Quasi-distributed fiber sensitization sensing technique based on FMCW interferometry and the virtual Vernier effect
Year: 2025
Type: article
Abstract: A quasi-distributed fiber-optic sensitized sensing technique based on Fabry Perot (FP) microcavities is proposed by integrating frequency-modulated continuous-wave (FMCW) interferometry with the Vernier effect. An open-cavity structured FP sensor (FP-Sen) was fabricated for seawater salinity detection. Precise localization and interferometric spectral demodulation of multiple FP-Sens were achieved by compensating for the nonlinear tuning errors of the laser source using a digital signal processing (DSP) algorithm. The virtual interferometric spectrum (VIS) of multiple virtual sensors (V-Sens) was constructed according to the interferometric formula and superimposed with the interferometric spectrum of the FP-Sen to generate the optical Vernier effect. Sensitized salinity measurements were then realized by monitoring the drift of the Vernier envelope spectrum. Experimentally, a quasi-distributed FMCW system with three cascaded FP-Sens was employed to obtain high spatial resolution fiber-optic link information and to verify the feasibility of multipoint salinity sensitization. The sensitivity of the FP-Sen reached 2.235 nm/‰ within the salinity range of 25-30‰, achieving a 9-times sensitivity enhancement compared to a single sensor. Additionally, stability analysis using violin plots demonstrated that the fabricated FP-Sens exhibited good stability. The proposed technique offers clear advantages in practical applications requiring a large number of sensitized sensing points.
Source: Optics Express
DOI: 10.1364/oe.577399
Authors: Chengyu Mo, Yuqiang Yang, Jin Yan, Han Xia, Zhihao Huang, Yuting Li
Institution: Guangdong Ocean University
Language: English
Topic: Advanced Fiber Optic Sensors
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
Awards: G4056172501, G5470935247, G7558020396
OpenAlex ID: W4415606170
