RT info:eu-repo/semantics/article
T1 Novel scanning method for distortion-free BOTDA measurements
A1 Domínguez López, Alejandro
A1 Zhisheng, Yang
A1 Soto Hernández, Marcelo Alfonso
A1 Angulo Vinuesa, Xabier
A1 Martín López, Sonia
A1 Thévenaz, Luc
A1 González Herráez, Miguel
K1 Fiber optics sensors
K1 Scattering
K1 Nonlinear optics
K1 Stimulated Brillouin
K1 Fibers
K1 Ciencias tecnológicas
K1 Electrónica
K1 Technology
K1 Electronics
AB Systematic errors induced by distortions in the pump pulse ofconventional Brillouin distributed fiber sensors are thoroughly investigated.Experimental results, supported by a theoretical analysis, demonstrate thatthe two probe sidebands in standard Brillouin optical time-domain analyzersprovide a non-zero net gain on the pump pulse, inducing severe distortionsof the pump when scanning the pump-probe frequency offset, especially athigh probe power levels. Compared to the impact of non-local effectsreported in the state-of-the-art, measurements here indicate that for probepowers in the mW range (below the onset of amplified spontaneousBrillouin scattering), the obtained gain and loss spectra show two strongside-lobes that lead to significant strain/temperature errors. Thisphenomenon is not related to the well-known spectral hole burning resultingfrom pump depletion, but it is strictly related to the temporal and spectraldistortions that the pump pulse experiences when scanning the Brillouingain/loss spectrum. As a solution to this problem, a novel scanning schemefor Brillouin sensing is proposed. The method relies on a fixed frequencyseparation between the two probe sidebands, so that a flat zero net gain isachieved on the pump pulse when scanning the pump-probe frequencyoffset. The proposed technique is experimentally validated, demonstratingits ability to completely cancel out non-local effects up to a probe powerultimately limited by the onset of amplified spontaneous Brillouinscattering. The method allows for one order of magnitude improvement inthe figure-of-merit of optimized long-range Brillouin distributed fibersensors, enabling measurements along a 100 km-long sensing fiber with 2m spatial resolution and with no need of added features for performanceenhancement.
PB Optical Society of America
SN 1094-4087
YR 2016
FD 2016-05-02
LK http://hdl.handle.net/10017/26277
UL http://hdl.handle.net/10017/26277
LA eng
NO European Commission
DS MINDS@UW
RD 29-abr-2024