一种适合机载SAR变换模式的PFA成像处理方法

Polar format algorithm for multi-mode airborne SAR imaging

针对机载合成孔径雷达(SAR)的实际需求,在详细分析条带转聚束模式的工作特点和对模式变换中的雷达回波信号进行精确建模的基础上,提出一种高效的成像处理方法.该方法通过运动补偿将条带成像与聚束成像相结合,并利用极坐标格式成像算法(PFA)对条带聚束变换模式进行成像,实现了模式变换前后数据处理结果的共用,既可以节省处理运算量和时间,也可以节省数据缓存空间,适合于机上实时成像处理器的实现.分析和仿真结果验证了方法的高效性和有效性.

A high efficiency processing method for mode switch is proposed based on the requirements of airborne synthetic aperture radar （SAR）. The features of the mode switch from stripmap to spotlight are well analyzed, and the precise echo signal model during the mode switch is established. By combining the processing steps by means of motion compensation, the polar format algorithm （PFA） is used for the multi-mode imaging. The processing results before and after the mode switch can be shared. Hence the processing efficiency is improved and hardware memory is reduced, which makes the method highly suitable for real-time imaging. Simulation results confirm the validity of the proposed method and show high efficiency.