基于单探测器电频标记算法的相干合成影响因子分析  

Influence Factor of Coherent Beam Combining Based on Single-Detector Electronic-Frequency Tagging

作　　者：刘贞 张永科[1] 沈琪皓[1] 何幸锴[1] 段良友 刘思吟 周鼎富[1] Liu Zhen;Zhang Yongke;Shen Qihao;He Xingkai;Duan Liangyou;Liu Siyin;Zhou Dingfu(Laser Application System Technology Department,Southwest Institute of Technical Physics,Chengdu 610041,Sichuan,China)

机构地区：[1]西南技术物理研究所激光应用系统技术部,四川成都610041

出　　处：《中国激光》2025年第2期209-216,共8页Chinese Journal of Lasers

基　　金：基础性军工科研院所稳定支持专项。

摘　　要：单探测器电频标记算法是一种基于正交解调确定误差信号的相位控制方法,在相干合成主动相位控制方面具有明显的优势。该算法主要包含调制信号频率、调制信号幅度、积分时间、反馈系数等可变参数,参数的选取对主动相位控制的精度和速度有很大的影响。首先分析了单探测器电频标记算法实现相干合成的基本原理,然后搭建了两路光纤相干合成系统,对单探测器电频标记算法参数的取值准则进行了实验研究,在实验中通过改变积分时间、调制信号幅值、调制信号频率、反馈系数及控制环路延时5项参数,总结了单探测器电频标记算法的参数选取准则。实验研究结果表明:为减小非整数倍积分时间对合成效果的影响,积分时间须为调制信号周期的10倍左右;调制信号幅值需要设置在一定范围内,才能够实现目标合成效率,并且积分时间越长,可取幅值的下限越低;调制信号频率越大,环路延时误差补偿的精度要求就越高,系统控制带宽也越大。反馈系数的选取需要考虑系统的阵列规模和相位噪声水平,平衡控制带宽和控相精度的矛盾,且正交解调信号和调制信号之间的延时应小于90°以避免控制系统失锁。Objective Coherent Doppler wind radars are widely used in aviation safety,climate modeling,and wind-farm-project optimization.As the demand for the radar detection range increases,the requirement for higher single-pulse energy in single-frequency lasers increases accordingly.However,in single-frequency fiber-pulsed amplifiers,energy improvement is significantly hindered by thermal effects and nonlinear effects in the fiber,such as stimulated Brillouin scattering.Using coherent beam-combining(CBC)technology,several fiber lasers can be combined to increase the output energy exponentially while maintaining the line width,beam quality,and polarization degree,as well as overcome the limited output energy of single-frequency fiber amplifiers.In CBC systems,achieving multibeam phase locking requires high-speed and precise phase control.In an active CBC system,the output-light phase of the combined beam is detected and a closed-loop feedback forms to correct the phase error,thus achieving phase locking for each sub beam.Single-detector electronic frequency is an active phase-control technology that uses orthogonal demodulation to obtain the error signal.The error signal,which is proportional to the phase difference between the measured beam and other beams,provides excellent phase-error correction for multibeam and high-power coherent combination systems.For the locking of optical coherence by single-detector electronic-frequency tagging(LOCSET)CBC system,parameter optimization is crucial for enhancing active phase control.Methods In this study,the principle of a single-detector electronic-frequency algorithm for achieving CBC was analyzed;subsequently,two optical-fiber CBC systems were constructed.The selection criteria for the single-detector electronic-frequency algorithm parameters were investigated experimentally.In the experiments,five parameters‒integration time,modulating signal amplitude,modulating signal frequency,feedback coefficient,and control loop delay‒were varied.The criteria for selecting the paramet

关 键 词：相干激光测风雷达 相干合成 单探测器电频标记法 主动相位控制 

分 类 号：O436[机械工程—光学工程]