针对星载积分路径差分吸收(IPDA)激光雷达的应用需求,研制了一套利用空芯光子晶体光纤(HC-PCF)作为吸收池,以CO2气体1.57μm处的吸收线作为频率参考,基于频率调制光谱稳频技术的激光稳频系统。结合其工作原理,建立仿真模型,计算了CO2气压、光谱调制频率以及调制深度对稳频误差信号的影响,给出最优化的设计参数。并且与实验测试数据进行了比对,实验数据与计算结果吻合。报道了系统的稳频效果,给出进一步提升稳频性能的方案意见。
A laser frequency stabilization system for the space integrated path differential absorption (IPDA) lidar is developed. The gas cell is made of the hollow-core photonics crystal fiber (PCF) filled with the CO2 and the absorption line around 1.57 μm is used as the laser frequency reference. The frequency modulation spectroscopy technique is used to stabilize the laser frequency. The impact of the pressure of CO2, the modulation frequency and depth on the error signal's slope is simulated, and the optimal parameters are given. The computed results are coincident with the measured results. At last, the performance of the laser frequency stabilization is shown, and the suggestion for further improvement is given.