Multi-point in-fibre grating strain sensing system with a combined spatial and time division multiplexing scheme

We have demonstrated a combined spatial- and time division multiplexing topology with drift-compensated high-resolution wavelength-shift detection for a fibre Bragg grating (FBG) sensor system. An eight-element grating sensor array based on this topology is demonstrated although the network can support 16 FBG sensors without affecting the signal-to-noise ratio of each sensor. A range-to-resolution ratio of 1250:1 for quasi-static strain measurement has been achieved with a measurement bandwidth of 30 Hz