前视多通道SAR成像及阵列姿态误差补偿  

Forward-looking Multi-channel Synthetic Aperture Radar Imaging and Array Attitude Error Compensation

作　　者：王鑫硕 卢景月 孟智超 张磊 WANG Xinshuo;LU Jingyue;MENG Zhichao;ZHANG Lei(School of Electronics and Communication Engineering,Shenzhen Campus of Sun Yat-sen University,Shenzhen 518107,China;School of Computer Science and Technology,Xidian University,Xi’an 710071,China)

机构地区：[1]中山大学电子与通信工程学院,深圳518107 [2]西安电子科技大学计算机科学与技术学院,西安710071

出　　处：《雷达学报（中英文）》2023年第6期1155-1165,共11页Journal of Radars

基　　金：国家自然科学基金(62101603)。

摘　　要：针对前视合成孔径雷达(SAR)成像中的左右多普勒模糊问题,前视多通道SAR(FLMC-SAR)通过波束形成可实现多普勒解模糊成像。然而阵列偏角误差和时变姿态误差会导致目标的空时特性失配,进而影响左右多普勒解模糊成像的性能。该文提出了一种FLMC-SAR成像及阵列姿态误差补偿方法,首先建立了FLMC-SAR三维阵列偏角误差和时变平台姿态误差模型,分析了二维空时谱平面中目标的空时特性匹配机理,建立分析阵列姿态误差带来的空时特性失配在空时平面中的表征模型,然后基于误差的非左右空变特性,提出在BP函数中添加误差补偿相位统一补偿左右目标的阵列姿态误差。仿真实验证明所提方法可实现FLMC-SAR阵列姿态校正及误差补偿,提升了前视多普勒模糊抑制性能,保证了前视成像的方位分辨性能。To solve the problem of left-right Doppler ambiguity in forward-looking Synthetic Aperture Radar(SAR)imaging,Forward-Looking Multi-Channel SAR(FLMC-SAR)can achieve Doppler ambiguity resolving imaging through beamforming.However,array deviation angle and time-varying platform attitude errors lead to the mismatch between the space and time characteristics of a target,which affects the Doppler ambiguity resolving imaging performance.This study proposes an FLMC-SAR imaging and array attitude error compensation method.First,the three-dimensional FLMC-SAR array deviation-angle error and time-varying platform attitude error models are established.The mechanism of matching the spatiotemporal characteristics of targets in the two-dimensional spatiotemporal spectrum plane is analyzed.In addition,a representation model is established to study the spatiotemporal characteristics mismatch caused by the array attitude error in the spatiotemporal plane.Thereafter,based on the non-left-right spatial variation of the error,we propose a method of adding an error compensation phase to the back projection function to uniformly compensate the array attitude error of left-right symmetric targets.The results of simulation experiments show that the proposed method can achieve FLMC-SAR array attitude correction and error compensation,enhance the performance of forward-looking Doppler ambiguity suppression,and ensure the azimuth resolution performance of forward-looking imaging.

关 键 词：前视多通道SAR(FLMC-SAR) 前视成像 阵列姿态误差 多普勒解模糊 方位分辨 

分 类 号：TN957.52[电子电信—信号与信息处理]