Capacity and capability enhancements of FBG sensor system by utilizing intensity and WDM detection technique

Abstract

In this paper, we demonstrate a multipoint fiber Bragg grating (FBG)-based sensor system by using intensity and wavelength-division-multiplexing (I-WDM) technique to enhance the sensing capacity and capability. In the proposed multipoint sensor system, a three output port optical splitter with different output ratios of 50%, 35% and 15% is proposed to connect each intensity coding FBG sensor for strain and temperature sensing simultaneously. Different output ratios of connected ports can produce different intensity-coding for I-WDM application. Nine FBGs with different Bragg wavelengths are employed for demonstration. The proposed FBG sensor system not only can sense the strain and temperature simultaneously, but also can increase the capacity and capability.