Magnetic-thermal coupling effect of depolarized interferometric fiber optic gyroscope under low temperature field

The magnetic-thermal coupling effect, which can result in a serious non-reciprocal error, can’t be ignored in high-performance depolarized interferometric fiber optic gyroscope (De-IFOG). In this paper, we research on the magnetic-thermal coupling effect under varying temperature field in De-IFOG theoretically and experimentally. The mechanism of the coupling effect is thoroughly investigated and the related theoretical calculation model is established. The essential differences between the errors caused by varying temperature field and magnetic-varying temperature field are analyzed respectively. Simulations and experiments are consistent with the theoretical model. The experimental results show that, when the temperature varies from -30℃ to 20℃ at the speed of 14℃/h, the peak to peak value of error is up to 35 °/h with a constant magnetic field of 10 Gauss. The results can be used to enhance environmental adaptability of devices such as De-IFOGs, which are in great demands for aerospace applications.