Owing to the platform instability and precision limitations of motion sensors, motion errors negatively affect the quality of synthetic aperture radar (SAR) images. The autofocus Back Projection (BP) algorithm based on the optimization of image sharpness compensates for motion errors through phase error estimation. This method can attain relatively good performance, while assuming the same phase error for all pixels, i.e., it ignores the spatial variance of motion errors. To overcome this drawback, a high-precision motion error compensation method is presented in this study. In the proposed method, the Antenna Phase Centers (APC) are estimated via optimization using the criterion of maximum image intensity. Then, the estimated APCs are applied for BP imaging. Because the APC estimation equals the range history estimation for each pixel, high-precision phase compensation for every pixel can be achieved. Point-target simulations and processing of experimental data validate the effectiveness of the proposed method.
作者简介: 胡克彬(1988-)，男，四川人，目前为电子科技大学工学博士研究生，主要从事高精度SAR成像技术研究。E-mail: kbhu_work@126.com
张晓玲(1964-)，女，四川人，获电子科技大学工学博士学位，目前为电子科技大学教授/博士生导师，主要从事SAR成像技术、雷达探测技术研究。E-mail: xlzhang@uestc.edu.cn
师 君(1979-)，男，河南人，获电子科技大学工学博士学位，目前为电子科技大学副教授，主要从事SAR 数据处理方面研究。E-mail: shijun@uestc.edu.cn
韦顺军(1983-)，男，广西人，获电子科技大学工学博士学位，目前为电子科技大学讲师，主要从事 SAR 成像技术、干涉 SAR 技术研究。E-mail: weishunjun@uestc.edu.cn
引用本文:
胡克彬,张晓玲,师 君,韦顺军. 基于图像强度最优的SAR高精度运动补偿方法[J]. 雷达学报, 2015, 4(1): 60-69.
Hu Ke-bin,Zhang Xiao-ling,Shi Jun,Wei Shun-jun. A High-precision Motion Compensation Method for SAR Based on Image Intensity Optimization. JOURNAL OF RADARS, 2015, 4(1): 60-69.
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