High-speed tunable FDML laser, interfaced to a continuous FPGA acquisition system, for FBG accelerometer interrogation

In this study, we have developed a FDML laser characterized by a scanning frequency up to 100 kHz over a wide spectral range of several tens of nm at 1.55 μm. Traditionally, high speed FBG analyzers able to demultiplex arrays of Fiber Bragg Gratings do not process the data continuously. To overcome this limitation, our FDML laser has been interfaced with a continuous data acquisition system based on a 250 MS/s 4-channels FPGA board. This paper presents the main characteristics of this new optoelectronic interrogation system and the results obtained when scanning an FBG accelerometer at 20.3451 kHz and 61.053 kHz.