谐振型光纤陀螺克尔效应误差消除方法研究

Study on Kerr-Effect-Induced Bias Reduction Method for Resonator Fiber Optic Gyroscope

对采用方波频率调制数字闭环谐振型光纤陀螺中克尔效应的影响进行了深入的理论分析.分析表明,由克尔效应引起的陀螺误差不仅与光纤环内两相反方向光束的光强差有关,而且还依赖于两路光波频率调制的调制幅度.通过适当调节两光束的频率调制幅度,可有效地实现克尔效应误差的消除.这种基于方波频率调制的克尔效应误差消除方法利用了方波调制的特点,通过调节调制幅度实现误差消除,无需额外光学元件,对强度调制器调制频率要求低,是数字谐振型光纤陀螺系统中消除克尔效应误差的有效方法.

The influence of Kerr effect to close-loop digital resonator fiber optic gyroscope based on squarewave frequency modulation was analyzed in theory. The results show that the Kerr-effect-induced bias relates to the light intensity difference between two inverse lightwaves, and the amplitudes of square-wave frequency modulation of these inverse lightwaves also affect it. Through proper adjustment to frequency modulation amplitude, the Kerr-effect-induced bias can be effectively reduced. This method for Kerreffect-induced bias reduction utilizing the characteristic of square-wave frequency modulation, need without any additional optical devices, has low intensity modulation frequency requirement. And it is a effective method for Kerr-effect-induced bias reduction in close-loop digital R-FOG.