Influences of pulse parameters on the performance of double-pulse ϕ-OTDR

In the past decade, an increasing number of studies of double-pulse ϕ-OTDR systems have been reported, but so far, there are no studies specifically analyzing the influences of double pulses on system performance. In this paper, we construct a theoretical model of the double-pulse ϕ-OTDR system, ana...

Full description

Saved in:
Bibliographic Details
Published in:Optics and laser technology 2023-06, Vol.161, p.109128, Article 109128
Main Authors: Zhong, Xiang, Chen, Xiaoshan, Cao, Hanyu, Deng, Huaxia, Ren, Jie, Xiao, Xingzhi, Sun, Yu, Ma, Mengchao
Format: Article
Language:English
Subjects:
Demodulation range
Double probe pulses
Phase-sensitive optical time domain refractometry
Spatial resolution
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In the past decade, an increasing number of studies of double-pulse ϕ-OTDR systems have been reported, but so far, there are no studies specifically analyzing the influences of double pulses on system performance. In this paper, we construct a theoretical model of the double-pulse ϕ-OTDR system, analyze the interference process of the system theoretically, and make conjectures on spatial resolution and demodulation range. On the basis, we build a double-pulse ϕ-OTDR experimental setup based on Sagnac balanced interferometer. The feasibility of the proposed theory is verified by experiments altering the probe pulse parameters and localizing two-point disturbances at different frequencies. The results also indicate when pulse width is greater than the pulse interval, this system offers more accurate positioning capabilities and a continuous demodulation range with high fidelity. The conclusions provide a reference for the selection of appropriate double-pulse parameters for similar systems, and the theoretical model offers a methodological suggestion for exploring other types of double pulses or even multi-pulse systems. •The influences of pulse width τ and interval w on double-pulse ϕ-OTDR are studied.•When τ< w, the recoverable perturbed signal area is divided into two parts of 2:1.•When τ< w, one-point perturbation is detected as two points causing nuisance alarm.•When τ≥ w, the localization is more accurate and demodulation range is continuous.•The study provides a reference for selecting parameters for double-pulse ϕ-OTDR.
ISSN:0030-3992
1879-2545
DOI:10.1016/j.optlastec.2023.109128