摘要
针对无线光通信存在光束对准耗时长的问题,提出一种发射端采用图像跟踪,接收端采用二维反射镜控制的光束快速对准方法。依据几何光学理论计算了激光经二维反射镜后出射的扫描轨迹,并在无线光通信强度调制/直接检测系统上开展实验。实验结果表明:当通信距离为1.3km时,光斑型心在x(y)方向的方差由跟踪前的12.5734pixel^(2)(5.1393pixel^(2))降至跟踪后的2.2770pixel^(2)(1.3697pixel^(2)),探测器输出电信号的幅值为92.4mV;当通信距离为10.3km时,光斑型心在x(y)方向的方差由跟踪前的18.8653pixel^(2)(10.5290pixel^(2))降至跟踪后的14.4970pixel^(2)(8.0287pixel^(2)),探测器输出电信号的幅值为74.4mV。所提方法无需将控制信号由接收端回传至发射端,在快速建立下行链路的同时即可实现上行链路的建立。
Objective When the laser signal is transmitted through the atmospheric channel,the fluctuation of atmospheric refractive index caused by atmospheric turbulence causes beam expansion,beam drift,and wavefront distortion,which harms the reception of the optical signal and even leads to the interruption of communication in severe cases.In a wireless optical communication system,the gaze-gaze,gaze-scan,and skip-scan are used to achieve the coaxial alignment of the beam between the transmitting and receiving antennas,which increases the preparation time of system communication.In practice,a fast acquisition,tracking,and alignment mechanism must establish links.The wireless optical communication system’s coaxial alignment demands that the optical axis of the transmitting and receiving antennas completely coincide in space.The detector must return the measured parameter data to adjust the transmitting antenna to keep the beam stable coarse alignment for a long time and fine alignment on this basis.Atmospheric turbulence affects long-distance data return and position adjustment,making the traditional long-axis beam alignment process uncertain.In this paper,an acquisition tracking and pointing system with independent transceiver control is developed.The transmitter calibrates and tracks the target position by the calibration camera to realize the course alignment of the beam;at the receiving end,a two-dimensional mirror is used to control the position as the spot center feedback,suppress the atmospheric turbulence,and realize the fine alignment of the beam.The non-common sight axis control avoids the inconvenience of transmitting control instructions from the receiving end to the transmitting end,and it is not necessary to use a space stable platform for the moving base,which greatly facilitates the promotion of wireless optical communication.Methods Fig.1(b)shows the wireless optical communication using a two-dimensional mirror-assisted alignment.The system comprises the calibration coarse alignment from the transmittin
作者
杨尚君
柯熙政
吴加丽
刘旭光
Yang Shangjun;Ke Xizheng;Wu Jiali;Liu Xuguang(School of Automation and Information Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi,China;Shaanxi Civil-Military Integration Key Laboratory of Intelligence Collaborative Networks,Xi’an 710048,Shaanxi,China;School of Physics and Telecommunications Engineering,Shaanxi University of Technology,Hanzhong 723001,Shaanxi,China;Department of Communication Engineering,School of Automation and Information Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2022年第11期95-108,共14页
Chinese Journal of Lasers
基金
陕西省科研计划项目(18JK0341)
陕西省重点产业创新项目(2017ZDCXL-GY-06-01)
西安市科技计划项目(2020KJRC0083)。
关键词
光通信
光束扫描
捕获跟踪对准
二维反射镜
optical communications
beam scanning
acquisition tracking alignment
two-dimensional mirror
