中文摘要：

针对布里渊光时域反射型（BOTDR）分布式光纤传感系统中脉冲光源消光比易受偏置电压漂移影响的问题,本文提出了一种结合双电极串联结构电光调制器（EOM）及＂扫描？步进跟踪＂算法的脉冲光源消光比自动控制方法。实验结果表明,该方法可将EOM输出脉冲光的消光比稳定在50 d B以上。在150 min的测试时间里,输出脉冲光消光比的最大值为52.4 d B,最小值为51.1 d B,波动值仅为1.3 d B。该方法对BOTDR光纤传感系统及高功率激光驱动装置等设备中脉冲光源性能的提升具有重要意义。

英文摘要：

A novel method to control the pulsed light extinction ratio automatically, which combines a double electrode series structure EOM with ＂scanning step-tracking＂ algorithm, is proposed. It aims to address the problem that extinction ratio of pulsed light is affected by bias voltage shifting in a Brillouin Optical-fiber Time-domain Reflectometry（BOTDR） based on distributed optical fiber sensing system. Based on the method, some experiments are conducted and important conclusions are deduced. The results show that it could keep the extinction ratio of pulsed light above 50 d B steadily. The fluctuation of extinction ratio is only 1.3 d B, maximum value of extinction ratio is 52.4 d B and the minimum value is 51.1 d B. It is indicated that the proposed method will have important significance for enhancing the performance of pulsed light source in BOTDR optical fiber sensing system and high power laser driving device.