谐振式光纤陀螺(R-FOG)是基于Sagnac效应产生的谐振频率差来测量旋转角速率的一种新型光学传感器。信号检测技术和系统中存在的各种噪声对系统的检测精度有着重要的影响。基于调相谱检测技术的谐振式光纤陀螺系统中,除顺时针(CW)和逆时针(CCW)光路传播的光强不均匀会引入非互易相位差,使系统出现零漂外,顺时针和逆时针光路的调制系数也会引入系统零漂。光克尔效应引入的系统零漂与系统的真实旋转在测量时是无法区分的,因此成为主要的噪声之一。通过光波场叠加原理,推导得到调相谱检测方案下的谐振式光纤陀螺系统中,光克尔效应引起的系统零漂的解析表达式。依据光克尔效应产生的零漂不随陀螺转速的改变而变化,利用简单的开环系统,对光克尔效应引入的陀螺零漂进行了测试。

Resonator fiber optic gyro (R-FOG) is a novel optical sensor whose resonant frequency is changed due to the Sagnac effect. The detection technique and system noises affect the detection precision greatly. In the R-FOG based on the phase modulation spectroscopy technique, not only the optical power difference between the clockwise (CW) and counterclockwise (CCW) light waves induces the bias drift, but also the two different modulation indexes do. The bias drift caused by optical Kerr effect is indistinguishable from the rotational-induced Sagnac frequency shift. Using the optical field overlapping method, the analytical expression for the rotation-rate error due to the optical Kerr effect is derived. For the bias drift caused by the optical Kerr effect does not change with the rotation-rate, using a simple open-loop operation, the drift caused by the optical Kerr effect is observed in the gyro output curve.