Fiber-optic gyroscope for the suppression of a Faraday-effect-induced bias error

Abstract

Inertial rotation sensors, interferometric fiber-optic gyro scopes (IFOGs), are widely used in military and industrial applications due to their high sensitivity and stability. In this Letter, a new, to the best of our knowledge, fiber coil design is proposed to reduce magnetic field sensitivity without adding any optical components or electronic algo rithms to the IFOG system. It is shown that this design can be applied without disturbing the simplest IFOG struc ture. Considering the fact that the magnetic field has an invertible effect on polarization, the compensation of the Faraday-effect-induced bias error has been demonstrated theoretically and experimentally by allowing two different polarizations to travel inside the fiber coil. According to the experimental results, the bias error was reduced approxi mately 20 times from ± 9.6◦ /h/mT to ± 0.5◦ /h/mT.