非均匀采样对偏置相位中心多波束SAR性能影响的分析

摘要

In this paper, influence of azimuth non-uniform sampling on SAR systems with multiple-receive apertures in azimuth is derived theoretically. The analysis shows that several ghosting peaks are presented around the main peak, and at the same time non-uniform sampling will cause peak gain loss and the broadening to the main beam. Formulas to calculate the Peek-to-Ghost-Ratio (PGR) and peak gain loss are given, which show that they are related to the degree of non-uniform and the azimuth oversampling ratio quantitatively. The correctness of these formulas is validated further by simulation experiments.%该文从理论上推导了方位向的非均匀采样对偏置相位中心多波束SAR性能的影响.分析表明方位向的非均匀采样会造成脉冲压缩的主峰两侧存在虚假峰值,同时它会造成脉冲压缩主峰增益降低、主峰展宽.文中给出了峰值-假目标比及主峰增益损失的计算公式,表明了它们与不均匀性及方位向过采样率等因素之间存在定量关系.这些公式的正确性通过仿真得到了进一步验证.