A novel distributed fiber optic strain sensor
The theory of operation of a fiber optic-based strain sensor system, suitable for long structures, is described. The proposed sensor design is composed of several hundreds of sections separated by reflectors in order to monitor structures of more than one kilometer of length. A quasi distributed sensor structure accomplishes best condition monitoring where each section of the sensor integrates the measured magnitude, obtaining a value associated to the average shortening or elongation in this section. Tools for the design of the optical reflectors of the sensor are also provided, including a study of the optical noise due to multireflection within the system.