Distributed Sensing Based on Interferometry and Polarization Methods for Use in Fibre Infrastructure Protection.

Area of Science:

• Telecommunications Engineering
• Optical Sensing Technologies

Background:

• Fiber optic infrastructures are critical for modern communication networks.
• Fiber optic cable cuts, often caused by excavation, lead to significant network outages.
• Proactive detection of potential fiber cuts is essential for network operators.

Purpose of the Study:

• To evaluate direct detection-based distributed fiber optic sensing systems for predicting fiber cuts.
• To compare the sensitivity and accuracy of interferometric and polarization sensing systems for acoustic vibrations.
• To determine the suitability of these systems for detecting digging activity before fiber breakage.

Main Methods:

• Laboratory measurements were conducted to assess sensing system performance.
• Interferometric and polarization-based distributed fiber optic sensing systems were analyzed.
• Both systems were subjected to acoustic vibrations to simulate external disturbances.

Main Results:

• Direct detection systems offer a viable solution for detecting events before fiber breakage.
• The study compared the sensitivity and accuracy of interferometric and polarization sensing techniques.
• Interferometric systems utilized reference and sensing arms within the same cable, both exposed to acoustic vibrations.

Conclusions:

• Distributed fiber optic sensing is a promising technology for preventing fiber optic cable damage.
• Understanding the performance of different sensing modalities (interferometric vs. polarization) is key to selecting the appropriate system.
• Early detection of acoustic disturbances can mitigate network outages caused by digging.