谐振式微光学陀螺偏置频率调制技术研究

Bias-frequency-modulation used in resonator micro-optic gyro

谐振式微光学陀螺(RMOG)是一种基于光学Sagnac效应的新型角速度传感器。提出了基于模拟波形连续线性相位调制技术的偏置频率调制。与传统的双频率锯齿波调制以及数字调制方法相比,偏置频率调制消除了由于锯齿波回扫或数字波形中的台阶效应引入的脉冲噪声。从理论上推导了连续线性相位调制波形参数与陀螺的动态范围和灵敏度的关系,得出波形参数的选取原则。实验采用自由谱宽、谐振清晰度分别为1.6GHz和60的集成光学谐振腔陀螺构建RMOG系统,得到1h陀螺零偏稳定性1.06×10-3rad/s、±500°/s动态范围内陀螺输出非线性度小于1%。

Resonator Micro-Optic Gyro （RMOG）, based on Sagnac effect, is one of the new rotation-rate sensing devices. Bias-frequency-modulation （BFM） induced by analog continuous linear phase modulation technique is presented in RMOG. Compared with the traditional serrodyne phase modulation or digital phase modulation methods, the proposed modulation technique has the intrinsic advantage in free of sweeping-hack or step-effect, eliminating the pulse noise induced by the discontinuous waveform. The influence on dynamic range and resolution of the RMOG by the modulation waveform parameters is theoretically analyzed. Experiments are carried out on the RMOG composed of integrated optic resonator with free spectral range （FSR） and fitness （F） of 1. 6GHz and 60, respectively. Dynamic range of ±500°/s with nonlinearity of less than 1 %, and bias drift of 1.06×10^-3ad/s with integration time of ls over lh are obtained.