Optimization of the Available Spectrum of a WDM Sensors Network Using a Mode-Locked Laser

This paper experimentally proposes a new interrogation method which consists of the combination of the information given by both domains: time and frequency. On the one hand, the sensor information is obtained in the frequency domain as usual and, on the other hand, the detection of the different pulses generated through mode locking allows the identification of each fiber Bragg grating (FBG). It has been proved that FBGs spaced less than 0.15 nm can be interrogated. The sensor network based on simple ring Erbium-doped fiber laser using the FBGs, located in a serial configuration, as wavelength selective reflectors for the lasing structure, acting them also as the sensing transducers elements.