M.A. Taranov – Engineer, 

Fryazino Branch of Kotelnikov Institute of Radioengineering and Electronics of RAS

E-mail: tarma@petrofibre.ru

B.G. Gorshkov – Dr.Sc. (Eng.), Leading Research Scientist, 

Prokhorov General Physics Institute of RAS (Moscow)

A.E. Alekseev – Ph.D. (Phys.-Math.), Senior Research Scientist, 

Fryazino Branch of Kotelnikov Institute of Radioengineering and Electronics of RAS

V.T. Potapov – Dr. Sc. (Eng.), Head of Laboratory, 

Fryazino Branch of Kotelnikov Institute of Radioengineering and Electronics of RAS

Problem formulating. Fiber-optic distributed strain and temperature sensors based on registration of Rayleigh scattering spectra are a promising solution for structural health monitoring (SHM) of infrastructure facilities. Previously proposed devices of this kind with a high-coherence optical radiation source have a very narrow measuring range and thus do not meet SHM requirements, which prompts us to explore the possibilities of an alternative solution – a reflectometer with a low-coherence radiation source.

Goal. To consider the principle of distributed strain and temperature measurements in optical fibers based on registration of Rayleigh scattering spectra. To describe the influence of spectral properties of optical radiation on the contrast of reflectograms, from which the spectra are formed. To indicate the advantages of using low-coherence radiation.

Result. An experimental installation of an OTDR with a low-coherence optical radiation source for distributed strain and temperature measurements has been designed. The main measurement mechanism in the proposed reflectometer scheme is registration of Rayleigh scattering spectra and their subsequent correlation analysis. The values of strain and temperature obtained experimentally using the reflectometer are in good agreement with the real values of these quantities.

Practical meaning. Devices built in accordance with the developed scheme can be used for SHM of infrastructure facilities.

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