunar registration results.It is found that the on orbit regis⁃tration deviation of MERSI-Ⅱis relatively small as a whole,however,there is 0.5pixel deviation in the scan⁃ning direction of the shortwave band,which has an impact on the subsequent high-precision quantitative prod⁃ucts.The method can be used to find the long-term change law of band registration,which lays a foundation for the re-calibration of historical data and the subsequent development and application of quantitative remote sens⁃ing products.

关 键 词：风云三号 MERSI-Ⅱ 月球观测 在轨空间特性 通道配准 

分 类 号：TP722[自动化与计算机技术—检测技术与自动化装置] V474.24[自动化与计算机技术—控制科学与工程]