中文摘要：

开环光纤陀螺（FOG）常使用压电陶瓷（PZT）实现非互易性相位偏置,但相位调制中的非线性会造成工作点不稳定和Sagnac相位解调误差。本文对PZT二倍频调制和相位延迟导致的寄生调制信号进行了理论分析,进而提出在小角度Sagnac相移输入时利用二、四次谐波监控工作点,在Sagnac相移逐渐变大时利用一、三次谐波监控工作点;同时对比了相位延迟角为0°和90°所引起的工作点不稳定,采用较大相位延迟角可将工作点绝对误差降低到10-5水平,相位解调误差降低到10-5rad水平。

英文摘要：

The piezoelectric transducer（PZT） is often used to provide unreciprocal phase modulation in an open-loop fiber optic gyroscope（FOG）, but the non-linearities can affect the stability of work point and induce the Saganc phase error.In this paper, the spurious modulation signal output caused by the second harmonic phase modulation and phase delay is analyzed in theory.Numerical results demonstrate that it would be better choose the second and fourth harmonic components for the small Sagnac phase, while the first and to third harmonic components for the big Sagnac phase to demodulate the work point.By comparing the stabilities of work point at the zero degree and 90 degree of phase delay angle, a scheme to get stable work point is proposed.If a larger phase delay angle is adopted in the phase demodulation, the error of work point can be decreased to the magnitude of 10-5 order,and the phase demodulation error can be reduced to 10-5 rad.