Nonlocal Effect Compensation in Frequency-Fixed Probe Based BOTDA Sensor

• DOI: 10.1109/jlt.2017.2761379
• Publication Date: 2017-10-09T18:10:31Z
• Authors: Sheng Wang; Zhisheng Yang; Xiaobin Hong; Wenqiao Lin; Jian Wu
• Keywords: Brillouin zone; Robustness; Distributed Acoustic Sensing

The robustness of a recently proposed Brillouin optical time-domain analysis sensor based on dual-tone probe wave with fixed frequency separation is deeply studied. It discovered that when the distribution shift (BFS) along sensing fiber not entirely uniform, non-local effect might be imposed at middle fiber, which gives rise to systematic error local estimated BFS. Aiming solving this problem, we propose an approach acquires both upper and lower sidebands simultaneously using two photodiodes, average between gain loss spectral calculated eliminate detrimental impact effect. Moreover, power distortions pump pulse gain/loss spectrum experimentally investigated, thus maximum allowable injection determined.