We have evaluated the performance of a phase-sensitive optical time domain reflectometry (φ-OTDR) system for vibration measurements utilizing a conventional telecom DFB laser self-stabilized through an external PM optical fiber ring resonator. This low-cost solution is directly compared with the use of a commercial, ultra-narrow linewidth (∼100 Hz) fiber laser implemented into the same setup. Both systems are tested for measurement of the frequency of vibration applied to a fiber at a distance of 3500 m. The obtained SNR value higher than 6 dB demonstrates the ability of the DFB laser to perform distributed measurements of vibrations with frequencies up to 5600 Hz with a spatial resolution of 10 m.
Bibliographical note© 2019 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license
- Frequency examination
- Phase-sensitive OTDR
- Self-injection locking