俯冲段大斜视SAR子孔径成像二维空变校正方法  

Two-dimension Space-variance Correction Approach for Diving Highly Squinted SAR Imaging with Sub-aperture

作　　者：党彦锋[1,2] 梁毅[1,2] 别博文 丁金闪[1,2] 张玉洪 DANG Yanfeng1,2, LIANG Yi1,2,BIE Bowen1,2, DING Jinshan1,2, ZHANG Yuhong3(1National Key Laboratory of Radar Signal Processing, Xidian University, Xi＇an 710071, China ;2Collaborative Innovation of Information Sensing and Understanding, Xidian University, Xi＇ an 710071, China ;3School of Electronic Engineering, Xidian University, Xi＇an 710071, China)

机构地区：[1]西安电子科技大学雷达信号处理国家重点实验室,西安710071 [2]西安电子科技大学信息感知技术协同创新中心,西安710071 [3]西安电子科技大学电子工程学院,西安710071

出　　处：《电子与信息学报》2018年第11期2621-2629,共9页Journal of Electronics & Information Technology

基　　金：海洋公益性行业科研专项经费(201405001)~~

摘　　要：俯冲合成孔径雷达(SAR)常采用大斜视子孔径成像来满足平台机动性和处理实时性;而大斜视模式下距离方位的严重耦合、斜视角沿距离向的空变及3维速度和加速度的存在会导致距离包络和方位相位的2维空变,严重影响成像质量。针对这些问题,该文提出一种新的两级频域滤波算法,在预处理后,首先引入第1级频域滤波因子以校正距离包络沿方位位置的空变以实现距离徙动统一校正,然后采用第2级频域滤波校正方位多普勒参数的空变实现方位相位统一聚焦。仿真实验验证了该算法的有效性。The diving SAR usually adopts the highly squinted mode and sub-aperture to satisfy the maneuvering and real-time processing. However, the existence of severe range-azimuth coupling, range- dependent squint angle and three-dimension velocity and acceleration leads to the space variance of range envelope and azimuth phase, which makes imagery unfocused seriously. To solve these problems, a Two-stage Frequency Filtering Algorithm （TsFFA） is proposed. After preprocessing, the First-stage Frequency Filtering （FsFF） factor is first introduced to correct azimuth-dependent Range Cell Migration （RCM） and realize the unified RCM correction. Furthermore, the Second-stage Frequency Filtering （SsFF） factor is adopted to equalize azimuth-dependent Doppler parameters and realize unified azimuth phase focused. Simulation results are presented to validate the effectiveness of the proposed approach.

关 键 词：合成孔径雷达 子孔径 俯冲大斜视 两级频域滤波算法 2维空变校正 

分 类 号：TN957.52[电子电信—信号与信息处理]