Dynamic and High-Resolution Strain Measurements Using the Brillouin Optical Frequency-Domain Analysis

In this work, we demonstrate a novel mechanism to localize the stimulated Brillouin interaction over a specific portion of an optical fiber, using a Brillouin Optical Frequency-Domain Analysis (BOFDA) interrogation system and an array of tapers. We show, both numerically and experimentally, that the frequency-domain fiber response, acquired over a narrow range by a vector network analyzer, can be uniquely associated to the multi-taper array whose period matches the swept spectral range. This opens the way to high-resolution (cm-scale) dynamic strain measurements, in addition to fully distributed static strain (or temperature) measurements over the same optical fiber and using the same apparatus.