光学遥感高精度时标设计实现与定位精度分析  

Design and Implementation of High-Accuracy Time Scale for Optical Remote Sensing and Analysis of Positioning Accuracy

作　　者：郑君[1,2] 张孝弘 褚备[1,2] 张弈秋 郑永超[1,2,3] Zheng Jun;Zhang Xiaohong;Chu Bei;Zhang Yiqiu;Zheng Yongchao(Beijing Institute of Space Mechanics and Electricity,Beijing 100094,China;Key Laboratory for Advanced Optical Remote Sensing Technology of Beijing,Beijing 100094,China;Beijing Aviation Intelligent Remote Sensing Equipment Engineering Technology Research Center,Beijing 100080,China)

机构地区：[1]北京空间机电研究所,北京100094 [2]先进光学遥感技术北京市重点实验室,北京100094 [3]北京市航空智能遥感装备工程技术研究中心,北京100080

出　　处：《光学学报》2024年第18期378-388,共11页Acta Optica Sinica

基　　金：民用航天技术预先研究项目(D010202)。

摘　　要：为实现高精度时标要求,光学遥感相机基于卫星高精度秒脉冲信号,结合对应的卫星整秒时刻数据,采用高精度本地时钟和计数同源设计以及图像辅助数据嵌入方案,能够计算出每行遥感图像对应的成像时刻。从相机成像时刻标定的设计原理出发,分析得出相机成像时刻标定的设计误差为±32μs,并且提出了相机时标精度的验证方法。依据本系统设计,时标精度测试误差为±2μs。通过实例验证了光学遥感相机时标设计的高精度实现。根据时间延迟积分推扫成像原理及实例分析,在遥感卫星时间同步系统精度层面,证明了光学遥感相机时标设计能够保证在轨影像几何定位的精度。Objective The time synchronization system of optical remote sensing satellites generally consists of a timing system and a timekeeping system.Its accuracy is determined by both the timing and the timekeeping accuracy:the timing accuracy is determined by the accuracy of the pulse per second signal output from the global navigation satellite system,while the timekeeping accuracy is determined by the imaging time calibration accuracy of the optical remote sensing camera during operation.As a timekeeping device,the time scale accuracy of the on-board optical remote sensing camera is an important technical indicator that directly affects the geometric positioning accuracy of remote sensing images.With the increasing demand for high temporal and spatial resolution satellite remote sensing data,optical remote sensing satellites require higher accuracy in their whole time synchronization systems.We discuss the design and verification of a high-accuracy time scale system based on the imaging mechanism and process of optical remote sensing cameras and analyze the influence of time scale accuracy and image positioning accuracy,demonstrating that the time scale accuracy of optical remote sensing cameras ensures the geometric positioning accuracy of in-orbit images.Methods We first analyze the influence of the time scale accuracy of optical remote sensing cameras on the geometric positioning accuracy of remote sensing images.The calibration accuracy of the imaging time directly affects the orbit and attitude accuracy through the satellite orbit parameters and satellite attitude parameters in the image auxiliary data,which affects the geometric positioning accuracy of remote sensing images.To achieve high-accuracy time scale performance for linear array remote sensing cameras,these cameras utilize high-accuracy local clocks and counting homology design,along with an image auxiliary data embedding scheme based on high-accuracy pulse-per-second signals from satellites combined with corresponding satellite integer second time dat

关 键 词：光学遥感 几何定位 时标 精度 秒脉冲 

分 类 号：V19[航空宇航科学与技术—人机与环境工程]