Sensor network based on multiplexed intermodal fiber interferometers for quasi-distributed measurements

An implementation of a sensor network based on several multiplexed intermodal fiber interferometers (IFIs) has been presented. The use of a few-mode fiber and spectral interrogation in combination with the Fourier analysis of sensor network signals were shown to provide a linear response of each IFI to an external impact. We have developed a physical-mathematical model of the sensor network and applied it to study three IFIs multiplexing options-serial, parallel, and combined. The best signal-to-noise ratio was found to achieve by a combined multiplexing scheme. The sensor network with combined multiplexing of six IFIs was implemented and investigated experimentally. We demonstrated experimentally that this sensor network provides a linear response for each IFI with a crosstalk level of no more than 5%.