title: Coherent Φ-OTDR based on I/Q demodulation and homodyne detection.
abstract: We demonstrate a novel distributed acoustic sensing (DAS) system based on phase-sensitive optical time-domain reflectometry (Φ-OTDR). Both the phase and the amplitude of the Rayleigh scattering (RS) light can be demodulated in real-time. The technique is based on I/Q demodulation and homodyne detection using a 90° optical hybrid. The theoretical analysis is given, and as a proof of the concept, the dynamic strain sensing is experimentally demonstrated, with a sensing range of 12.566 km and a spatial resolution of 10 m.
authors.forename: Zinan
authors.initials: Z
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Song
authors.initials: S
authors.lastname: Wang
authors.forename: Naitian
authors.initials: N
authors.lastname: Xue
authors.forename: Fei
authors.initials: F
authors.lastname: Peng
authors.forename: Mengqiu
authors.initials: M
authors.lastname: Fan
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Xianyang
authors.initials: X
authors.lastname: Qian
authors.forename: Jiarui
authors.initials: J
authors.lastname: Rao
authors.forename: Yunjiang
authors.initials: Y
authors.lastname: Rao