Real-time control of the work point in all digital open-loop FOG

The work point in a practical open loop Fiber Optic Gyroscope (FOG) must be controlled. A work point control method in all digital open-loop FOG is presented. According to the work point, gotten through the second and fourth harmonic components in open loop FOG signal, the control system adjust the amplitude of the modulation signal to control the work point without adding any hardware. The experimental results show the control method can stabilize the work point of open loop FOG in large temperature range. The control stability is 1.16×10-3 , bias is 3.1×10-4 and the start-up time is less than 10s from – 40℃ to 60℃