直升机载ROSAR运动补偿及成像算法  

Motion Compensation and Imaging Algorithm for Helicopter-Borne Rotating Synthetic Aperture Radar

作　　者：束宇翔[1] 李东[2] SHU Yuxiang;LI Dong(The 38th Research Institute of China Electronics Technology Group Corporation,Hefei 230088,China;Key Laboratory of Aerocraft Tracking Telemetering&Command and Communication,Ministry of Education,Chongqing University,Chongqing 400044,China)

机构地区：[1]中国电子科技集团公司第三十八研究所,安徽合肥230088 [2]重庆大学飞行器通信与测控中心教育部重点实验室,重庆400044

出　　处：《雷达科学与技术》2018年第4期383-390,397,共9页Radar Science and Technology

摘　　要：针对传统旋转式合成孔径雷达(ROSAR)成像算法在直升机平台运动下难以实现有效的聚焦成像问题,提出一种融合直升机平台运动补偿的改进Chirp Scaling算法。首先建立了存在平台运动时直升机载ROSAR成像的几何模型,在此基础上,分析了平台运动引起的目标斜距误差随目标位置的变化关系,得到了平台运动引入的斜距误差的空变特性,并给出误差补偿方法。然后分析了雷达相位中心等效速度随目标斜距变化对成像质量的影响,并把其影响补偿融入到Chirp Scaling算法的距离徙动空变性校正和方位压缩中。仿真结果验证了所提方法的有效性。Traditional rotating synthetic aperture radar(ROSAR)algorithms are difficult to focus the scene due to the helicopter platform motion.To deal with the issue,an improved chirp scaling(CS)algorithm incorporating motion compensation for helicopter-borne ROSAR is proposed.Based on establishment of the geometric model of helicopter-borne ROSAR in the presence of platform movement,the relationship between the slant range error introduced by platform movement and the target position is analyzed.Then,the characteristics of the range-variant slant range error and the corresponding compensation method are given.The impact of the range-variant equivalent velocity of the phase center on the imaging quality is analyzed.And the proposed improved CS algorithm takes into account the range-variant velocity compensation during the space-variant range cell migration correction and the azimuth compression.The numerical results demonstrate the effectiveness of the proposed method.

关 键 词：直升机平台 旋转式合成孔径雷达 改进的Chirp SCALING算法 运动补偿 

分 类 号：TN957[电子电信—信号与信息处理]