Open AccessPhase demodulation of interferometric fiber sensor based on fast Fourier analysis
Author(s) -
Xin Fu,
Ping Lü,
Wenjun Ni,
Hao Liao,
Deming Liu,
Jiangshan Zhang
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.021094
Subject(s) - demodulation , optics , interferometry , multi mode optical fiber , cladding (metalworking) , fourier transform , materials science , fiber optic sensor , wavelength , optical fiber , physics , computer science , telecommunications , channel (broadcasting) , quantum mechanics , metallurgy
A demodulation method for interferometric fiber sensors (IFSs) is proposed in this article. The phase variation induced by the measurands can be estimated by calculating the Fourier phase at the intrinsic spatial frequencies of the fiber sensor. Theoretical analysis of the demodulation method is discussed in detail. Numerical simulations are put forward to demonstrate the consistency of the demodulation results under different wavelength sampling interval and noise level, showing a better stability compared with the conventional peak wavelength tracking technique. The proposed method is also experimentally demonstrated by an inline multimode interferometer based on a single-mode fiber (SMF) offset-splicing structure. Experimental results indicate that the phase response of different cladding modes can be analyzed simultaneously. Simultaneous measurement of strain and temperature is realized in our confirmatory experiment by analyzing the phase sensitivities of two selected cladding modes.