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Updated: May 28, 2026

Fiber Optic Distributed Sensors for High-resolution Temperature Field Mapping
Published on: November 7, 2016
Ultralong 250 km remote sensor system based on a fiber loop mirror interrogated by an optical time-domain
M Bravo1, J M Baptista, J L Santos
1Departamento Ingeniería Eléctrica y Electrónica-Universidad Pública de Navarra, Pamplona, Spain. mikel.bravo@unavarra.es
Abstract:
A 253 km ultralong remote displacement sensor system based on a fiber loop mirror interrogated by a commercial optical time-domain reflectometer is proposed and experimentally demonstrated. The use of a fiber loop mirror increases the signal-to-noise ratio, allowing the system to interrogate sensors placed 253 km away from the monitoring system without using any optical amplification. The displacement sensor was based on a long period grating spliced inside of the loop mirror, which modifies the mirror reflectivity accordingly to the applied displacement.

