• Submit to Sensors Login Register
• MDPI
• Journals A-Z
• For Authors
• For Editors
• About
• Open Access Policy

• Abstract
• Full-Text PDF [596 KB]
• Full-Text XML
• Article Versions Notes

• Article Statistics
• PubMed/Medline
• Google Scholar
• Order Reprints

• Cite this article
• Export to BibTeX
• Export to EndNote

• [+] on DOAJ
• Zhang, Z
• Yan, L
• Pan, W
• Luo, B
• Wang, P
• Guo, L
• Zhou, W
• [+] on Google Scholar
• Zhang, Z
• Yan, L
• Pan, W
• Luo, B
• Wang, P
• Guo, L
• Zhou, W
• [+] on PubMed
• Zhang, Z
• Yan, L
• Pan, W
• Luo, B
• Wang, P
• Guo, L
• Zhou, W

•  CiteULike
•  Facebook
•  Mendeley
•  Twitter

This article is

• freely available
• re-usable

Sensors 2012, 12(4), 3891-3900; doi:10.3390/s120403891

Article

Sensitivity Enhancement of Strain Sensing Utilizing a Differential Pair of Fiber Bragg Gratings

Zhiyong Zhang ¹ , Lianshan Yan ^1,* , Wei Pan ¹ , Bin Luo ¹ , Ping Wang ² , Likang Guo ²  and Wei Zhou ¹

¹ Center for Information Photonics & Communication, School of Information Science and Technology, Southwest Jiaotong University, Chengdu, Sichuan 614202, China ² Lab of Railway Engineering, School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan 614202, China

* Author to whom correspondence should be addressed.

Received: 16 February 2012; in revised form: 28 February 2012 / Accepted: 5 March 2012 / Published: 26 March 2012

(This article belongs to the Special Issue Optical Fiber Sensors)

Download PDF Full-Text [596 KB, uploaded 26 March 2012 14:49 CEST]

Abstract: In strain measurement applications, the matched fiber Bragg gratings (FBG) method is generally used to reduce temperature dependence effects. The FBG parameters have to be designed to meet the requirements by the particular application. The bandwidth and slope of the FBG has to be balanced well, according to the measurement range, accuracy and sensitivity. A sensitivity enhanced strain demodulation method without sacrificing the measurement range for FBG sensing systems is proposed and demonstrated utilizing a pair of reference FBGs. One of the reference FBGs and the sensing FBG have almost the same Bragg wavelength, while the other reference FBGs has a Bragg wavelength offset relative to the sensing FBG. Reflected optical signals from the sensing FBG pass through two reference FBGs, and subtract from each other after the detection. Doubled strain measurement sensitivity is obtained by static rail load experiments compared to the general matched grating approach, and further verified in dynamic load experiments. Experimental results indicate that such a method could be used for real-time rail strain monitoring applications.

Keywords: fiber Bragg grating; strain measurement; differential pair of FBG; sensitivity; railway safety monitoring

Article Statistics

Cite This Article