双环形腔复合瑞利后向散射式光纤转动传感特性

基于A.Kung等所提出的后向瑞利(Rayleigh)散射式光纤转动传感原理,提出了一种双环形腔复合的Rayleigh后向散射式光纤转动传感器(RBFORS)新结构.利用两个2×2单模光纤耦合器,建立了复合双环形腔Rayleigh后向散射式光纤转动传感器的理论模型.通过计算机仿真,给出了用光时域反射计(OTDR)探测到的光纤转动传感器输出信号的特性,利用优化的环长和分光比两结构参量,分析了模拟结果.选择双环的长度分别为1500 m和1078 m,2×2光纤耦合器的耦合系数分别为95.23%和94.88%构建了测试系统,对不同转速所探测到的Rayleigh后向散射信号进行测量,得到了实验结论与理论相一致的结果.双环的采用,提高了测量信号的强度,增加了测试的有效数据,使其更有利于识别,提高了转速测量的精度.

Characteristic of Compound Two-Ring Combined Rayleigh Backscattering Fiber Optic Rotation Sensing

A novel compound two-ring combined Rayleigh backscattering fiber optic rotation sensor (RBFORS) is demonstrated and simulated based on the working principle given by A. Kung. The theoretical model of the two-ring resonators combined RBFORS is established by using two 2×2 fiber star couplers. The output signal characteristics of optical time domain reflectometer (OTDR) are deduced and analyzed by optimizing the structure parameters of the two rings cavity lengths and coupling ratios. The experiment system is constructed by the two-ring with the lengthes of L1=1500 m and L2=1078 m and fiber couplers with the coupling ratios of k1=95.23% and k2=94.88%, respectively. The Rayleigh backscattering signals are measured at different rotation rates. The experimental results are agreement with the theoretical prediction. The measurement intensity is increased by utilizing the compound two-ring structure. Therefore, the valid data number is increased, which is helpful to identify and enhance the precision of the measurement rotation rate.