调相谱检测技术下光纤环腔的谐振特性

Resonant characteristics of fiber ring resonator with phase modulation spectroscopy

调相谱检测技术是谐振式光学陀螺信号检测的重要手段。根据贝塞尔函数展开与光场叠加原理,理论分析了光纤环形谐振腔的传输特性;搭建了谐振特性测试系统,采用LiNbO3相位调制,针对不同调制频率与调制电压条件下光纤环的谐振特性和解调曲线特性开展了实验,对实验结果进行分析,得到了调制频率、调制电压与光纤环形谐振腔谐振信号及解调信号之间的关系,实验结果与理论分析相符;并对调制过程中出现的谷裂现象进行了测试与分析,通过实验数据拟合,得到了产生谷裂现象的临界调制频率与调制电压值之间的关系。

Phase modulation spectroscopy is an important method of signal detection in resonator optic gyro. By the use of expansion of Bessel function and optical field overlapping method, the transmission properties of optical fiber ring resonator was analyzed. A testing system of resonant properties was set up. Based on the LiNbO3 phase modulation, the experiments to research resonant characteristics and demodulation curve features was carried out under different frequencies and voltages of modulation, and the experimental result was analyzed, then the relation of frequency and voltage of modulation and resonant and demodulation signal of fiber ring resonator was obtained. The splitting phenomenon of resonance dips during the experiment was measured and analyzed. By fitting the data, the relation of critical frequency and voltage of modulation of splitting phenomenon of resonance dips occurs was obtained.