Research Of Narrow Linewidth Brillouin Fiber Laser And Brillouin Fiber Optic Gyro

Since1980THOMAS discovered stimulated Brillouin scattering available in the tachometric survey, the Brillouin fiber gyro obtained widespread attention all over the world, this kind of new fiber gyro does not need several kilometers fiber ring like interference fiber gyro, also eliminates the process of making the complex ring and the temperature control system, has high theory examination precision and good stability, will become an important development direction in the future. The Brillouin fiber gyro essence is the cavity Brillouin optical fiber laser, therefore, how to make high performance, narrow linewidth and low noise Brillouin optical fiber laser, is the most important in the further development of the Brillouin fiber gyro. This paper focuses on the two aspects of the issue in-depth study.First, we conduct the research in the Brillouin optical fiber laser linewidth compression phenomenon, and analyze the influence of linewidth compression phenomenon to the Brillouin fiber optic gyro in this foundation. First we derive stimulated Brillouin scattering model in single-mode fiber resonant cavity, then established laser linewidth compression model in Brillouin mirror condition, then we obtain optical phase relation through model approximate calculation, finally we carry on the confirmation through the experiment of the linewidth compression phenomenon. A simple optical field overlap method is reported to calculate circulating light intensity in Brillouin fiber ring resonator based on laser coherence theory. The influence of resonance characteristics by spectral linewidth is analyzed. Furthermore, analysis has been made of the relationship between spectral linewidth, threshold of simulated Brillouin scattering and resonator sensitivity. Analysis showed that in the condition of same parameters of resonator, the sensitivity of B-FOG is about three orders higher than R-FOG.Second, relative intensity noise in Brillouin fiber laser is studied in detail. The relative intensity noise transfer function about injection rate fluctuations and pump fluctuations is derived based on the analysis of the relative intensity noise in Brillouin fiber laser sources and laser Classic stimulated Brillouin scattering wave equation. Then laser frequency stabilization is studied. PDH technology in Fabry-Perot interferometer is improved and used in Brillouin fiber laser. Finally the relative intensity noise is successfully measured.Finally, because the Kerr effect is the largest error source in Brillouin fiber optic gyro, the Kerr effect and its derivative phenomena has been studied in detail. Kerr effect in Brillouin fiber gyro is briefly described. Brillouin fiber gyro Kerr effect errors model is established based on photonic bandgap fiber for a new Kerr effect elimination scheme. Through numerical calculation and comparison with single-mode fiber scheme, feasibility of the scheme under different pressure and different fill substances is analyzed; for small dynamic range of Brillouin fiber gyro, a new dynamic range increasing scheme is designed.