摘要
分析了星载聚束式合成孔径雷达 (SAR)的信号特性 ,主要研究了多普勒中心频率、多普勒带宽以及脉冲重复频率 (PRF)与斜视角的关系 .基于改进的ChirpScaling算法 ,处理时采用了子孔径方法 .通过子孔径方法 ,可以有效降低数据率及雷达发射峰值功率 ,并可解决多普勒中心频率的时变问题 .此外 ,分析了偏航控制对于实现精确成像的必要性 ,给出偏航控制规律 ,证明偏航控制可以有效减小距离徙动量 ,降低成像处理难度 .最后 ,通过计算机仿真 ,验证了处理方法的有效性 .
Signal properties of spaceborne spotlight SAR (synthetic aperture radar) were discussed. The relations of centroid Doppler, Doppler bandwidth and pulse repetition frequency with squint angle were analyzed. Based on a modified Chirp Scaling algorithm, a subaperture method was used, so that the data rate and radar transmit peak power can be reduced, and the time variability of Doppler center frequency can be resolved. The necessity of yaw steering was analyzed, and a yaw steering rule was given. It was proved that yaw steering can be used to decrease range migration and reduce imaging difficulties. The validity of the processing method was tested by computer simulation.
出处
《北京航空航天大学学报》
EI
CAS
CSCD
北大核心
2002年第6期643-647,共5页
Journal of Beijing University of Aeronautics and Astronautics
关键词
合成孔径雷达
成像
偏航控制
子孔径方法
星载雷达
Algorithms
Computer simulation
Doppler effect
Image processing
Space applications
