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

Yuanhong Yang,Wei Jin,Shuai Li,Fuling Yang

doi:10.1109/access.2020.2984006

Abstract

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.

Highlights

After more than forty years of research and development, interferometric fiber optic gyroscopes (FOGs) have achieved remarkably good performance in terms of short-term noise and long-term bias drift
The bias stability of current FOGs is still limited by the effect of transient temperature and further reduction or elimination of errors due to this effect, The associate editor coordinating the review of this manuscript and approving it for publication was Muguang Wang
We report a differential FOG (DFOG) which is composed of two equivalent interferometric FOGs sharing one Sagnac interferometer assembly (SIA) and driven by two broadband sources with different wavelengths

Summary

INTRODUCTION

After more than forty years of research and development, interferometric fiber optic gyroscopes (FOGs) have achieved remarkably good performance in terms of short-term noise (i.e., angle random walk or ARW) and long-term bias drift. Several sources of noise, including coherent backscatters, shot and thermal noises in photoreceiver are largely overcome by using high power broadband sources, leaving the excess source relative intensity noise (RIN) as the dominant noise contributor [5] Techniques such as electronic RIN subtraction [6], optical RIN subtraction [7], using an interferometric filter [8] and application of the Wiener filter [9] have been developed to reduce the RIN and good performance has been achieved. We report a differential FOG (DFOG) which is composed of two equivalent interferometric FOGs sharing one Sagnac interferometer assembly (SIA) and driven by two broadband sources with different wavelengths This DFOG has good common-mode error rejection capability and may achieve low bias drift due to transient temperature by specially designing operational parameters and data processing methods. Yang et al.: Differential FOG Driven by Two Broadband Sources of Different Wavelengths

BASIC PRINCIPLE OF DFOG

THE EFFECT OF TEMPERATURE TRANSIENCE

CONCLUSION