基于改进Xception实现涡旋光束轨道角动量识别  

Recognition of Vortex Beam Orbital Angular Momentum Based on Improved Xception

作　　者：陈永豪 刘晓云[1] 蒋金洋 高思宇 刘颖 柴腾飞 姜月秋[2] CHEN Yonghao;LIU Xiaoyun;JIANG Jinyang;GAO Siyu;LIU Ying;CHAI Tengfei;JIANG Yueqiu(School of Science,Shenyang Ligong University,Shenyang 110159,China;Department of Development and Planning,Shenyang Ligong University,Shenyang 110159,China)

机构地区：[1]沈阳理工大学理学院,沈阳110159 [2]沈阳理工大学发展规划处,沈阳110159

出　　处：《光子学报》2024年第4期73-83,共11页Acta Photonica Sinica

基　　金：辽宁省教育厅基础研究项目(No.LJKMZ20220620);2023年中央引导地方科技发展资金(No.2023JH6/100100066)。

摘　　要：当光束在海洋中传输时,湍流的存在会严重影响光束的质量,导致接收端光场产生扭曲和退化现象。为解决该问题,提出一种基于改进深度可分离网络(IXception)的方法,用于实现通过海洋湍流传输的涡旋光束轨道角动量模态识别。采用分步相位屏的思想,基于功率谱反演法仿真涡旋光束在海洋中的传输过程,并建立入射光场发生的退化、扭曲的散斑场数据集,用数据集来训练IXception识别散斑场中涡旋光束的轨道角动量。IXception延用Xception架构思想,结合了残差结构和倒置残差结构,能够提取高度空间深度特征,减少网络结构参数的冗余,增强泛化能力。研究结果表明,IXception在20 m和80 m湍流中对扭曲光场轨道角动量的识别率达到了99.20%与97.9%。随着传输距离的增加,IXception的识别率会略有降低,但与Xception模型相比,IXception识别性能更好。As an emerging wireless communication technology,optical communication,which utilizes lasers as a means of information transmission,combining the advantages of high communication capacity and high-speed transmission,is gradually gaining widespread attention.Since Allen and others first demonstrated that optical vortices carry Orbital Angular Momentum(OAM)under near-axial conditions,vortex beams have attracted significant attention.OAM has infinitely many orthogonal eigenstates,forming an infinite-dimensional Hilbert space.Theoretically,this property can infinitely increase communication transmission capacity.Due to these unique characteristics,vortex beams find widespread applications in optical imaging,micro-operations,and free-space optical communication.However,when vortex beams propagate in the ocean,the presence of turbulence significantly affects the quality of the beam,leading to distortion and degradation of the light field at the receiving end.In recent years,scholars worldwide have proposed OAM recognition schemes under different conditions.Nevertheless,when vortex beams propagate in complex media such as oceanic turbulence,their OAM spectrum becomes broader,posing a challenge to OAM recognition.The lack of effective OAM detection methods hampers the development of oceanic optical communication.With the rise of artificial intelligence,deep learning technologies have rapidly developed in various fields.This paper proposes a method based on improved deep separable networks(IXception)that combines deep learning with traditional oceanic optical communication technology.This method aims to achieve OAM mode recognition of vortex beams transmitted through oceanic turbulence.Initially,the paper adopts the idea of stepwise phase screens based on the power spectrum inversion method to simulate the transmission process of vortex beams with different OAM values in the ocean.The corresponding dataset is established by collecting,degrading,and distorting the speckle field image at the receiving end.Subsequently,the d

关 键 词：涡旋光束 轨道角动量 海洋湍流 深度可分离网络 倒置残差结构 

分 类 号：O439[机械工程—光学工程]