基于多图超分辨率重建的精细导星仪星点质心定位精度提升方法  

A Precision improvement method of star centroid positioning based on multi-image super-resolution reconstruction for fine guide sensor

作　　者：王雯蕊 张泉 高源蓬[1,2,3] 房陈岩 尹达一 Wang Wenrui;Zhang Quan;Gao Yuanpeng;Fang Chenyan;Yin Dayi(Shanghai Institute of Technical Physics,Chinese Academy of Sciences,Shanghai 200083,China;Key Labray Infrared System Detection and Imaging Technology,Chinese Academy of Sciences,Shanghai 200083,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海技术物理研究所,上海200083 [2]中国科学院红外探测与成像技术重点实验室,上海200083 [3]中国科学院大学,北京100049

出　　处：《仪器仪表学报》2024年第3期306-314,共9页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(12103075)项目资助。

摘　　要：精细导星仪的星点质心定位精度决定了空间天文望远镜的视轴姿态解算精度,为了提升精细导星仪的星点质心定位精度,提出了一种基于深度小波循环神经网络的星图超分辨率重建方法。首先,借助微扫描技术获取亚像素错位低分辨率星图序列,采用小波编码器提取低分辨率星图的小波域特征,通过小波系数约束低分辨率星图的噪声,并将亚像素错位星图序列配准过程融入到网络学习中。其次,利用卷积门循环神经单元对所提取的多星图序列特征进行融合。最后,使用逆小波解码器对多特征融合模块输出的小波域特征进行解码,从而实现基于低分辨率星图序列的去噪与超分辨率重建。实验结果表明,分别采用平方加权质心法求取原始星图和超分辨率重建后星图中的各星点的质心位置,相比于前者,后者的各星点平均质心定位精度和稳定度在X方向分别提升了64.76%和19.15%,在Y方向分别提升了75.35%和26.14%。The accuracy of the fine guide sensor′s star centroid positioning determines the accuracy of the visual axis attitude calculation of the space telescope.To improve the positioning accuracy of the star centroid of the fine guide sensor,a star image super-resolution reconstruction method based on the deep wavelet recurrent neural network is proposed.Firstly,the micro-scanning technology is used to obtain the sub-pixel misalignment low-resolution star image sequence,and the wavelet domain features of the low-resolution star image are extracted by using the wavelet encoder while the noise of the low-resolution star image is constrained by the wavelet coefficients.The registration process of the input star image sequence is integrated into the network learning.Secondly,the convolutional gate recurrent neural unit is used to fuse the features of the extracted star image sequence.Finally,the inverse wavelet decoder is utilized to decode the wavelet domain features output by the multi-feature fusion module.In this way,the de-noising and super-resolution reconstruction based on low-resolution star image sequences are realized.The experimental results show that the square-weighted centroid method is used to obtain the centroid positions of each star point in the original star image and the reconstructed star image with super-resolution.Compared with the former,the average centroid positioning accuracy and stability of each star point in the X direction are improved by 64.76%and 19.15%,respectively.In the Y direction,the accuracy and stability are improved by 75.35%and 26.14%,respectively.

关 键 词：精细导星仪 星点质心定位 超分辨率重建 小波信号处理 卷积门循环神经网络 

分 类 号：TH124[机械工程—机械设计及理论] TP391[自动化与计算机技术—计算机应用技术]