Temperature-strain discrimination using a wavelength-division-multiplexed chirped in-fibre-Bragg-grating/extrinsic Fabry-Perot sensor system

In this letter, we present a novel sensor approach allowing fast measurement of temperature. It consists of a chirped fibre Bragg grating (CFBG) and an extrinsic Fabry-Perot interferometric sensor (EFPI) in series. Both EFPI and CFBG are well integrated to provide local strain and temperature information respectively, using wavelength-division-multiplexed (WDM) technique. As the wavelength-shift of the CFBG is detected via intensity variation, the speed for temperature measurement can be very high (<0.1 ms). Also, there is little cross-talk between the CFBG and the EFPI due to the introduction of WDM.