舰船目标混合式SAR/ISAR成像算法研究  

Research on hybrid SAR/ISAR imaging algorithm of ship target

作　　者：曹晔 师亚辉 闫海鹏 张剑琦 CAO Ye;SHI Yahui;YAN Haipeng;ZHANG Jianqi(Beijing Research Institute of Telemetry,Beijing 100076,China)

机构地区：[1]北京遥测技术研究所

出　　处：《遥测遥控》2019年第5期34-41,共8页Journal of Telemetry,Tracking and Command

摘　　要：针对高动态平台和大斜视角成像条件下运动舰船成像模糊的问题,从提高成像处理各个环节的精度的角度出发,提出了一种基于加速度模型的混合式SAR/ISAR成像算法,实现了两种算法的有效融合:首先利用运动估计结合距离徙动校正完成回波包络粗对齐,同时在距离多普勒域通过相位滤波去除调频率空变,然后通过相关对准实现包络精对齐,补偿由于运动估计不准、模型失配以及惯导测量等引入的误差,最后结合加权多特显点自聚焦法对剩余非空变相位项进行统一校正。仿真结果表明,所提算法能够有效改善成像效果,得到聚焦良好的目标图像。Aiming at the problem of fuzzy imaging of moving ship target under high dynamic platform and large squint angle,this paper proposes a hybrid SAR/ISAR imaging algorithm based on acceleration model from the perspective of improving the accuracy of each part of imaging processing.The effective fusion of the two algorithms is achieved.Firstly,the motion estimation is combined with the distance migration correction to complete the roughly alignment of the echo envelopes,and at the same time,the phase modulation is eliminated by phase filtering in Range-Doppler domain.Then the accurate envelope alignment is achieved by correlation alignment to compensate the errors caused by the motion estimation inaccuracy,the model mismatch and the inertial measurement.Finally,the residual non-space-variant phase term is uniformly corrected by the weighted multi-special point autofocus method.The simulation results show that the proposed algorithm can effectively improve the imaging effect and obtain a well-focused target image.

关 键 词：混合式SAR/ISAR 舰船目标 平动补偿 高分辨成像 

分 类 号：TN958[电子电信—信号与信息处理]