Error analysis of dual-polarization fiber optic gyroscope under the magnetic field-variable temperature field

摘要

A dual-polarization fiber optic gyroscope system is built to systematically analyze the nonreciprocal errors of the system under the magnetic field-variable temperature field. Under the magnetic field-variable temperature field, the nonreciprocal errors are caused by magnetic-thermal coupling birefringence nonreciprocal error, linear birefringence nonreciprocal error and Shupe effect error. The nonreciprocal errors of dual-polarization fiber optic gyroscope system are related to temperature and temperature gradient. In X and Y polarization states, the signs of magnetic-thermal coupling birefringence nonreciprocal error and linear birefringence nonreciprocal error are opposite, and these two errors can be suppressed in the dual-polarization system. But the Shupe effect errors are the same in X and Y polarization states, which can not be suppressed in the dual-polarization system. The experimental results are consistent with the theoretical analysis, which verifies the correctness of the nonreciprocal error model under the magnetic field-variable temperature field. The research results provide a theoretical and experimental basis for the study of the environmental adaptability of the fiber optic gyroscope and other common-path fiber sensing systems based on dual-polarization.