A Focusing Algorithm for Circular SAR Based on Phase Error Estimation in Image Domain
Guo Zhen-yu*①②③ Lin Yun①② Hong Wen①②
①(Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China) ②(National Key Laboratory of Microwave Imaging Technology, Beijing 100190, China) ③(University of Chinese Academy of Sciences, Beijing 100049, China)
Residual motion error is common in high-resolution circular Synthetic Aperture Radar (SAR) image defocusing. The Signal-to-Clutter Ratio (SCR) in echo data domain is relatively low; thus, the phase error spans several range bins. To solve this problem, we propose a focusing algorithm for circular SAR based on phase-error estimation in the image domain. The method estimates the point-target image window interception and then the phase error from echo regeneration in the defocused image. Subsequently, the range migration error is calculated, and finally, the phase error in the echo data is compensated for azimuth focusing and range cell migration correction. Simulation and real-data processing verified the proposed method.
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Guo Zhen-yu, Lin Yun, Hong Wen. A Focusing Algorithm for Circular SAR Based on Phase Error Estimation in Image Domain. JOURNAL OF RADARS, 2015, 4(6): 681-688.
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2015, Vol. 4 
