基于数字闭环控制的光锁相环稳频技术研究
Research on Frequency Stabilization Technology of Opto-PLL Based on Digital Closed Loop Control

本文设计了一种基于声光移频器(AOFS)的光学锁相环系统，实现了DFB半导体激光器与窄线宽光纤激光器的频率锁定。系统采用高速数据采集卡获取主从激光器的相位与频率误差信号，并结合PID控制策略调节本振激光器。同时引入AOFS作为快速精密调谐元件，提升了系统的环路带宽和相位噪声抑制能力。本文首先从理论上分析了系统的工作原理，建立了包含噪声因素的仿真模型，并对锁相性能进行模拟验证。实验结果进一步证实了系统的有效性，显示出良好的频率稳定性和抗干扰能力。
In this paper, an optical phase-locked loop (PLL) system based on acousto-optic frequency shifter (AOFS) is designed to realize the frequency locking of DFB semiconductor laser and narrow linewidth fiber laser. The system uses a high-speed data acquisition card to obtain the phase and frequency error signals of the master-slave laser, and adjusts the local oscillator laser with PID control strategy. At the same time, AOFS is introduced as a fast precision tuning element to improve the loop bandwidth and phase noise suppression ability of the system. In this paper, the working principle of the system is analyzed theoretically, the simulation model including noise factor is established, and the phase-locked performance is simulated and verified. The experimental results further confirm the effectiveness of the system, showing good frequency stability and anti-interference ability.