Suppressing polarization non-reciprocity error with reverse phase modulation in dual-polarization fiber optic gyroscopes.

In a dual-polarization interferometric fiber optic gyroscope (IFOG), polarization non-reciprocity (PN) errors are significant, which degrades the IFOG performance due to the polarization coupling between two orthogonal axes. A dual-polarization IFOG with reverse phase modulation is proposed in which PN phase error can be sufficiently suppressed. In our scheme using a 2-km polarization maintaining coil with open-loop configuration, angle random walk of 4.

Effective suppression of residual coherent phase error in a dual-polarization fiber optic gyroscope.

The impact of residual coherent phase error in a dual-polarization interferometric fiber optic gyroscope (IFOG) is investigated. Although it has been intuitively assumed that the coherence of a light source can be eliminated by a sufficient long fiber delay, the experiment and theory indicate that it still contributes a remarkable portion to long-term instability. After the residual coherent phase error is well handled, we demonstrate a dual-polarization IFOG with bias instability of 3.

Compensation of thermal strain induced polarization nonreciprocity in dual-polarization fiber optic gyroscope.

Dual-polarization interferometric fiber optic gyroscope (IFOG) is a novel scheme in which the polarization nonreciprocal (PN) phase error of the two orthogonal polarizations can be optically compensated. In this work, we investigate the effective of PN phase error compensation under varying temperature. It is proved that, the thermally induced strain deforms the fiber, and results in perturbations on the birefringence and polarization cross coupling which degrades the IFOG's stability.

Polarization nonreciprocity suppression of dual-polarization fiber-optic gyroscope under temperature variation.

Polarization nonreciprocity (PN) is one of the most critical factors that degrades the performance of interferometric fiber-optic gyroscopes (IFOGs), particularly under varying temperature. We present an experimental investigation of PN error suppression in a dual-polarization IFOG. Both experimental results and theoretical analysis indicate that the PN errors of the two orthogonally polarized light waves always have opposite signs that can be effectively compensated despite the temperature variation.

Dual-polarization interferometric fiber-optic gyroscope with an ultra-simple configuration.

We demonstrate a novel dual-polarization interferometric fiber-optic gyroscope (IFOG), which needs only one coupler and no polarizer. Polarization nonreciprocity (PN) errors in common IFOGs will increase significantly if the polarizer is absent, or if only one coupler is used. In our setup, however, PN errors are effectively compensated by using two balanced polarizations.