微波光子SAR最优子带融合的全分辨伪彩图生成方法  

Optimal Sub-band Selection Algorithm for Pseudo-color Image Synthesis in Microwave Photonic SAR

作　　者：海宇 刘玲 李中余 蒲巍 王晓婷 武俊杰 李王哲 李若明 黄钰林 杨建宇 HAI Yu;LIU Ling;LI Zhongyu;PU Wei;WANG Xiaoting;WU Junjie;LI Wangzhe;LI Ruoming;HUANG Yulin;YANG Jianyu(School of Information and Communication Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China;Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China;The National Key Laboratory of Microwave Imaging Technology,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]电子科技大学信息与通信工程学院,成都611731 [2]中国科学院空天信息创新研究院,北京100094 [3]中国科学院空天信息创新研究院微波成像技术重点实验室,北京100190

出　　处：《雷达学报（中英文）》2024年第2期485-499,共15页Journal of Radars

基　　金：国家自然科学基金(62171084,61922023,62101096);电子信息控制重点实验室开放基金。

摘　　要：微波光子(MWP)雷达是一种通过光子器件对传统微波雷达硬件架构进行改进的新型雷达系统。借助光子器件卓越的物理特性,MWP雷达能够发射超宽带、高线性度的高质量线性调频信号,从而实现对目标的超高分辨率探测与成像。在目标成像与探测过程中,不同结构和特性的目标区域对不同频率信号的响应存在差异。因此,微波光子雷达具备通过散射差异生成伪彩图像的潜力,从而进一步提升微波光子合成孔径雷达(MWP-SAR)的信息获取能力。传统的遥感技术生成的伪彩图像分辨率较低,无法达到厘米级的分辨。因此,该文提出了一种在保证MWP-SAR高分辨率的前提下合成伪彩图像的方法。该算法首先建立了最优子带回波搜索模型,随后采用最优子带搜索算法对超宽带回波进行处理,以获取散射特性相差最大的子带回波通道。再对多子带差异图像进行色彩合成,通过这一处理步骤,能够生成对目标散射特性最佳描述的伪彩图像。同时,为了确保MWP-SAR的分辨率不受到损失,建立了一个融合模型,将全分辨率的SAR图像与多子带图像相融合,以维持伪彩图像的高分辨率。最终,通过实测的机载MWP-SAR数据成功地合成了全分辨率的伪彩色图像,从而验证了该算法的有效性。该算法可以使得MWP-SAR在成像时获取更多的目标信息,为成像雷达微波视觉的实现提供辅助。Microwave Photonic(MWP)radars have remarkably improved traditional microwave radar hardware architectures using photonics devices.With the exceptional physical properties of photonic devices,MWP radars can emit ultra-wideband,high-linearity,high-quality linear frequency modulation signals,allowing ultra-high-resolution target imaging and detection.Different target regions exhibit distinct responses to different frequency signals during target imaging and detection due to their diverse structures and characteristics.Therefore,MWP radars have the potential to generate pseudo-color images based on scattering differences,further enhancing the information retrieval capability of MWP Synthetic Aperture Radar(MWP-SAR).Pseudo-color images generated using traditional remote sensing techniques cannot achieve centimeter-level resolution.Therefore,we propose a method for generating pseudo-color images while maintaining the resolution of MWP-SAR.The algorithm first determines an optimal sub-band echo search model and subsequently employs the optimal sub-band search algorithm to process the ultra-wideband echoes to obtain sub-band echo channels with the largest scattering characteristic differences.The multi-sub-band images are then color-composited to generate pseudo-color images that best describe the target scattering characteristics.However,to ensure the high resolution of MWP-SAR,a fusion model is established to combine the full-resolution SAR image with the multi-sub-band image.Finally,full-resolution pseudo-color images are successfully synthesized using the measured airborne MWP-SAR data,validating the effectiveness of the algorithm.This algorithm enables MWP-SAR to obtain more target information during imaging,offering assistance in implementing imaging radar and microwave vision.

关 键 词：微波光子(MWP) 合成孔径雷达(SAR) 伪彩色图像 目标散射特性 最优子带 

分 类 号：TN957[电子电信—信号与信息处理]