中文摘要：

为了改善瑞利后向散射式光纤转动传感器测量转速的精度，基于单环瑞利后向散射式光纤转动传感原理，提出了一种新型的三环形腔复合光纤转动测量方法．该新结构利用4个2×2单模光纤耦合器，建立了复合三环形腔瑞利后向散射式光纤转动测量的理论模型．在给出用光时域反射计探测到的光纤转动传感器输出信号特性的同时，建立了分光比和环形腔长两参量的优化方法．依据参量优化后的模拟结果，选择长度分别为1500、1078、680m的光纤环形腔，耦合系数分别为95．23％、94．88％、95．26％和95．01％的光纤耦合器构建了测试系统，对不同转速所探测到的瑞利后向散射信号进行测量，验证了系统的可行性．采用复合三环，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，提高了测量转速的精度．

英文摘要：

In order to improve the accuracy of Rayleigh backscattering fiber optic rotational velocity meas- urements a novel three-ring combined fiber optic rotational measurement approach was proposed and simulated. It was based on the single ring scheme and the theoretical model of the three-ring resonator was established using four 2 × 2 fiber star couplers. The output signal characteristics were deduced and analyzed by optimizing the structural parameters of the three-ring cavity lengths and coupling ratios. The setup of the experimental system was based on the simulation＇s optimizing results, with L1 =1 500 m, L2 =1 078 m and L3 =680 m at coupling ratios k1 =95.23%, k2 =94.88%, k3 =95. 26% and k4 =95.01% respectively. The Rayleigh backscattering signals were measured at different rotational rates. The feasibility of the system was verified. Measured signals were intensified by utilizing the compound three-ring structure. Therefore, the number of valid data increases, which helps identification and enhances the precision of measurements of rotational rate.