Temperature measurement of overlapped fiber Bragg grating sensors in a series fiber sensor network

Abstract

Fiber Bragg Gratings (FBGs) in a sensor network have been widely used for structural health and process monitoring. The number of FBGs with distinct wavelength that can be used in such a sensor network is limited by the bandwidth of the laser used. FBGs, with overlapping spectra cannot be interrogated in a series sensor network since they shadow each other. Methods like time division multiplexing (TDM), code division multiplexing (CDM) have been used to interrogate overlapped FBGs. TDM is limited by the power budget system and CDM is limited by the number of FBGs can be used. We propose a neural network based Spectral Division Multiplexing (SPDM) scheme, to monitor overlapped FBGs in a series fiber sensor network.

Keywords

• Fiber Bragg Gratings
• Structural health monitoring
• Process monitoring
• Time division multiplexing
• Code division multiplexing
• Power budget system