摘要
对采用方波频率调制的谐振型光纤陀螺(R-FOG)的闭环控制方案进行了分析。当光波频率偏离谐振中心频率时,R-FOG反射光强将出现方波强度调制信号,利用此误差信号可以实现R-FOG的闭环控制,将CW和CCW两束光的光波频率分别锁定为其谐振频率。两束光的闭环频率锁定分别通过激光器频率调节和频率偏置调制实现,锁定精度由控制系统的精度决定。对基于方波调制的闭环R-FOG的标度因子非线性进行了分析。分析表明,标度因子非线性受闭环频率控制精度的影响,影响的大小与谐振腔的谐振精细度相关。谐振精细度越高,频率控制精度的影响越大。对于50精细度的谐振腔,100 ppm的标度因子非线性要求频率控制精度优于1 113 Hz,而对于100精细度的谐振腔,对频率控制精度的要求提高为605 Hz。
The closed-loop control scheme of the resonator fiber optic gyro （R-FOG） based on square-wave frequency modulation is proposed. When the optical frequency drifts from the resonant center frequency, the reflection intensity of R-FOG becomes a square-wave intensity-modulated signal,from which the R-FOG can be closed-loop operated when the optical frequencies of clockwise （CW） and counter-clockwise （CCW） light beams are locked on the resonant frequencies. The closed-loop frequency locking is realized by adjusting the optical frequency of the laser and modulating the frequency offset,and the locking precision is decided by the precision of control system. The scale factor nonlinearity of a closed-loop R-FOG based on square-wave frequency modulation is analyzed. It is found that the nonlinearity depends on the precision of frequency control and the resonator fineness. For a resonator with 50 fineness,the nonlinearity of a hundred per million for scale factor requires the precision of frequency control better than 1 113 Hz,and for a resonator with 100 fineness,the precision of frequency control better than 605 Hz is required.
出处
《半导体光电》
EI
CAS
CSCD
北大核心
2006年第4期499-502,共4页
Semiconductor Optoelectronics
关键词
谐振型光纤陀螺
标度因子非线性
闭环
方波调制
resonator fiber optic gyro
nonlinearity of scale factor
closed-loop
squarewave frequency modulation
