SNR enhancement in high-resolution phase-sensitive OTDR systems using chirped pulse amplification concepts

Abstract

Phase-sensitive optical time-domain reflectometry ($\phi \mathrm{OTDR}$) is widely used for the distributed detection of mechanical or environmental variations with resolutions of typically a few meters. The spatial resolution of these distributed sensors is related to the temporal width of the input probe pulses. However, the input pulse width cannot be arbitrarily reduced (to improve the resolution), since a minimum pulse energy is required to achieve a good level of signal-to-noise ratio (SNR), and the pulse peak power is limited by the advent of nonlinear effects. In this Letter, inspired by chirped pulse amplification concepts, we present a novel technique that allows us to increase the SNR by several orders of magnitude in $\phi \mathrm{OTDR}$-based sensors while reaching spatial resolutions in the centimeter range. In particular, we report an SNR increase of 20 dB over the traditional architecture, which is able to detect strain events with a spatial resolution of 1.8 cm.

© 2017 Optical Society of America

Single-shot distributed temperature and strain tracking using direct detection phase-sensitive OTDR with chirped pulses

J. Pastor-Graells, H. F. Martins, A. Garcia-Ruiz, S. Martin-Lopez, and M. Gonzalez-Herraez
Opt. Express 24(12) 13121-13133 (2016)

High spatial resolution phase-sensitive optical time domain reflectometer with a frequency-swept pulse

Bin Lu, Zhengqing Pan, Zhaoyong Wang, Hanrong Zheng, Qing Ye, Ronghui Qu, and Haiwen Cai
Opt. Lett. 42(3) 391-394 (2017)

Ultra-long high-sensitivity Φ-OTDR for high spatial resolution intrusion detection of pipelines

Fei Peng, Han Wu, Xin-Hong Jia, Yun-Jiang Rao, Zi-Nan Wang, and Zheng-Pu Peng
Opt. Express 22(11) 13804-13810 (2014)

Phase-sensitive OTDR probe pulse shapes robust against modulation-instability fading

Maria R. Fernández-Ruiz, Hugo F. Martins, Juan Pastor-Graells, Sonia Martin-Lopez, and Miguel Gonzalez-Herraez
Opt. Lett. 41(24) 5756-5759 (2016)

High spatial resolution distributed fiber system for multi-parameter sensing based on modulated pulses

Jingdong Zhang, Tao Zhu, Huan Zhou, Shihong Huang, Min Liu, and Wei Huang
Opt. Express 24(24) 27482-27493 (2016)