卫星光学传感器全过程辐射定标

光学传感器全过程定标,就是对传感器从研发到使命终结整个过程的检测与定标,它包括在传感器研制过程中在实验室利用人工源和室外自然源对其辐射特性进行检测和定标,也包括建立与传感器一起工作的星上定标系统装置,以便当卫星发射升空传感器开始正常工作后,定期地应用星上定标系统对传感器响应的变化进行相对或绝对的定标,全过程定标同时包括在轨运行期间采用基于陆地(或海面)特性的“替代定标”,或借助其他卫星进行的“交叉定标”,最终依据定标结果来确定传感器使命的终结。全过程定标是一个系统实验过程,提高传感器应用效益是其目的,提高定标精度是目标,标准及标准传递是贯穿全过程定标的主线,为此而发展的定标系统和方法是全过程定标的技术支撑,本文作者及其研究室的工作涉及上述全过程的内容,本文首次将全过程定标所涉及的内容系统地予以阐述。提高定标的精度不仅要从系统硬件构成上考虑,如高精度低温绝对辐射计、传递标准探测器、积分球、标准板等,更需要从方法和实验上解决问题,如标准传递过程误差源的分析与控制,大气空间中辐射传输衰减校正模型以及相关的实验等。

Whole-Process Radiometric Calibration of Optical Remote Sensors

Whole-process radiometric calibration of optical remote sensors is testing and calibrating sensor through their lifetime.It includes testing and calibrating sensor with indoor artificial radiation sources or outdoor natural radiation sources in the research and development process and establishing on-board calibration system apparatus which will be used as periodically absolute and relative calibration for sensors being working after launch.Moreover,whole-process radiometric calibration of optical remote sensors also includes vicarious calibration based on land(or sea)surface and cross-calibration with other satellite sensor.At last,the result of calibration can be used as a criterion determining whether a sensor is out of function or not.Whole-process radiometric calibration is an experiment process.The intention is to aggrandize its application and aim is improving its accuracy.Some calibration systems and techniques have been developed for whole process radiometric calibration based on standard and standard transfer.The research works in our laboratory involve all contents of whole process radiometric calibration.We will introduce that completely.Improving calibration accuracy depends not only on hardware such as high accuracy cryogenic radiometer,transfer standard detector,integrating sphere and standard panel but also on techniques such as error source analysis and control in standard transfer process,determination of atmospheric radiative fluxes model and relational experiment,etc.