Matching pairs based on the differential pigtail interferometric fiber optic gyroscope polarization error suppression method of the nonreciprocal

The present invention discloses a method based on matching pairs pigtails differential interferometric fiber optic gyro nonreciprocal polarization error suppression method. This method first fused fiber coupler and the point as the node, differential interference double pigtail fiber optic gyro with the optical fiber in the beam path segment identifier, and to obtain a wide-spectrum light source coherence length; followed by obtaining two gyro primary wave train, a phase and amplitude and polarization cross-coupling of the secondary wave trains; and having the same polarization state at the output of the gyro wave phase columns pairwise subtracted, obtaining a phase difference; and finally converting the phase difference of optical path difference, configuration inequalities, so that the coherence between the main wave satisfies the condition, coupling between the main wave and the wave train, the coupling between the coupled wave train of coherent wave train to meet the conditions, and the length of each length of fiber pigtails inequalities adjusted. The present invention is achieved effectively suppressed double differential interferometric fiber optic gyro nonreciprocal polarization error, improve the detection accuracy of the differential double interferometric fiber optic gyroscope.