中文摘要：

低飞平台大斜视SAR因高度低、速度快、斜视角大而对脉冲重复频率设计提出更高要求，斜视角过大导致多普勒中心远离零点，基于传统成像方法会面临严重散焦问题。文章针对低飞平台大斜视SAR成像问题，建立脉冲重复频率与斜视角间关系模型，从避免距离模糊、方位模糊、回避发射波干扰等出发，以实现高分辨率成像为目的，合理设计脉冲重复频率，解决了成像中散焦问题，基于STOLT插值，利用ω-κ成像算法处理原始数据，得到了良好成像效果。仿真证明该算法可有效解决大斜视平台SAR成像问题。

英文摘要：

Higher requirement of pulse repetition frequency will be faced when Synthetic Aperture Radar（SAR） has low height, high velocity and large squint angle. Too large squint angle will cause doppler centroid frequency deviate from zero greatly, if we still use traditional imaging algorithm, image will defocus. According to the problem of imaging of low-plat- form and squint-looking SAR, in order to avoid range and azimuth ambiguity and the interference coming from the transmit- ted pulses, and get high resolution image, designing method of pulse repetition frequency is studied, as a result, the prob- lem of image defocusing is solved. After STOLT interpolate mapping, raw data is properly processed with ω-κ algorithm, and good imaging result is gotten. Simulation results testified that the algorithm can solve the problem of imaging of low height and large squint SAR.