高/中轨道卫星组网协同SAR系统优化设计与优化成像方法研究

With natural advantages of all-weather, all-time, global observation and high resolution, synthetic aperture radar (SAR) satellite plays an important role in military and civilian applications, such as national defense and military, scientific research and commercial use. Therefore, various countries pay attention to SAR satellite technology, and vigorously develop relevant theoretical research and application. Throughout the current status of SAR satellite technology, there are still institutional limitations, which are mainly reflected in the fact that they could not meet the requirement of “seeing visibly, seeing clearly, seeing quickly and seeing widely” at the same time. Aiming at this requirement, this project combines the special advantages of high-orbit radar satellite and satellite group, and thus proposes a high- /medium- orbit satellite SAR system with networking collaboration, which makes up for the limitations of previous systems. This project can break through the technical bottleneck of the existing radar satellite from theoretical algorithm and system design. From the key idea of “optimization to promotion”, this project focuses on solving the key technical issues of comprehensive optimization design of system parameters and the optimization imaging of object-oriented nonlinear trajectory and so on, which aims to improve the overall performance and imaging quality of the radar system by optimization means.

合成孔径雷达（Synthetic aperture radar, SAR）卫星凭借全天候、全天时、全球观测和高分辨等天然优势在国防军事、科研商用等军民应用领域发挥着重要作用，世界各国均高度重视合成孔径雷达卫星技术，大力发展相关理论研究和应用建设。纵观当前合成孔径雷达卫星的技术现状，依然存在着制度上的局限性，具体表现为难以同时实现“看的见，看的清，看的快，看的广”的应用需求。针对这一应用需求，本项目融合高轨道雷达卫星和集群卫星的特殊优势，提出了一种高/中轨道卫星组网协同的合成孔径雷达系统，弥补了以往合成孔径雷达卫星体制的局限性。本项目从理论算法和系统设计两方面突破现有雷达卫星的技术瓶颈，以“优化→提升”为核心思想，重点解决高/中轨道卫星组网协同合成孔径雷达系统综合优化设计、面向对象的非线性轨迹优化成像等关键技术问题，旨在通过最优化手段最大程度地提升该雷达系统的整体性能以及成像质量。

在中/高轨组网雷达成像新体制下，卫星的非线性轨迹运动与多基地协同的特点使得其系统参数设计与成像面临新的技术难题。本项目重点解决了系统成像性能评估、非线性轨迹成像、以及非线性轨迹误差估计与补偿等关键技术问题。主要提出了基于奇异值分解的系统性能评估方法、基于可控奇异值分解的非线性轨迹成像方法、以及基于子图像变标的非线性轨迹误差估计与补偿方法等。仿真与实测数据结果表明本项目所提的多个算法在通用性、精度和效率等方面均有较大的提升。.本项目在中/高轨组网的背景下解决了非线性轨迹SAR面临的多个基础共性问题，因此相关成果也可应用于诸如弹载平台、低轨超高分辨平台、机动平台和机载双基等平台。