Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/5293
Title: Recent progress in bidirectional interrogation techniques for enhancing multiplexing capability of fiber optic white light interferometric sensors
Authors: Yuan, Libo
Zhou, Limin
Jin, Wei
Subjects: Fibre optic sensors
Optical arrays
multiplexing
Strain sensors
Temperature sensors
Distributed sensors
Intelligent sensors
Michelson interferometers
Mach-Zehnder interferometers
Issue Date: Nov-2003
Publisher: American Institute of Physics
Source: Review of scientific instruments, Nov. 2003, v. 74, no. 11, p. 4893-4898.
Abstract: In smart structure applications where fiber sensors are embedded within structural materials, multiple lead in/out fibers are preferred for redundancy and improving reliability. The use of only one lead/out fiber is not optimal because the breakage of a fiber at one location due to, for example, local structural damage, would cause the failure of the whole sensing system. The multiplexing and networking techniques suitable for such applications have attracted considerable research recently. In this article, based on the bidirectional interrogation technique for white light interferometric sensors arrays, a multiplexed fiber optic deformation sensor loop network suitable for smart structure applications has been designed and demonstrated. Loop-network sensor systems are based on the white light interferometric technique. Michelson and Mach–Zehnder optical path interrogators have been developed and demonstrated, respectively. For the usually used one direction interrogate sensing system, it is clear that multiplexed sensor arrays suffer from relatively large fiber segment-induced optical reflective and excess insertion loss that generally limit the total number of sensors that can be accommodated in this configuration. This loop-network bidirection interrogating technique greatly extended the multiplexing capacity of fiber optic white light interferometric sensors system. A practical implementation of this technique is presented which makes use of a popular light emitting diode, superluminescent diode, or amplified spontaneous emission optical light source and standard single mode fiber, which are commonly used in the communication industry. The sensor loop topology is completely passive and absolute length measurements can be obtained for each sensing fiber segment so that it can be used to measure quasidistribution strain or temperature. For large-scale smart structures, this technique not only extends the multiplexing potential, but also provides a redundancy for the sensing system. It means that the sensor loop permits one point breakdown, because the sensing system will still work whenever the embedded sensor loop breaks somewhere.
Rights: © 2003 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in L. Yuan, L. Zhou & W. Jin, Review of scientific instruments 74, 4893 (2003) and may be found at http://link.aip.org/link/?rsi/74/4893
Type: Journal/Magazine Article
URI: http://hdl.handle.net/10397/5293
DOI: 10.1063/1.1614434
ISSN: 0034-6748 (print)
1089-7623 (online)
Appears in Collections:EE Journal/Magazine Articles
ME Journal/Magazine Articles

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