Stable multiwavelength fiber laser for referencing intensity sensor networks using multiple amplified ring resonators

An experimental comparison of the stability performance of two different optical multiwavelength lasers is shown based on erbium highly doped fiber amplification. The two laser structures compared were: a star configuration using a 2x4 coupler to extract the signal from the ring to 4 FBGs and a structure with 4 active ring resonators that use both the same pump laser. Both lasers use Fiber Bragg gratings (FBG) to select the operation wavelengths within the resonant ring cavity. The stability of this new laser is compared with the achieved by a single ring configuration. The improvement of both stabilities depending on the time and temperature for the new structure was experimentally demonstrated. The utilization of the new configuration for multiplexing optical fiber sensors has also been carried out. The sensors provide amplitude modulation in response to the curvature introduced by a temperature-sensitive element. Each sensor is identified by a different wavelength generated by each FBG. The signal generated by the grating firstly is used as reference signal ant secondly is launched towards the sensors and the transmitted signal is measured. The sensors show a stable and linear response when measurements are carried out using simultaneously all the outputs of the structure for transmitting the multiple wavelengths to the sensors and utilizing the serial referencing output of the laser.