机载斜视SAR改进ETF快速成像算法

 根据机载斜视SAR(Synthetic Aperture Radar)成像模式，详细推导了任意场景位置的准确传递函数，在此基础上，提出了一种改进的ETF（Exact Transfer Function）成像算法。并推导得到了算法使用中分块处理应该满足的边界条件。由于推导过程基于准确运动模型和参考距离模型，方位相位的计算不做近似截取而是做准确计算，使得该算法具有更高的相位精度。同时该算法可运行于现有的成像系统，兼容性好；对数据分块并行运算，解决了斜视情况下大距离徙动带来的问题并且提高了运算速度。最后，点目标仿真成像结果证明了算法的有效性。

Improved Fast ETF Algorithm for Airborne Squint SAR Imaging

According to the airborne squint SAR (Synthetic Aperture Radar) imaging mode, th e exact focusing function for arbitrary scene position is evoluted in details an d then an improved fast ETF(Exact Transfer Function) algorithm is further propos ed in this paper. Because the evolution is based on exact motion model and exact reference range model, as well as precise computing instead of approximate trun cation for azimuth phase preservation, the algorithm performs distinguished phas e precision. The algorithm requires no interpolation processing and no linear FM signal constraint, so that it has fine imaging precision and applicability. Mea nwhile the algorithm can be easily incorporated into processors using convention al algorithms,blocks and parallel processing compensated varying Doppler centro id complexity and accelerate the processing. Results for processing simulated po int targets show the validity of the algorithm.