Analysis of temperature errors in digital closed-loop fiber optic gyroscope

The cause of the temperature errors in digital close-loop fiber optic gyroscopes (FOG) was analyzed. The temperature errors mainly included temperature noise, scale factor drift, and bias shift. A method for separating the temperature noise from temperature drift of the FOG, which was based on discrete wavelet transformation, was presented. The method was used to analyze the test data. It is evidenced that temperature drift is the main temperature error when the zero bias instability of FOG was higher than 0.3 (°)/h. Through combination of the simplified effective phase model with the temperature -sensitivity parameter model of FOG, its distribution model of temperature drift error was obtained. From this model, the factors that influence the temperature drift error were analyzed. And the main factors were tested and discussed. In the end, several measures to suppress the temperature drift error were summarized.