针对变速运动平台,提出了一种基于级数反演法的SAR回波模拟二维频域的算法。建立了变速运动模式SAR的几何模型,利用级数反演法,得到了较为准确的信号2维频谱表达式,并对由变速运动引入的大场景空变性进行了分析,给出了空变性相位误差补偿因子,实现了回波信号的精确仿真。分析表明该算法能够在保证较高的相位精度情况下大大的提高SAR回波的仿真速度。仿真结果证明了该算法的有效性。
Considering the platform with variable velocity, a 2-D frequency domain algorithm for SAR echo signal simulation is presented. Because it is difficult to obtain its two-dimensional frequency spectrum by use of a curvilinear trajectory with varying velocity, based on the geometric model of a side-looking SAR and reversion of series, the 2-D spectrum can be derived accurately. Moreover, the range-variant problem is analyzed and effectively solved by introducing a new compensation function. The results show that the efficiency of SAR echo signal simulation can be improved with high phase accuracy. Several simulation and processing results are presented to demonstrate the validity of the proposed algorithm.