谐振式光纤陀螺的误差及噪声分析

谐振式光纤陀螺(Resonator Fiber Optic Gyroscope,RFOG)的性能是多种误差和噪声共同作用的结果。分析了RFOG主要误差与噪声的产生机理,建立了各误差与噪声的分析模型,结合具体陀螺参数,对误差和噪声的等效旋转速率进行了估算,对抑制误差和噪声的有关措施进行了数值量化。以RFOG零偏稳定性0.1°/h需求为例,为抑制背向散射噪声及背向反射误差,相位调制移频时顺时针和逆时针光波的载波强度残留水平之积需高于112dB;为抑制克尔效应,顺时针和逆时针方向的光强差需控制在3.86nW以内;地磁场方向不确定性引起的陀螺零偏稳定性约为0.7°/h。该工作为RFOG实验研究和工程设计提供了理论指导。

Analysis on Error and Noise of Resonant Fiber Optic Gyros

The generating mechanisms of the main errors and noises of resonaor fiber optica gyroscope (RFOG) are analyzed, and the analyzing models are established. Combining with specific gyroscope parameters, the equivalent angular velocities of the errors and noises are estimated, and the relevant restraint measures are quantified. Taking bias stability of 0.1°/h in the RFOG as an example, to suppress the backscattering noise and the back reflection error, the requirement of the carrier suppression level should be as high as 112dB, and to suppress the Kerr effect, the light intensity difference between CW and CCW should be controlled at 3.86nW or less. The gyro bias stability caused by the uncertainty of the earth magnetic field direction is about 0.7°/h.