基于二阶Keystone变换的双站前视SAR成像算法

发布时间：2018-05-24 03:55

本文选题：双站前视合成孔径雷达 + 二阶KT变换　；参考：《现代雷达》2017年08期

【摘要】：由于回波信号具有剧烈的二维耦合和距离徙动特性,相比传统的单站合成孔径雷达(SAR)而言,双站SAR数据的成像处理更具有挑战性,双站前视SAR则更是如此。由于没有解决距离徙动的空变性和高阶距离-方位耦合,导致目前现存的成像算法效果较差,成像范围也受到较大限制。针对上述问题,文中提出了一种基于二阶Keystone变换(KT)和改进的非线性调频变标(NLCS)方法的成像算法。首先,利用线性距离徙动矫正去除线性距离徙动和多普勒中心频率;然后,采用二阶KT来补偿距离弯曲;最后,采用改进的非线性调频变标方法用于均衡不同点目标方位空变的多普勒调频率。仿真结果证明了该算法的有效性。
[Abstract]:Because of the intense two-dimensional coupling and range migration characteristics of echo signals, bistatic SAR data processing is more challenging than the conventional mono-static synthetic aperture radar (SAR), especially bistatic forward looking SAR. Due to the lack of resolution of range migration and high-order range-azimuth coupling, the existing imaging algorithms are less effective and the imaging range is limited. In order to solve the above problems, an imaging algorithm based on second-order Keystone transform and improved nonlinear frequency modulation and scaling algorithm is proposed in this paper. First, the linear range migration and Doppler center frequency are removed by linear range migration correction; then, the second order KT is used to compensate the range bending. An improved nonlinear frequency modulation scaling method is used to equalize the Doppler frequency of azimuth spatial variability of different points. Simulation results show the effectiveness of the algorithm.
【作者单位】：中国电子科技集团公司第五十一研究所;杭州电子科技大学通信工程学院;
【基金】：国家自然科学基金资助项目(61301248) 中国航天科技创新基金资助项目(20140795003)
【分类号】：TN957.52

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