Fiber laser for application in phase sensitive optical time domain reflectometry

Abstract

We have presented fiber laser configuration with an injection locked DFB (IL-DFB) laser for application in phase sensitive optical time domain reflectometry (φ-OTDR). A low-loss fiber optical ring resonator (FORR) is used as a high finesse filter for the self-injection locking of the DFB laser. We have used IL-DFB laser configuration for detection and localization of the vibrations in phase sensitive OTDR system. By applying moving differential processing algorithm for the Rayleigh backscattering traces we demonstrate accurate localization of the vibrations with a frequency ~50 Hz at a distance about 10 km with the same signal to noise ratio that is achievable with an ultra-narrow linewidth OEwaves laser (OE4020-155000-PA-00).