建立典型滑动聚束SAR(合成孔径雷达)斜视成像模型.在考虑不同方位目标回波信号多普勒空变性的情况下,详细分析两步算法方位滤波恢复滑动聚束SAR方位欠采样信号的原理.对结合两步算法和传统CS算法的ECS算法进行了在斜视成像模型下的修正.针对滑动聚束工作模式的特点,讨论其中关键处理参数的选择问题,给出算法的处理流程.最后,用计算机仿真实验验证了方法的有效性.
A squint imaging model for typical sliding spotlight SAR is proposed. Considering the azimuth space-variant characteristic of Doppler parameters, the basic rationale and the implementation of azimuth data filtering are analyzed. The ECS algorithm, which combines the two-step approach and the traditional CS algorithm, is amended within the squint imaging model. In addition, the choice of its pivotal processing parameters is discussed in detail. Finally, the algorithm is validated by computer simulation.
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