RT info:eu-repo/semantics/article T1 Fully distributed optical fiber strain sensor with 10−12ε/√Hz sensitivity A1 Pereira da Costa, Luis Duarte A1 Fidalgo Martins, Hugo A1 Martín López, Sonia A1 Fernández Ruiz, María del Rosario A1 González Herráez, Miguel K1 Chirp modulation K1 Optical fiber applications K1 Optical time domain reflectometry K1 Phase noise K1 Remote sensing K1 Strain measurements K1 Vibration measurements K1 Electrónica K1 Electronics AB Advanced optical fiber reflectometry techniques enable spatially distributed measurements of true relative deformations over the length of a conventional optical fiber cable. This methodology is attractive for many applications ranging from intrusion monitoring to seismology. However, accurate quantification of the applied stimulus in general implies sophisticated implementations with poor sensitivity performance. Coherent reflectometry using chirped pulses is an appealing solution, as it provides fast dynamic strain measurements with a simple experimental deployment. Here, we analyze for the first time to our knowledge the lower performance bounds of this technique as a function of the signal-to-noise ratio of the acquired optical signal. We demonstrate that implementations realized so far have been limited by the temporal sampling used instead of the optical signal quality. Through post-processing interpolation approaches, we reach the performance limit for a given set of signal parameters, attaining unprecedented strain sensitivities (∼10−12epsilon/√Hz) for km-length distributed sensors in conventional single-mode fibers. SN 0733-8724 YR 2019 FD 2019-09-15 LK http://hdl.handle.net/10017/39528 UL http://hdl.handle.net/10017/39528 LA eng NO European Commission DS MINDS@UW RD 29-mar-2024