Dsp-based Resonator Fiber Optic Gyro Closed-loop Detection System

Resonator fiber optic gyroscope(RFOG) has become the key research point now because of its high precision and miniaturization. Digital closed detection method has been widely used in fiber optic gyro, because it can gain large dynamic range and improve fiber scale factor.This thesis from the angle of signal detection, first theoretically gives out a RFOG closed signal detection design based on DSP. The signal detection system mainly includes related detection. signal conversion and the formation of feedback saw tooth. Related detection must guarantee signal synchronization sampling, and get the biggest signal noise ratio.Then this thesis discusses the concrete algorithm in the signal detection scenario. In a R-FOG, because of the rotation of the resonator, the resonatorfrequency varies. And this causes a frequency change Δf. The resonant point tracing algorithm describes how to detect Δf. So it can introduce a feedback frequencydifference -Δf through a closed loop to realize the resonant state o In the digitaldetection scenario, using staircase wave to replace saw tooth wave, it can overcome a lot of shortcomings in the analog system. The character of the staircase wave affects the detection precision directly. This thesis analyzes a high precision scenario producing a staircase waveform in detail. It can reduce the number of the bits in D/A converter greatly. This thesis proposes another method to improve the detection precision in case that the A/D converter has comparatively little number of bits, while this method will not increase the cost of the system greatly.In the end, the thesis finishes the realization of the detection system both in hardware and software according to the proposed signal detection scenario. With emulation it proves that this scenario can meet the demand of the system precision and response time.