Time division multiplexing of fiber Bragg grating sensors using a mode-locked fiber laser source (Invited Paper)

An efficient multiplexing method for fiber Bragg grating sensors based on a broadband mode-locked laser source and interferometric interrogation is described. The system has the capability to interrogate several hundred fiber Bragg grating sensors on a single fiber, whilst achieving sub-microstrain resolution over bandwidths greater than 100 kHz. A demonstration system with 8 sensors is presented, which achieves strain resolutions less than 213 nε/Hz1/2 up to 100 Hz.