机载大斜视条带SAR的高分辨聚束成像处理  

High Resolution Spotlight-mode Imaging of Airborne Highly Squinted Stripmap SAR Data

作　　者：肖靖[1] 胡学成[1] 章宏[1] 江卫[1] 

机构地区：[1]南京电子技术研究所,南京210039

出　　处：《现代雷达》2011年第1期29-32,共4页Modern Radar

摘　　要：基于条带模式和聚束模式合成孔径雷达的内在联系,提出一种将条带回波信号划分成等效聚束子孔径数据,并利用波数域算法进行聚束成像的方法。该算法首先对回波数据进行两维的频域匹配滤波,然后在距离波数域中利用Stolt插值变换获得两维均匀分布的地物反射率函数的重建频谱,最终通过IFFT成像。在实现场景地物成像处理的基础上,进而利用改进的"秩一"自聚焦算法实现剩余相位误差的估计及补偿,从而获得目标的高分辨图像。仿真及实测数据的成像效果验证了文中提出方法的可行性及有效性。Based on the inherent relationship between stripmap SAR and spotlight SAR, a method is proposed in this paper, which divides the squinted stripmap synthetic aperture into a set of subapertures and converts measured SAR signal in the subapertures into equivalent spotlight data, and then utilizes the wavenumber domain focusing algorithm to accomplish spotlight mode imaging. The algorithm firstly performs the two-dimensional frequency domain matched filtering of the SAR data, then takes advantage of the stoh interpolation conversion in the range wavenumber domain to obtain the evenly spaced samples of the reconstruction spectra of target reflection function, finally performs IFFT to achieve the focused images. After the completion of imaging procession, the modified ROPE autofoeus algorithm is used to estimate and compensate the residual phase errors so that to achieve the high resolution scene images. The imaging results of simulation and live data demonstrate the feasibility and validity of the method proposed in this paper.

关 键 词：合成孔径雷达 条带 聚束 波数域算法 改进“秩一”自聚焦 

分 类 号：TN958[电子电信—信号与信息处理] TN957.52[电子电信—信息与通信工程]