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Indexed by:Journal Papers

Date of Publication:2015-10-01

Journal:OPTICS AND LASER TECHNOLOGY

Included Journals:SCIE、EI、Scopus

Volume:73

Page Number:82-87

ISSN No.:0030-3992

Key Words:Fabry-Perot interferometer; Distributed temperature sensor; Incoherent optical frequency domain reflectometry

Abstract:A hybrid fiber-optic sensing technique, combining the extrinsic Fabry-Perot interferometer (EFPI) based pressure sensor with the incoherent optical frequency domain reflectometry (IOFDR) based distributed temperature sensor (DTS), is presented for down-hole measurements. By using a laser diode as the common light source, a highly integrated hybrid EFPI/DTS sensing system has been developed with a single fiber. With the injection current of the laser diode below lasing threshold, the broadband spontaneous emission light is used for EFPI based pressure sensing; while with the injection current above the threshold, the stimulated emission light is used for Raman based distributed temperature sensing. There is no overlap between the spectral range of the reflected light from the EFPI sensor and the spectral range of the Raman scattered light. Pressure and distributed temperature can thus be measured by using wavelength-division multiplexing (WDM) technology. Experimental results show that both the pressure and the distributed temperature are measured with little interference. Furthermore, the pressure measurement can be compensated by the measured temperature values. (C) 2015 Elsevier Ltd. All rights reserved.