使用区域中值滤波算法降低同步辐射红外线站由Top-Up模式引入的噪声  

Elimination technology of noise introduced by top-up injection in synchrotron radiation infrared beamline

作　　者：朱化春[1] 佟亚军[1] 吉特[1] 彭蔚蔚[1] 陈敏[1] 肖体乔[1] ZHU Hua-Chun;TONG Ya-Jun;JI Te;PENG Wei-Wei;CHEN Min;XIAO Ti-Qiao(SSRF,Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201204,China)

机构地区：[1]中国科学院上海应用物理研究所上海光源,上海201204

出　　处：《红外与毫米波学报》2018年第2期251-256,共6页Journal of Infrared and Millimeter Waves

基　　金：国家自然科学基金青年科学基金(11405258;11605281;11505267);国家自然科学基金(11475252;31300480);上海市自然科学基金(15ZR1448200;15ZR1448900)~~

摘　　要：为了提高同步辐射红外光源的光子通量和亮度以及改善光学元件的热稳定性,同步辐射光源现多采用恒流注束(Top-Up)模式,以保持储存环内部束流的稳定.在增强器向储存环注束时,储存环电流的瞬时起伏及电子束团位置的变动等会使同步辐射红外线站所用红外傅立叶变换(FTIR)光谱仪所采的干涉图上出现较大的波动,形成噪声;本文根据该噪声的特点,以及全域中值滤波算法处理该类型的噪声的不足,提出使用区域中值滤波算法对红外谱学线站使用的FTIR光谱仪所采的干涉图进行预处理,以消除由Top-Up模式引入的噪声的影响;并根据该型噪声的特点和区域中值滤波算法的处理过程,设计了一套去除由Top-Up模式引入的同步辐射红外谱学噪声的流程,使该区域中值滤波算法的处理过程无需人工干预;使用该区域中值滤波算法对具有该型噪声的干涉图进行了降噪处理,计算结果表明:使用该滤波算法可消除由Top-Up模式引入噪声的影响,提升Top-Up模式下所采光谱的信噪比.In order to enhance the photon flux and brightness of a synchrotron source,and improve the thermal stability of optical elements,synchrotron radiation source often operates in the qusi-constant current injection(Top-Up)mode.The Top-Up mode can maintain a stable beam current in the storage ring of Synchrotron Source.When the electron is injected into the storage ring from the booster,a noise induced by the instantaneous fluctuation of the beam current in the storage ring will cause a large fluctuation on the interferogram,which can be observed by the FTIR spectrometer used in IR experimental endstation.The median filtering algorithm is not sufficient to filter the noise according to the noise characteristics.Therefore,a zone median filter method is proposed to eliminate the noise introduced by the Top-Up mode.A set of the processes of zone median filtering algorithm is designed,which can eliminate the Top-Up mode induced noise on the interferogram automatically.Simulation results show that:the filtering algorithm can be applied to eliminate the noise on the interferogram introduced by the Top-Up mode effectively,so the method can be used to enhance the spectral SNR of the spectrum in the Top-Up mode.

关 键 词：同步辐射红外光源 恒流注束 噪声消除技术 区域中值滤波 

分 类 号：O436[机械工程—光学工程]