Optical Engineering • Open AccessNew measurement method for eigen frequency of a fiber optic gyroscope
Eigen frequency is a very important parameter in a fiber optic gyroscope (FOG). To establish an accurate measurement of eigen frequency, we propose a new measurement method based on employing the square-wave, over-bias modulation with double eigen frequency. We investigate the proposed method both experimentally and theoretically. Experimental results show the measurement accuracy of eigen frequency is better than ±5 Hz, which satisfies the eigen frequency measurement of most FOGs. A theoretical model of the method gives a good explanation of the experimental results. The method is simple, low-cost, and easy to implement. In addition, it can greatly improve the accuracy of the eigen frequency measurement without needing additional hardware for existing gyro systems.