Loop Topology Based White Light Interferometric Fiber Optic Sensors Network

Abstract

Based on the one loop network technology, a coupled dual-loop network bidirection interrogating technique has been developed and demonstrated. A practical implementation of theses coupled dual-loop schemes is configured by use of a popular ASE light source and standard single mode fiber, which are commonly used in communication industry. The sensor dual-loop topology is completely passive and absolute length measurements can be obtained for each sensing fiber segments so that it can be used to measure quasi-distribution strain or temperature. For the large-scale smart structures, this technique not only extends the multiplexing potential, but also provides a redundancy for the sensing system. It is mean that the coupled dual-loop sensors network permit two points breakdown, because the sensing system will still work whenever the embedded dual-looped sensors has been destroyed in somewhere. The robustness of the 9-sensor coupled dual-loop sensing network are discussed and demonstrated in our experiments. The intensity characteristic of the output signal of the interferometer is analyzed and verified by the experimental results.