Due to the skew Region Of Support (ROS) of the two-dimensional wavenumber domain for high squint SAR data, conventional Omega-K algorithm can not exploit the ROS efficiently enough and degrades the resolution when choosing the square region to process. So a modified Omega-K algorithm is proposed in this paper to deal with the high squint SAR data for sub-aperture imaging. The maximum usage of ROS is obtained by the coordinate axis rotation. For the following azimuth dependence, the method of azimuth resampling is adopted to realize the uniform focusing. Compared with the traditional Omega-K method, the modified Omega-K algorithm is focused in azimuth wavenumber-domain because of the limitation of the azimuth sub-aperture ROS in order to avoid zero padding operation, and increase efficiency. Simulation results and raw data processing validate the effectiveness of the proposed algorithm.
怀园园,梁毅,李震宇,邢孟道. 一种基于方位谱重采样的大斜视子孔径SAR成像改进Omega-K算法[J]. 电子与信息学报, 2015, 37(7): 1743-1750.
Huai Yuan-yuan, Liang Yi, Li Zhen-yu,Xing Meng-dao. Modified Omega-K Algorithm for Sub-aperture High Squint SAR Imaging Based on Azimuth Resampling. JEIT, 2015, 37(7): 1743-1750.
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