A Novel Closed-Loop Control to Solve Light Source Power Fluctuations in the Fiber-Optic Gyroscope

Area of Science:

• Optics and Photonics
• Sensor Technology
• Control Systems Engineering

Background:

• Interferometric fiber-optic gyroscopes (IFOGs) are susceptible to performance degradation caused by light source power (LSP) fluctuations.
• Accurate compensation for LSP fluctuations is crucial for maintaining IFOG performance, especially when the error signal is uncertain.

Purpose of the Study:

• To introduce and evaluate two novel compensation methods, double period modulation (DPM) and triple period modulation (TPM), for uncertain gyroscope errors caused by LSP fluctuations.
• To compare the performance and circuit requirements of DPM and TPM in IFOGs.

Main Methods:

• Implementation of double period modulation (DPM) and triple period modulation (TPM) techniques to mitigate the impact of LSP fluctuations.
• Experimental validation of DPM and TPM performance across a range of LSP fluctuation frequencies (1 kHz to 16 kHz).

Main Results:

• Both DPM and TPM significantly improve bias stability in IFOGs, achieving up to a 95% enhancement at low fluctuation frequencies (1-2 kHz).
• At higher fluctuation frequencies (4-16 kHz), DPM demonstrates superior performance, improving bias stability by approximately 95%, while TPM achieves about 88% improvement.
• DPM offers better performance but requires more complex circuitry, whereas TPM has lower circuit demands, making it suitable for small fiber-coil applications.

Conclusions:

• DPM and TPM are effective strategies for compensating uncertain gyroscope errors arising from LSP fluctuations in IFOGs.
• The choice between DPM and TPM depends on the specific application requirements, balancing performance needs with circuit complexity and size constraints.