Abstract

We report a new technique for demodulation of wavelength division multiplexed fiber laser sensor arrays. It utilises pseudo-random phase coding at the interferometric detection stage and high speed digital signal processing to enable demodulation of multiple sensor channels on a single physical detection and digitisation channel. This archi- tecture has the capacity to greatly reduce the physical size and complexity of the detection system for large arrays. Near thermal noise limited strain sensitivity is demonstrated for a two channel system over a 2 kHz acoustic bandwidth with a data acquisition rate of 1MHz.

© 2020 The Author(s)