Distributed vibration sensing with high frequency response by using WDM based integrated scheme
Zhenshi Sun, Kun Liu, Junfeng Jiang, Pengfei Ma, Shuang Wang, Zhongyuan Xu, Hairuo Guo, Zichun Zhou, Tianhua Xu, Tiegen Liu
Abstract
Abstract Distributed vibration sensing measurement with high frequency response is still a challenging task in distributed optical fiber vibration sensing systems. In this paper, a WDM based integrated scheme is proposed to directly demodulate the high frequency vibration signal with high spatial resolution by merging the phase sensitive optical time-domain reflectometry and the Sagnac interferometer. A maximum frequency response of ~2.5 MHz and a spatial resolution of 20 m have been achieved in a 4 km sensing fiber link. Comparison to conventional sensing structure, the proposed scheme shows great application potential in the field of distributed vibration sensing system.