基于载波调制的光纤振动传感复用系统

Fiber vibration sensing system multiplexed by carrier modulation

提出了一种基于载波调制的光纤振动传感复用系统,其优点在于,对于感应外界扰动的不同感应光纤单元产生的干涉信号用不同频率的载波进行调制,相邻载波频率之间的频率差无需大于外界扰动引起的信号基波频率上限的两倍。各光纤感应单元形成的信号被共同的光电探测器检测后,利用信号基波来分析扰动信号的物理量,利用载波基波或谐波的边带判断感应扰动信号的光纤。

A fiber vibration sensing system multiplexed by carrier modulation was proposed.The advantage of the system was using carrier of different frequency to modulate the interference signal of different sensor unit.The difference of the adjacent frequency was not acquired to be two sizes of the first harmonic frequency of the disturbed signal.After the signals formed by different fiber sensor unit were detected by the same photoelectric detector,the system used the first harmonic to analyze the disturbed signal and the sideband of the first harmonic or harmonic of the carrier was used to decide the fiber which senses the disturbed signal.