基于联合运动参数快速估计的空间目标ISAR成像方法  

A ISAR Imaging Method for Space Targets Based on Fast Estimation of Joint Motion Parameters

作　　者：侯庆森 李光祚 徐仲秋 刘宸钰 洪文 吴一戎 HOU Qingsen;LI Guangzuo;XU Zhongqiu;LIU Chenyu;HONG Wen;WU Yirong(Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China;Research Department of Cyber-electromagnetic Space Information Technology,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China;School of Electronic,Electrical and Communication Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院空天信息创新研究院,北京100094 [2]中国科学院空天信息创新研究院网络电磁空间信息技术研究部,北京100094 [3]中国科学院大学电子电气与通信工程学院,北京100049

出　　处：《雷达学报(中英文)》2025年第2期424-438,共15页Journal of Radars

基　　金：中国科学院空天信息创新研究院科学与颠覆性技术项目资助(E3Z208010F)。

摘　　要：逆合成孔径雷达(ISAR)是空间目标成像和监测的重要手段之一,大转角下空间目标成像结果的越分辨单元徙动(MTRC)现象加剧,严重影响ISAR成像的性能。为快速估计和补偿空间目标运动产生的回波相位误差,结合BFGS优化算法效率高与极坐标格式变换算法(PFA)补偿精度高的优势,该文提出了一种基于联合运动参数快速估计的空间目标ISAR成像方法。所提方法建立了目标平动和转动参数联合估计的最小化图像熵优化模型;为降低优化陷入局部最优的可能,设计了目标参数粗估计和精估计的高效BFGS求解子步骤,实现了目标转动参数的快速估计与大转角情况下MTRC的补偿。点目标仿真和实测民航客机数据成像结果表明,相比PSO-PFA算法,所提方法在低信噪比条件下的运动参数估计精度更高,运算时间缩短为原来的五分之一,具有显著优势。Inverse Synthetic Aperture Radar(ISAR)is an important tool for imaging and monitoring space targets.The large rotation angle of space targets can exacerbate the phenomenon of Migration Through Resolution Cells(MTRC),seriously affecting the ISAR imaging performance.For the fast estimation and compensation of echo phase errors caused by the motion of space targets,this paper proposes an ISAR spacetarget imaging method based on the rapid estimation of joint motion parameters.This method combines the advantages of the high efficiency of the Broyden-Fletcher-Goldfarb-Shanno(BFGS)optimization algorithm and the high compensation accuracy of the Polar Format Algorithm(PFA)algorithm.The proposed method formulates an image entropy minimization model considering the joint estimation of the translation and rotation parameters of the target.To reduce the possibility of optimization falling into local optima,the proposed method solves sub-steps,which comprise rough and fine estimations of the target motion parameters,using the BFGS optimization algorithm.The proposed method rapidly estimates target rotation parameters and performs quick MTRC compensation under large rotation angles.The simulation of point targets and imaging results of actual civil aircraft data show that compared with the Particle Swarm Optimization-Polar Format Algorithm(PSO-PFA)algorithm,the proposed method estimates motion parameters with a higher accuracy under low signal-to-noise ratio conditions.Further,the computational efficiency is improved by more than five times,which is significantly advantageous.

关 键 词：空间目标 逆合成孔径雷达 越分辨单元徙动 极坐标格式变换算法 联合运动补偿 

分 类 号：TN957.52[电子电信—信号与信息处理]