Compensation for the asymmetry error of resonant optical gyroscope via second harmonic demodulation curves

Asymmetry error from the optical devices fabrication error is one of the main factors influencing the performance of resonant optical gyroscope (ROG). Research on the compensation of asymmetry error is meaningful to improve the performance of ROG. We theoretically analyze the difference of first harmonic demodulation curves in two loops and propose an effective method to compensate the asymmetry error via second harmonic demodulation curves. The experimental results show that, with our method, the bias stability of the gyroscope output is greatly reduced from 186°/h to 9°/h. •Theoretically analyze the asymmetry error of resonant optical gyroscope.•An effective method to compensate the asymmetry error via second harmonic demodulation curves is proposed.•The bias stability of the gyroscope output is greatly reduced from 186°/h to 9°/h.