摘要
地球同步轨道SAR具有一般低轨SAR所不具备的优势。然而其"8"字形的运动轨迹也给成像带来了困难,基于直线运动的成像算法将失效。针对这个问题,利用了聚焦性能比较好的CS算法并结合偏航牵引控制和弯曲补偿的方法把弯曲的孔径拟合成直线再进行成像。本文分别对地球同步轨道SAR偏航牵引问题,等效斜视角进行了研究,详细推导了斜视工作模型下基于弯曲补偿改进的CS算法,根据分辨率的需求对地球同步轨道SAR大合成孔径进行子孔径处理,最后通过仿真验证了算法的成像性能。
Geosynchronous SAR has its own advantages which ordinary low orbit SAR doesn＇t have.However,the motion trajectory of ＂8＂ shape brings imaging difficult,and the imaging algorithms which are based on line motion also lose effectiveness.With regard to this issue,combining with yaw traction control and bend compensation,improved CS algorithm is proposed.In this paper,the geosynchronous SAR echo model,the yaw traction,the equivalent squint angle,and the formula of the improved CS algorithm are studied respectively.In order to solve the imaging problem,a large synthetic aperture is divided into small ones according to the requirement for resolution ratio.Simulations prove imaging properties of the algorithm.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2011年第1期179-186,共8页
Journal of Astronautics
基金
国防微波重点实验室基金项目
