面向GEO目标探测的面阵TDI空间相机  

Area array TDI space camera for GEO target detection

作　　者：何林[1] 邓武东[2] 宋立国[1] 张绪国[1] 黄业平[2] 刘雨晨 雷文平[1] He Lin;Deng Wudong;Song Liguo;Zhang Xuguo;Huang Yeping;Liu Yuchen;Lei Wenping(Beijing Institute of Space Mechanics and Electricity,Beijing 100094,China;Shanghai Institute of Satellite Engineering,Shanghai 201109,China)

机构地区：[1]北京空间机电研究所,北京100094 [2]上海卫星工程研究所,上海201109

出　　处：《红外与激光工程》2023年第9期168-174,共7页Infrared and Laser Engineering

摘　　要：为了提高远距离、暗弱目标探测灵敏度,通常需要增大可见光相机口径,这会显著增加相机的质量和体积,无法适应卫星轻小型化要求。针对低轨探测地球同步轨道(GEO)目标需求,利用低轨零倾角卫星与GEO目标相对速度恒定,设计了面阵相机时间延迟积分(面阵TDI)成像模式。与自然交会模式、面阵凝视模式相比,在不增加相机口径的前提下,大幅提高了相机探测灵敏度。阐述了面阵探测器TDI成像原理,推导了相机信噪比计算模型,对目标运动、积分时间、探测灵敏度和信噪比等主要成像参数进行了计算,分析对点目标探测成像的影响。研制了一台原理样机,在暗室条件下的实测结果表明,相机TDI级数为96级,可实现对GEO轨道目标探测能力优于15星等,信噪比大于5。Objective Space target detection is the basis of space situation awareness,and space-based space target observation can be independent of the geographical location of ground-based observation stations,with unique advantages.For geosynchronous orbit(GEO)targets,the current space-based system mainly uses optical observation means.In order to improve the detection sensitivity of distant and dim targets,it is usually necessary to increase the aperture of the visible light camera to increase the light collecting capacity.As a result,the weight and volume of the camera will be significantly increased,and the resource occupation and development cost of the satellite platform will be greatly increased.Therefore,it is necessary to study a new camera observation method,which can not only achieve higher sensitivity detection,but also meet the requirements of small and light payload for satellites.Methods In order to meet the requirements of observation GEO target from LEO,the time delay integration(TDI)push-scanning image technology of linear array CCD usually used in the earth observation camera is applied to the area array CCD,and the time delay integration(TDI)imaging mode of the area array camera is designed(Fig.2).According to the orbit characteristics of low-orbit zero inclination satellite,the GEO target speed with different inclination angles is analyzed(Tab.1),and the CCD charge transfer speed is designed to match the target speed.The point target signal is enhanced through charge accumulation,so as to improve the detection sensitivity of the camera.The principle of TDI imaging with area array is described,the calculation model of camera signal to noise ratio is derived,the main imaging parameters such as target motion,integration time,detection sensitivity and signal to noise ratio are calculated,and the influence on point target detection imaging is analyzed.In TDI mode,the east-west relative velocity of the target is compensated to zero(Fig.3),the north-south vertical image movement and the maximum integration t

关 键 词：GEO目标探测 空间相机 面阵TDI模式 低轨零倾角 星等 

分 类 号：V447.1[航空宇航科学与技术—飞行器设计]