All Digital Closed-loop Fiber Optic Gyroscope with the Second Feedback Loop

Aiming at all digital closed-loop fiber optic gyroscope,the influence of scale factor and bias stability was analyzed when ramp voltage reset was no ideal. The gain of the phase modulation chain would be self-correcting by means of employing the second feedback loop. The method of reset error demodulation was studied. Based on the law of integral control, the transfer function of the second feedback loop was established. Transition process and steady error were discussed. The experimentation results showed that the second feedback loop could eliminate reset error and improve performance of gyroscope without disturbance of master loop.