1 Scope
This part of IEC 61757 defines the terminology, structure, and measurement methods of distributed fibre
optic sensors for absolute strain measurements based on spectral correlation analysis
of Rayleigh backscattering signatures in single-mode fibres, where the fibre is the
distributed strain measurement element in a measurement range from about 10 m to tens
of km. This document also applies to hybrid sensor systems that combine the advantages
of Brillouin and Rayleigh backscattering effects to obtain optimal measurement quality.
This document also specifies the most important features and performance parameters
of these distributed fibre optic strain sensors and defines procedures for measuring
these features and parameters.
This part of IEC 61757 does not apply to point measurements or to dynamic strain measurements. Distributed
strain measurements using Brillouin scattering in single-mode fibres are covered in
IEC 61757‑1‑2 .
The most relevant applications of this strain measurement technique are listed in
Annex A, while Annex B provides a short description of the underlying measurement principle.
Open preview (PDF)Fibre optic sensors - Strain measurement. Distributed sensing based on Rayleigh scattering