Application of superresolution techniques to ring laser gyroscopes: exploring the quantum limit

Area of Science:

• Physics
• Optical Engineering
• Signal Processing

Background:

• Accurate linewidth estimation is crucial for characterizing signal quality in various scientific instruments.
• Partially coherent signals with white frequency fluctuations present challenges for traditional linewidth estimation methods.
• Ring laser gyroscopes are sensitive to noise, necessitating precise linewidth analysis for optimal performance.

Purpose of the Study:

• To introduce and compare two distinct methods for extracting linewidth estimates from noisy, partially coherent signals.
• To evaluate the reliability and applicability of these methods, particularly for short data segments.
• To demonstrate the practical application of these techniques in the context of quantum-noise-limited ring laser gyroscopes.

Main Methods:

• Method 1: Allan deviation, which requires multiple frequency estimates per linewidth estimate.
• Method 2: Second-order autoregressive (AR(2)) model, providing a linewidth estimate with each frequency estimate.
• Characterization and comparative analysis of both methods using simulated and experimental data.

Main Results:

• The second-order autoregressive model demonstrates reliability for short data sets (less than or equal to 1 second).
• Application to large, quantum-noise-limited ring laser gyroscopes shows favorable comparison with theoretical predictions.
• The AR(2) method offers a more efficient linewidth estimation approach for specific noise conditions.

Conclusions:

• The second-order autoregressive model is a robust and efficient technique for linewidth estimation in challenging signal conditions.
• This method is particularly advantageous for analyzing short data records common in high-sensitivity instruments like ring laser gyroscopes.
• The findings validate the practical utility of advanced signal processing techniques for improving optical sensor performance.