The Demodulation Characteristic And Noise Influence Of Resonator Integrated Optical Gyro

Gyroscope is a kind of inertial sensor that is used to measure object rotation angular velocity, and widely used in the fields of aerospace, navigation and so on. With the development of integrated optics technology, Resonator Integrated Optic Gyroscope(R-IOG) shows good development prospects.At present,the modulation schemes of resonator integrated optic gyro based on Si-based optical waveguide are more than others,and their most used the LiNbO3 phase modulation technology.Due to the phase detection method introduces LiNbO3 phase modulator which different from Si-based optical waveguide and it’s not conducive to integration of gyroscopic.Laser frequency modulated detective method is an ideal detective technology.This thesis adopts the laser frequency modulated detective technology based on Si-based optical waveguid.This thesis included three parts as follows:(1)According to the resonance characteristics of resonator,we derived the transfer function of resonator in the frequency domain.Which will help to the modeling and simulation of demodulation characteristic in the laser frequency modulation technology.(2)In the laser frequency modulation spectroscopy technique of resonator integrated optic gyroscope, the relationship between the demodulated output signal and resonant frequency deviation has been analyzed by utilizing the methods of Bessel function expansion and the optical field superposition. According to the analytical expressions of the demodulated output signal, we analyzed the variation of the demodulation curve through numerical calculation. The conclusion is that the demodulation characteristics are the most ideal when modulation coefficient of M=10000(3)We analyzed the impact and suppression method of the main noise on R-IOG. The major analyses are focus on the backscattering noise, polarization fluctuation noise and the effect of optical Kerr effect on gyroscope.(4)We built the demodulation curve detection system of waveguide ring resonator by using laser spectral frequency modulation technology. The Resonance depth and fineness of waveguide ring resonator is raised from 0.7831 to 0.9537 and from 30.15 to 36.72 after polarization fluctuation noise is suppressed, respectively. The demodulation curve is detected and the dynamic range of calculated gyroscope is ±2.04×103 rad/s.