瑞利BOTDA系统中电光调制器的优化设计

Optimization of Electro-Optic Modulator for Rayleigh-Brillouin Optical Time-Domain Analysis System

单端布里渊光时域分析系统可以实现单端入射,测量断裂光纤的传感信息,适用于大范围监测场合。基于瑞利散射的布里渊光时域分析系统通过从光纤同一端入射脉冲光和连续光来实现单端测量。为了得到频率单一的脉冲光和连续光,提出采用两个电光调制器并联结构产生含脉冲基底的脉冲光,讨论了电光调制器的最佳工作点设置。研究证明,该设计能够产生系统所需的一阶双边带基底连续光和0阶脉冲光,克服了单个电光调制器调制时受到多种光分量干扰的问题,同时降低了对电光调制器的要求。

Single-ended Brillouin optical time domain analysis system can work in single-ended and measure the sensor informa-tion of the broken fiber, which is suitable for large-scale monitoring occasions. The Brillouin Optical Time-Domain Analysissystem based on Rayleigh scattering （RBOTDA） realizessingle-ended sensing by impinging pulsed light and pulsed continuouslight from the same end of the fiber. The Electro-Optic Modulator （EOM） is used to generate pulsed light and the pulsed sub-strate is the key technique of RBOTDA system. In order to get pulse light and continuous light in single frequency, two parallelEOM structure is proposed to generate the pulsed light for the RBOTDA system and the optimal operating point of the electro-optical modulator is discussed in this paper. It is proved that the design can produce the first-order double-side baseband contin-uous light and zero-order pulsed light. The proposed design overcomes the interference with single EOM, and reduces the re-quirements of EOM.