中国激光, 2017, 44 (12): 1204002, 网络出版: 2017-12-11
基于锯齿波调制的光纤陀螺本征频率跟踪测量
Eigen Frequency Tracking Measurement of Fiber Optic Gyroscope Based on Sawtooth Wave Modulation
测量 光纤陀螺 本征频率 频率跟踪 相位调制 measurement fiber optic gyroscope eigen frequency frequency tracking phase modulation
摘要
为了实现快速且高精度的光纤陀螺(FOG)本征频率跟踪测量, 提出了一种基于锯齿波调制的本征频率跟踪方法。根据基于偶数倍本征频率锯齿波调制的光纤陀螺本征频率测量理论, 对相位调制器施加接近偶数倍本征频率的锯齿波调制信号,然后对光波进行相位调制,解调得出的误差信号强度反映锯齿波调制频率偏离偶数倍本征频率的程度。根据误差信号的强度调节锯齿波调制信号的频率, 使误差信号为零, 此时锯齿波信号的频率等于本征频率的偶数倍且方波偏置调制准确地处于本征频率上。实验结果表明, 该方法可以实现光纤陀螺本征频率的跟踪。与传统测量方法相比, 该方法具有快速、高精度等优点, 测量的精度优于1 Hz。
Abstract
To realize fast and high precision tracking measurement of fiber optic gyroscope (FOG) eigen frequency, a eigen frequency tracking method based on sawtooth wave modulation is proposed. Based on the eigen frequency measurement theory of fiber-optic gyroscope from even times eigen frequency sawtooth wave modulation, the sawtooth wave modulation signal with nearly even times eigen frequency is applied on the phase modulator, and phase of the wave is modulated. The demodulated error signal intensity represents the degree of sawtooth wave modulation frequency away from even times eigen frequency. The frequency of sawtooth wave modulation signal is modulated by the intensity of error signal, and the error signal is set to zero. At this time, the frequency of sawtooth wave signal is equal to even times eigen frequency, and the bias modulation of square wave is located at the eigen frequency exactly. The experiment results show that the proposed method can realize tracking of fiber-optic gyroscope eigen frequency. Compared with the traditional measurement method, the proposed method have the advantages of speediness and high precision. The accuracy of the measurement is better than 1 Hz.
王翔, 王夏霄, 于佳, 郑月, 王婷婷, 马福. 基于锯齿波调制的光纤陀螺本征频率跟踪测量[J]. 中国激光, 2017, 44(12): 1204002. Wang Xiang, Wang Xiaxiao, Yu Jia, Zheng Yue, Wang Tingting, Ma Fu. Eigen Frequency Tracking Measurement of Fiber Optic Gyroscope Based on Sawtooth Wave Modulation[J]. Chinese Journal of Lasers, 2017, 44(12): 1204002.