Sensitivity analysis of the Sagnac-effect optical-fiber ring interferometer.

Area of Science:

• Photonics
• Optical Engineering
• Inertial Navigation

Background:

• Optical-fiber ring interferometers are explored for gyroscope applications.
• Photomixing signal-to-noise ratios (SNRs) are crucial for detection schemes.

Purpose of the Study:

• Analyze the sensitivity of optical-fiber ring interferometers as gyroscopes.
• Quantitatively assess noise sources impacting gyroscope performance.
• Determine optimal gyroscope sensitivities under various conditions.

Main Methods:

• Derived photomixing SNRs for different detection schemes.
• Quantitatively assessed noise from Rayleigh, Brillouin, Mie, and core-cladding scattering.
• Performed numerical analysis using optical wavelengths of 0.633 and 1.1 micrometers.
• Evaluated both spontaneous and stimulated noise effects.

Main Results:

• Mode stripping is essential to reduce trapped scattered light by 100x.
• The 1.1 micrometer wavelength offers more promising results.
• High optical power operation, dominated by stimulated Brillouin scattering, yields superior sensitivity compared to low-power operation.
• Achieved sensitivities of 0.0009 deg/h at 81 mW (0.633 µm) and 0.0007 deg/h at 14.4 mW (1.1 µm).

Conclusions:

• Optimized optical-fiber ring interferometers demonstrate enhanced gyroscope sensitivity.
• The findings suggest potential for improved inertial navigation systems.
• Calculated sensitivities surpass those of current laser ring gyroscopes.