Centimeter-level spatial resolution over 40 km realized by bandwidth-division phase-noise-compensated OFDR

Area of Science:

• Optoelectronics
• Optical sensing
• Metrology

Background:

• Environmental perturbations degrade spatial resolution in long-range reflectometry.
• Optical source phase noise is a major limiting factor in frequency-domain reflectometry.
• Existing methods struggle to maintain high spatial resolution over extended distances.

Purpose of the Study:

• To introduce a novel bandwidth-division phase-noise-compensated optical frequency domain reflectometry (PNC-OFDR) technique.
• To mitigate the impact of environmental noise and optical source phase noise.
• To achieve high spatial resolution in long-distance fiber optic sensing.

Main Methods:

• Implementing a bandwidth-division strategy for optical frequency sweeping.
• Applying phase noise compensation to the optical source.
• Utilizing the PNC-OFDR technique for reflectometry measurements.

Main Results:

• Achieved sub-centimeter spatial resolution over a 40 km distance in a laboratory setting.
• Demonstrated 5 cm spatial resolution at 39.2 km during a field trial.
• Successfully reduced the influence of environmental perturbations on measurement accuracy.

Conclusions:

• The PNC-OFDR technique significantly enhances spatial resolution for long-range optical sensing.
• This method offers a robust solution for overcoming environmental challenges in reflectometry.
• The findings pave the way for improved distributed fiber optic sensing applications.