Differential Fiber Optic Gyroscope Driven by Two Broadband Sources of Different Wavelengths

We propose a differential fiber optic gyroscope driven by two broadband light sources with different wavelengths. Preliminary experiments demonstrate that both bias drift and angle random walk can be reduced considerably due to common-mode error cancellation. Theoretical analysis shows that the effect of transient temperature could be eliminated by optimizing the dispersion of the fiber coil and/or by introducing a dispersion compensation factor before taking the differential operation. Experiments with a fiber coil with weak wavelength-dependent dispersion coefficient show that significant reduction of bias drift due to transient temperature can be achieved with a proper dispersion compensation factor.