基于液晶光学相控阵的空间激光通信PID跟踪方法

PID Tracking Method of Space Laser Communication Based on Liquid Crystal Optical Phased Array

液晶光学相控阵具备非机械光束偏转能力,将其应用到空间激光通信捕跟系统中,能够实现快速、灵活、多用户的接入。提出了一种基于液晶光学相控阵的快速跟踪方法,该方法采用电荷耦合器件(CCD)作为信标光探测器,比例积分微分(PID)闭环控制算法生成光束指向角控制点数据,实现对入射光束的捷变偏转,指向捕跟探测器中心,达到跟踪的目的。通过理论仿真可知PID闭环控制系统能够抑制高斯白噪声,跟踪精度小于6.5μrad。实验验证,经过10ms左右的调整,系统进入稳定跟踪状态,跟踪精度小于12.6μrad。

The liquid crystal optical phased array, which has the ability of deflecting non-mechanical beam, can be applied to space laser communications acquisition-tracking system to realize fast, flexible, and multiple-user access. A fast-tracking method based on liquid crystal optical phased array is presented, and the method uses charge coupled device （CCD） as a beacon light detector. Proportional integral differentiation （PID） closed-loop control algorithm is used to generate beam angle of direction control point data. Agile deflection of the incident light beam can be achieved, which points to the center of the acquisition-tracking detector, thus the purpose of tracking is achieved. The theoretical simulation shows that PID closed-loop control system can suppress Gaussian white noise and thetracking accuracy is less than 6.5μrad. Experimental results show that after around 10 ms adjustment, the system enters the state of steady tracking, and the tracking accuracy is less than 12.6 μrad.