A kind of hybrid optical structure IFOG

This article describes a novel design of the interferometric fiber-optic gyroscope (IFOG) program, that is, a structure of hybrid optical IFOG. It is characterized by using low-polarized light source and single-mode optical fiber coupler in optical head. This optical structure not only can reduce the effect of polarization crosstalk, but also simplifies the assembly process and improves production efficiency. In addition, through the application of all-digital closed-loop control and random modulation signal processing technology, the dead-zone problem in IFOG caused by electronic cross-coupling have been eliminated, and the SNR of gyro output is improved. A large number of experimental testing results have proved that the gyro´s zero-bias instability achieves 0.01°/h, random walk coefficient reaches 0.001°¿(h), and scale factor nonlinearity is less than Sppm (room temperature). The gyro´s performance can meet the requirements of navigation, guidance and control in various fields.