title: Optimization of a DPP-BOTDA sensor with 25 cm spatial resolution over 60 km standard single-mode fiber using Simplex codes and optical pre-amplification.
abstract: Sub-meter distributed optical fiber sensing based on Brillouin optical time-domain analysis with differential pulse-width pairs (DPP-BOTDA) is combined with the use of optical pre-amplification and pulse coding. In order to provide significant measurement SNR enhancement and to avoid distortions in the Brillouin gain spectrum due to acoustic-wave pre-excitation, the pulse width and duty cycle of Simplex coding based on return-to-zero pulses are optimized through simulations. In addition, the use of linear optical pre-amplification increases the receiver sensitivity and the overall dynamic range of DPP-BOTDA measurements. Experimental results demonstrate for first time a spatial resolution of ~25 cm over a 60 km standard single-mode fiber (equivalent to ~240 k discrete sensing points) with temperature resolution of 1.2°C and strain resolution of 24 με.
authors.affiliation: Scuola Superiore Sant’Anna, TeCIP Institute, via G. Moruzzi 1, 56124 Pisa, Italy.
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Soto
authors.forename: Mohammad
authors.initials: M
authors.lastname: Taki
authors.forename: Gabriele
authors.initials: G
authors.lastname: Bolognini
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Di Pasquale
mesh_terms: D000669:Amplifiers, Electronic; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D055100:Optical Fibers; D012031:Refractometry / Q000295:instrumentation*; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D014159:Transducers