Theoretical Study And Structural Design Of High Q - Cavity Gyroscope

Resonant optical gyroscope is the angular velocity sensor testing system based on Sagnac effect, compared with mechanical gyroscopes, resonant gyroscope has many advantages like no moving parts, low energy consumption, long service life, impact resistance, easy maintenance and so on, compared with interferometric gyroscopes, resonant gyroscope can use much shorter optical fiber to obtain the same limit sensitivity in theory. So it is helpful to realize miniaturization, low cost, and reduce the Shupe effect. It is a new type of gyro which has great competitive. While as the core unit, resonant cavity’s performance parameters directly affect the sensitivity and finesses of gyro.This article firstly explains the theoretical analysis of resonant optical gyroscope, then discusses the working principle and the basic performance parameters of resonant cavity, mainly studied the static and dynamic characters which measure the performance of gyroscope. Above all, we showed the variation trend of sensitivity and Q value of gyroscope when it comes to/considering the laser line width, cavity size, coupling coefficient of the coupler and the transmission loss.To achieve the requirement of high Q resonant cavity structure, this paper combines the research for various high performance cavity, both at home and abroad, on the basis of theoretical research, design the coupler with different structure and analyzes the effects on gyro of different coupling coefficient and fiber loss.According to the physical model and operational principle of various resonant cavity with different materials and different structure, we analyzed structure parameters of various cavity and it’s gyroscopic effect in theory and in experiment, such as the light output characteristics, sensitivity and finesses of gyroscope. After statistical analysis and comparison of them, we present an optimized resonant cavity structure with high Q value, so as to obtain the main way to obtain high resolution of the gyro.All kinds of noise which exist in experiment system had been analyzed, and their generating mechanisms were all listed in detail. According to the different noise, different modals were established to suppress it. Gyroscope testing system platform was build, and the frequency tracking and locking and step effect were discussed.Realized the test of zero bias stability, resonance spectral line, modulation curve and demodulation curve, finally obtained a high sensitivity gyro rotation experiment system with high Q micro cavity.