无人机载多普勒分集前视合成孔径雷达成像方法  

Imaging Technology of Doppler Diversity Forward-looking SAR Imaging for Unmanned Aerial Vehicle

作　　者：孟智超 卢景月 谢朋飞 张磊 王虹现[1] MENG Zhichao;LU Jinyue;XIE Pengfei;ZHANG Lei;WANG Hongxian(National Key Laboratory of Radar Signal Processing,Xidian University,Xi’an 710071,China;School of Electronic and Communication Engineering,Sun Yat-sen University,Guangzhou 510275,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]中山大学电子与通信工程学院,广州510275

出　　处：《电子与信息学报》2019年第12期2852-2858,共7页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(61771372,61771367);上海市自然科学基金(16ZR1434900)~~

摘　　要：前视合成孔径雷达(SAR)成像存在多普勒左右模糊的问题,需要利用空域资源进行解模糊处理。限于无人机(UAV)的载重与尺寸,接收阵列通常较小,解多普勒模糊的空域波束形成能力不足。此外,前视SAR回波方位多普勒梯度小、带宽窄,使得接收带宽未被充分利用。基于以上问题,该文提出多普勒分集前视SAR成像方法。该算法在前视SAR成像技术的基础上,利用多普勒分集MIMO技术,将多普勒窄带前视回波调制于不同多普勒中心以达到充分利用多普勒接收带宽的目的。进而,可获得一个数倍于真实接收阵列孔径的虚拟接收阵列,极大地扩展了接收通道,有效地改善了前视SAR成像解多普勒左右模糊的性能。Forward-looking Synthetic Aperture Radar(SAR)imaging has the problem of left-right Doppler ambiguity,so it is necessary to use spatial resources for ambiguity resolution.Due to the weight and size of Unmanned Aerial Vehicle(UAV),the receiving array is usually small,and the ability of spatial beam-forming for Doppler ambiguity resolution is insufficient.In addition,the small Doppler gradient and narrow bandwidth of forward-looking SAR echo make the receiving bandwidth underutilized.Based on the above problems,a Doppler diversity Multiple Input Multiple Output(MIMO)forward-looking SAR imaging method is proposed.Based on the forward-looking SAR imaging technology,the narrow-band forward-looking Doppler echo is modulated to different Doppler centers by using Doppler diversity MIMO technology to make full use of the Doppler receiving bandwidth.Furthermore,a virtual receiving array with several times the aperture of the real receiving array can be obtained,which expands greatly the receiving channel and improves effectively the performance of forward-looking SAR imaging in de-Doppler left-right ambiguity.

关 键 词：前视SAR成像 多输入多输出雷达 多普勒分集 自适应波束形成 

分 类 号：TN975[电子电信—信号与信息处理]