地表反射率数据库的构建及其应用

针对实现卫星对地观测的自适应多模态,需要根据先验判定卫星成像区域内地表覆盖类型及其反射率状况建立与太阳光照条件、地表覆盖类型、反射率相关的成像载荷积分时间、不同压缩比的成像参数设置模型,以选择最优的观测模式的问题,该文以中分辨率成像光谱仪(MERIS)地表反射率影像和GlobCover全球陆地覆盖分类图为数据源,建立了地表覆盖分类图及其反射率影像矢量化处理的技术流程,构建了以冰雪、沙漠、裸土、岩石、农作物、森林、草地、水体等不同地表覆盖类型及其在不同季节蓝、绿、红、近红外波段的地物反射率数据库。以此作为遥感卫星成像任务规划的技术支撑,构建自适应选择最优的观测模式,提升遥感图像的质量。

The building and application of land cover reflectance database

With the new generation technology of high spatial resolution,high spectral resolution,high radiant resolution and high temporal resolution remote sensing satellites developed rapidly and put into use widely,the adaptive multi-mode intelligent observation becomes the new trend of the development of satellite remote sensing system.In order to realize the adaptive multi-mode observation,the key step is to prejudge the land cover class and its reflectance of the imaging area.And then the optimal imaging parameters including integral time and compress ratio on-board are decided according to the sun illumination condition,land cover and land surface reflectance.In this paper,Medium Resolution Imaging Spectrometer (MERIS)surface reflectance images and 2009 GlobCover map are used to build the global cover knowledge database containing the different land cover class such as ice,snow,desert,soil,rock,forest,grassland and water,and its mean reflectance of blue,green,red and near infrared band in different season.Based on the land surface feature and its reflectance stored in the global cover knowledge database,the remote sensing satellite imaging mission programming system can predict what kind of optimal observation mode is adaptively selected to improve the payload imaging quality on orbit.