收稿日期: 2016-01-20
修回日期: 2016-04-06
网络出版日期: 2016-09-15
基金资助
国家自然科学基金（61471340）资助
An SAR autofocus algorithm based on hybrid model
Received date: 2016-01-20
Revised date: 2016-04-06
Online published: 2016-09-15
提出一种基于混合模型的合成孔径雷达自聚焦算法.本方法用有限阶泰勒多项式估计低频相位误差，用自适应正弦多项式估计高频相位误差，解决了单一模型自聚焦算法对高频相位误差估计精度低的问题，提高了图像锐度和峰值旁瓣比，减小了主瓣宽度.在研究利用相位误差参数模型进行聚焦处理的基础上，分析基于混合模型实现最优锐度自聚焦算法的可行性，并通过仿真和实测数据处理验证了本方法的有效性.
关键词： 合成孔径雷达(SAR); 自聚焦; 高频相位误差; 混合模型
杨洋 , 王岩飞 . 一种基于混合模型的合成孔径雷达自聚焦算法[J]. 中国科学院大学学报, 2016 , 33(5) : 656 -663 . DOI: 10.7523/j.issn.2095-6134.2016.05.012
An SAR autofocus algorithm based on hybrid model is proposed. The hybrid model is a polynomial specially designed for focus filter. The hybrid model consists of two parts. The first part is a fixed-order Taylor polynomial to estimate the low frequency phase errors. The second part is an adaptive-order sinusoidal polynomial to estimate the high frequency phase errors. Through searching the hybrid model parameters, a better focus result is achieved when the phase errors contain more high frequency components. The simulation and experiment on real airborne SAR data demonstrate the validity and effectiveness of the proposed algorithm.
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