中文摘要：

频率非线性是制约调频连续波雷达距离分辨率的一个关键因素。针对系统非线性误差对调频连续波（frequency modulated continuous wave,FMCW）合成孔径雷达（synthetic aperture radar,SAR）成像处理的影响以及雷达系统实时成像处理的需求,对存在频率非线性误差的调频连续波SAR回波信号进行了建模,分析了调频连续波去斜接收模式下的回波特性,深入研究了系统非线性误差校正的问题,提出了一种改进的调频连续波SAR的非线性距离-多普勒成像处理算法。该算法通过非线性误差滤波器校正距离向非线性误差,具有计算量小,处理精度高的特点,适合实时成像处理。最后,通过理论推导和仿真分析,验证了算法的可行性和正确性。

英文摘要：

The limiting factor to the range resolution of frequency modulated continuous wave（FMCW） synthetic aperture radar（SAR） is the well-known presence of non-linearities in the transmitted signal.The impact of non-linearities in FMCW SAR is investigated,and the characteristics of beat signal are analyzed.Based on the model of FMCW SAR echo with non-linearities,a proper improved range-Doppler algorithm is proposed.This algorithm solves the non-linearities problem for the whole range profile through one non-linear filter.With the characters of low computation load and high processing precision,it is suitable for the de-chirped FMCW SAR real-time imaging.And the feasibility of the presented method is demonstrated by the simulation.