光纤陀螺光纤环分布偏振耦合误差预估

Estimation of Distributed Polarization Coupling Error in Optical Fiber Coil of Fiber Optic Gyroscope

分析了由光相干域偏振计测得的光纤陀螺保偏光纤环(PMFC)分布偏振耦合测试数据,建立了测量点偏振耦合幅度模型。结果表明,测试数据是实际偏振幅度耦合被宽谱光源相干函数调制的结果,且存在伪偏振耦合测试数据。在此基础上,提出并实现了分布偏振耦合数据处理算法。绕制PMFC,进行了不同温度条件下分布偏振耦合测试,并提取了真耦合位置和强度信息。通过建立PMFC二次偏振耦合误差预估模型,对不同温度下光纤环分布偏振耦合引起的光纤陀螺零漂误差进行了计算预估。利用高精度保偏光纤环分析测试仪对该环进行了对应温度的光纤陀螺零漂测试,零漂预估值与实测结果一致。

The distributed polarization coupling data measured by optical coherence domain polarizer in polarization maintaining optical fiber coil（PMFC）of fiber optic gyroscope is analyzed,and a polarization coupling amplitude model of measurement point is established.It is found that the polarization amplitude coupling is modulated by broadband source coherence function,and there exists pseudo polarization coupling measurement data.Based on this,a data processing algorithm for distributed polarization coupling data is proposed and implemented.PMFC is fabricated to conduct distributed polarization coupling tests at different temperatures,and the true coupling position and intensity information are extracted.The estimation model of secondary polarization coupling error of PMFC is established,and the bias drift error of fiber optic gyroscope induced by the distributed polarization coupling in fiber coil at different temperatures is estimated.With a high precision polarization maintaining fiber coil analyzer,the bias drift of fiber coil gyroscope is measured at corresponding temperature experimentally.The estimated results agree with the experimental results well.