谐振式微光学陀螺(RMOG)中,方波频率调制的三角波实现形式消除了双频率锯齿波中复位时间与复位误差引起的输出光强波动。理论分析了三角波实现方波频率调制的过程中波形转折点引起非连续频率调制对输出光强的影响。仿真分析了不同调制频率偏置下调制波形转折点以及不同激光频率与谐振频率偏差对输出的影响。利用时域梳状滤波器对输出信号进行滤波,以消除非连续频率调制引起的输出脉冲噪声对陀螺检测精度的影响。最后,实验验证了实际RMOG系统非连续频率调制对应的输出脉冲噪声,并比较了采用时域梳状滤波之后陀螺输出性能的改善情况。实验测试结果表明,10min测试时间内陀螺偏置稳定性从1.96。/s提高到0.11°/s。
Square-wave frequency modulation is widely used in resonator micro-optic gyro (RMOG). The triangle phase modulation waveform for the realization of square-wave frequency modulation eliminates the output fluctuation induced by the reset time and reset error in sawtooth modulation waveform. The influence on the output intensity by the turning points of triangle phase modulation waveform is ana- lyzed. Moreover,outputs under modulation waveforms with different frequency bases and different rota tion rates are theoretically calculated. Furthermore,the pectinate filter is involved to avoid the output error induced by the discontinuous frequency-modulation. Finally, the influence of the discontinuous frequency modulation is observed in ROMG experimental setup, and the pectinate filter greatly improves the gyro bias stability from 1.96°/s to 0. 11°/s.