The Compensation of Y Waveguide Temperature Drifts in FOG with the Thermal Resistor

The lithium niobate integrated optical phase modulator (Y waveguide) is the key device in the digital closed-loop fiber optic gyroscope. However, the half-wave voltage of the lithium niobate changes with the environment temperature, which produces the phase bias drift and ultimately decreases the accuracy of FOG. In this manuscript, the thermal resistor is introduced in the amplification part in the driving circuits of Y waveguide. Due to the characteristic of the thermal resistor, the magnitude of driving voltage on Y waveguide changed with temperature to compensate the electro-optic effects temperature drift of the lithium niobate. This method was proved to improve the performance of fiber optic gyroscopes conveniently in experiment.