Distributed temperature sensing via Brillouin-tailored optical fiber

Peter D. Dragic

doi:10.1117/12.818810

27 April 2009 Distributed temperature sensing via Brillouin-tailored optical fiber

Peter D. Dragic

Proceedings Volume 7316, Fiber Optic Sensors and Applications VI; 731605 (2009) https://doi.org/10.1117/12.818810
Event: SPIE Defense, Security, and Sensing, 2009, Orlando, Florida, United States

Abstract

We present Brillouin-tailored optical fiber for use in distributed temperature sensing systems. A manufactured fiber operates with two Brillouin modes that have been gain-equalized to within 0.5 dB, with frequency difference of 175 MHz. Some traditional distributed systems employ a heterodyne scheme to measure a temperature-dependent microwave frequency Stokes' shift (~11 GHz at 1530 nm) imparted by Brillouin scattering. Realizing an RF detection scheme for the temperature distribution may include the development of an optical fiber engineered to have two gain-equalized Brillouin frequencies. The two acoustic modes should respond differently to temperature variations, and thus the detection of their beat signal would provide temperature data. One approach investigated is to structure the core to have two or more dissimilar layers that are 'quasi-independent' such that their resulting Brillouin frequencies are far enough apart, and have a significantly dissimilar dependence on temperature. Gain equalization between these two modes results from the proper tailoring of the overlap integrals with the optical mode. Our best results were achieved through core-cladding Brillouin-gain equalization via the reduction of Brillouin gain in the core of a tailored fiber. A linear temperature dependence of -1.1 MHz/°C was measured for the beat frequency of a developed fiber.

Citation Download Citation

Peter D. Dragic "Distributed temperature sensing via Brillouin-tailored optical fiber", Proc. SPIE 7316, Fiber Optic Sensors and Applications VI, 731605 (27 April 2009); https://doi.org/10.1117/12.818810

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available