Design of a large-capacity fiber Bragg grating demodulation system based on modulated grating Y-branch tunable laser

To achieve synchronous demodulation of a large-capacity Fiber Bragg Grating (FBG) sensor network, a FBG demodulation system based on modulated grating Y-branch (MG-Y) tunable laser is designed, combining wavelength division multiplexing and space division multiplexing technologies. The system consists of MG-Y tunable laser control module and FBG reflection spectrum acquisition module. By calibrating the MG-Y tunable laser, it can output quasi-continuous light with a bandwidth of 40nm and wavelength spacing of 20pm to meet the requirements of wavelength division multiplexing technology. In terms of space division multiplexing technology implementation, the spectrum acquisition module is designed for 16 channels. Finally, experiments were conducted using an Fabry-Perot (F-P) etalon to validate the functionality of the system.