Title :
Fiber Loop Mirror Sensors Interrogated and Multiplexed by OTDR
Author :
Miranda Rocco Giraldi, Maria Thereza ; Fernandes, Cindy Stella ; Ferreira, Marta S. ; de Sousa, Marco Jose ; Jorge, Pedro A. S. ; Weyl Albuquerque Costa, Joao Crisostomo ; Campos Oliveira Santos, Jose Luis ; Frazao, Orlando
Author_Institution :
Inst. for Syst. & Comput. Eng. of Porto, Porto, Portugal
Abstract :
In this paper, two techniques for interrogation and multiplexing of fiber loop mirror (FLM) intensity sensors based on optical time domain reflectometer (OTDR) are proposed. These configurations enable series and parallel FLM sensor interrogation. A fiber taper characterized as a displacement sensor was used as the intensity sensor. The OTDR parameters were optimized in order to obtain the best results. The optimized parameters were 100-ns pulse width and 10-dB input signal attenuation which permitted to attain ~18 dB dynamic range in the operating wavelength of 1550 nm. The results show a linear behavior for both configurations with similar slope, -15.3 dB/mm, in the normalized displacement range of 0.2 to 0.7 mm. It was also achieved a displacement resolution of 0.027 and 0.093 mm, for the series and parallel configurations, respectively. Sensors multiplexing are demonstrated for both configurations and the systems do not present crosstalk. Based on the experimental results, the best configuration is the parallel one. The proposed approach is a viable alternative for multiplexing and interrogation of remote fiber sensors.
Keywords :
displacement measurement; fibre optic sensors; mirrors; multiplexing; reflectometers; remote sensing; OTDR parameters; displacement resolution; displacement sensor; distance 0.027 mm to 0.093 mm; distance 0.2 mm to 0.7 mm; fiber loop mirror intensity sensors; fiber taper; input signal attenuation; normalized displacement; optical time domain reflectometer; parallel FLM sensor interrogation; remote fiber sensors; sensor multiplexing; series FLM sensor interrogation; wavelength 1550 nm; Multiplexing; Optical fiber sensors; Optical fibers; Optical reflection; Fiber loop mirror; Fiber loop mirror (FLM); OTDR; Optical fiber sensor; Sensor Interrogation; optical fiber sensor; sensor interrogation;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2014.2360500