一种三环并联Rayleigh后向散射式光纤转动传感器

以单环后向Rayleigh散射式光纤转动传感器原理为基础,提出了一种三环形腔并联Rayleigh后向散射式光纤转动传感器新结构.利用三个2×2单模光纤耦合器,建立了并联三环形腔Rayleigh后向散射式光纤转动传感器的理论模型,给出了用光时域反射计（OTDR）探测到的信号强度表达式.通过计算机仿真优化了参量,选择三环的长度分别为1 500 m、1 078 m和680 m.三个2×2光纤耦合器的耦合系数分别为95.23%、94.88%和95.26%构建了测试系统,对不同转速所探测到的后向Rayleigh散射信号进行测量,得到与理论相一致的实验结果.三环的采用,增加了测试的有效数据,使其更有利于识别,提高了测量转速的准确度.

A Combined Three-Ring in Parallel Rayleigh Backscattering Fiber Optic Rotation Sensor

A novel combined three-ring in parallel Rayleigh backscattering fiber optic rotation sensor (RBFORS) is proposed and simulated based on the single ring scheme.The theoretical model of the three-ring resonators combined RBFORS is established by using three 2×2 fiber star couplers.The expression of detection signal intensity by OTDR is deduced.The output signal characteristics are analyzed by optimizing the structure parameters of the three-ring cavity lengths and coupling ratios.The experiment system is constructed with L1=1 500 m,L2=1 078 m and L3=680 m at coupling ratios k1=95.23%,k2=94.88% and k3=95.26% respectively.Rayleigh backscattering signals are measured at different rotation rate.The experimental results are agreement with the theoretical prediction.The valid data number is increased by utilizing the three-ring in parallel combined RBFORS which is helpful to identify and enhance the precision of the rotation rate measurement.