报道了一种用于布里渊分布式光纤传感器(DOFS)的高稳定光学锁频系统。一台波长为1550nm的半导体分布反馈(DFB)激光器作为主激光器用于光纤传感探测,另一台同样的激光器作为从激光器,采用光学锁相的方法将其与主激光器进行频率跟踪,使主激光器与从激光器频率差恒定为11GHz。利用该光源搭建基于自发布里渊的分布式光纤传感系统(BOTDR),可以有效地实现宽带移频,使得探测解调频率降低到百兆赫兹量级,大大降低了探测的噪声,并且降低了BOTDR系统成本。结果表明,采用此光源方案的频率波动范围为±1MHz。
A high frequency-stable laser source for Brillouin distributed optical fiber sensor (DOFS) is reported. A distributed-feedback (DFB) laser is used as the maser laser for optical fiber sensor measurement. Another DFB laser is used as the slave laser of which the frequency is tracked with the master laser. Thus the frequency difference of the two lasers can be locked at 11 GHz. With this source for distributed optical fiber sensing applications, the frequency of the beat frequency signal is only several million hertz. As a result, the noise can be decreased and the cost of the equipment will be reduced. The results indicate that the range of freeuencv is ± MHz.