基于截断加权Wirtinger Flow算法的旋转测速频移特性提升研究  

Research on Improving the Frequency Shift Characteristics of Rotational Velocity Measurement Based on Truncated Weighted Wirtinger Flow Algorithm

作　　者：王泓洋 张子静[1] 刘浩[1] 吕鑫冉 宋家宇 崔成帅 赵远[1] WANG Hongyang;ZHANG Zijing;LIU Hao;LYU Xinran;SONG Jiayu;CUI Chengshuai;ZHAO Yuan(School of Physics,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]哈尔滨工业大学物理学院,哈尔滨150001

出　　处：《光子学报》2025年第3期107-117,共11页Acta Photonica Sinica

基　　金：国家自然科学基金(No.62075049);中央高校基本科研业务费专项资金(Nos.FRFCU5710050722,FRFCU5770500522,FRFCU9803502223,FRFCU5770600723);黑龙江省自然科学基金优秀青年项目(No.YQ2024F012)。

摘　　要：在远距离目标旋转速度的探测中,涡旋光束容易受到随机变化的大气湍流的影响,造成光束的相位畸变和螺旋谱的弥散,引起目标旋转速度测量性能下降。针对这一问题,采用截断加权Wirtinger Flow(Truncated Weighted Wirtinger Flow,TWWF)算法,该算法在初始化阶段的截断规则中引入样本中值,采用加权梯度的权值调整策略,避免容易陷入局部最优解的问题,提升了算法对畸变涡旋光束的迭代补偿能力,光场和旋转多普勒频移特性指标得到显著提升。结果表明,当大气湍流强度C_(n)^(2)为1×10^(-14)m^(-2/3),纯度、RDS峰-最大杂峰比、测速精度等指标可达0.99,2.18,0.80 rad/s;当C_(n)^(2)为1×10^(-12)m^(-2/3),则可达0.74,2.09,0.83 rad/s,相位相对误差可达3×10^(-16)量级,展现了TWWF算法强大的补偿能力。此外,讨论了掩码数目、湍流强度、光场叠加态等因素对算法指标的影响。本研究拓宽了WF类型算法在湍流畸变补偿方向的应用,提供了一种改善涡旋光束的远距离转速测量性能的方法。In the remote detection of the rotational velocity of a target,the vortex beam is easily affected by the random atmospheric turbulence,which causes the phase distortion of the beam and the dispersion of OAM spectrum,resulting in the deterioration of the performance of rotational velocity measurement.Since Wirtinger flow algorithm was proposed,its remarkable feature is that it can complete iterative convergence without any prior information and only one input,without falling into local optimal solutions.Relevant studies have theoretically shown that Wirtinger Flow algorithm has the ability of high precision and absolute convergence to the global optimal solution.The current research has improved the performance of the algorithm by enhancing the traditional WF algorithm.However,the analysis of improving the rotational velocity measurement metrics through compensating the beam distortion in complex environments is still insufficient.To solve this problem,this work enhances the traditional WF algorithm by improving the initialization and gradient descent rules,and proposes Truncated Weighted Wirtinger Flow(TWWF)algorithm.In this algorithm,the median value of the sample is introduced into the truncation rule in the initialization stage to make the initial estimation closer to the global optimal.The weight adjustment strategy of the weighted gradient descent algorithm is used to calculate the weight coefficient according to the results of adjacent iterations,and the distorted vortex beam is compensated to improve the optical field and the rotating Doppler frequency shift characteristics.Firstly,a vortex light field recovery and rotation velocimeter performance improvement system based on TWWF algorithm is designed.The input is simplified into one path.The probe beam then passes through the coded aperture of a programmable LCD screen,simulating a coded diffraction pattern,and then the CCD measures the light intensity for algorithm calculation,and finally the generated compensated phase screen is loaded on the spatial li

关 键 词：涡旋光束 大气湍流 旋转多普勒效应 相位恢复算法 测速精度 

分 类 号：O439[机械工程—光学工程]