谐振式光纤陀螺调相检测分析

谐振式光纤陀螺（R—FOG）是新一代惯性旋转传感器的代表。在陀螺系统中，信号检测系统占有非常重要的地位，其检测精度的大小直接影响陀螺的分辨率，而解调曲线的优化能够进一步提高检测系统的灵敏度。利用贝塞尔函数展开和光波场叠加的方法分析了谐振式光纤陀螺调相检测系统解调输出信号与谐振频率偏差之间的关系，系统采用的是带有铌酸锂相位调制器的相位谱检测技术。根据解调输出信号的解析表达式，通过数值计算，分析了解调曲线的变化规律，得到了施加在铌酸锂相位调制器上调制波形的最佳调制系数和相应的最佳调制频率范围，并进一步用实验系统验证了上述分析结果。

Analysis on Phase Modulation Spectroscopy of Resonator Fiber Optic Gyro

Resonator fiber optic gyro(R-FOG) is a promising candidate for the next generation inertial rotation sensor.The signal detection system is very important in the R-FOG.The detection precision influences the ultimate resolution of the gyro directly.Optimization of the demodulation curve can enhance the detection resolution.Therefore,it has significance to optimize the demodulation curve.By the use of expansion of Bessel function and optical field overlapping method,the relation between the demodulation curve and the resonant frequency deviation was analyzed.According to the analytical expression of the demodulation curve in this phase modulation spectroscopy scheme,the changing rule for the curve was analyzed by the numerical method.Then optimized values for the modulation frequency and modulation index were obtained.The experiments verified the analytical results.