Performance improvement of white-light-driven resonant fiber optic gyroscope using four-frequency sawtooth wave modulation technology

In this study, a novel resonant fiber optic gyroscope (RFOG) that relies on four-frequency sawtooth wave modulation technology is proposed. This innovative approach is utilized to demodulate both the light intensity changes of the optical system and the half-wave voltage drift of the multi-functional integrated optical chip (MIOC). The principle of modulation is expounded, and a simulation model is established to evaluate the performance of the system. We conducted synchronous compensation of the bias drift, which is caused by the light intensity changes, and applied closed-loop control to MIOC modulation frequency-shift voltage, effectively reducing the scale factor error. As a result, the system achieved a bias instability (BI) of 0.0055°/h, with a 500 m-long fiber-optic ring resonator (FRR) of 6 cm diameter, at room temperature. Furthermore, the scale factor error was reduced by more than threefold in the temperature range of −40 °C to 70 °C. These results demonstrate the superior performance of the proposed RFOG and its potential for high-precision navigation and other applications.