INTERROGATION OF WAVELENGTH CODED PHASE SIGNALS IN DIGITAL SPATIAL DOMAIN FOR OPTICAL FIBRE SENSING APPLICATIONS

摘要

A new technique to interrogate wavelength coded phase signals in digital spatial domain for optical fibre sensing applications is reported. It can integrate a large number of sensing fibres and as well as wavelength channels into a simple, robust and low cost system. Preliminary experiments of interrogating dual-wavelength coded signals with two narrowly spaced wavelengths to trace fast varying strains and increase the measurement bandwidth of the system has shown the feasibility of the technique. The technique could, in principle, also be used to discriminate environmental temperature from strain signals when two widely spaced wavelengths are employed. [References: 6]