摘要
基于光纤陀螺的调制-解调原理,讨论了调制方波的频率、相位、占空比和光纤环特征频率对方波调制误差的影响,推导出方波调制误差的数学模型。测量光纤环特征频率、调制方波频率、相位及其温度系数,分析了温度变化对方波调制误差的影响。提出了数字时域梳状滤波的解调方法,推导出消除方波调制误差的条件表达式。实验结果显示,数字时域梳状滤波可以使方波调制误差引起的偏置漂移减小到0.3°/h以下。
Based on the principle of square wave modulation and demodulation in fiber optic gyroscope（FOG）, the effects of the square wave frequency,phase and duty cycle and the fiber coil eigenfrequency upon square wave modulation errors were discussed. The temperature coefficients of the fiber coil eigenfrequency and square wave frequency,duty cycle and phase were measured by using a lock-in amplifier. The bias drift of FOG due to the square wave modulation errors was analyzed at dif- ferent temperatures. A digital time-donmain comb filter was presented and a conditional expression was derived to eliminate the square wave modulation errors steadily. The test results show that the bias drift,brought by square wave modulation errors,is reduced to less than 0.3°/h by applying digital time-domain comb filter in FOG.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2008年第4期430-433,共4页
Journal of Optoelectronics·Laser
基金
国家"863"计划资助项目(2007AA04Z436)
关键词
光纤陀螺
调制误差
调制
解调
梳状滤波
fiber optic gyroscope（FOG）
modulation errors
modulation
demodulation
comb filter
