STM32F4 based real-time peak detection of FBG

A low-cost and compact FBG demodulator is demonstrated and high efficiency peak detection method is implemented for it. A low-cost Tunable laser is used as light source, so bulky and often expensive light dispersion device is not needed. Low-cost and compact STM32F4 embedded ARM system is used to acquire data and to detect the peak. High efficiency Gaussian curve fitting method based on Levenberg-Marquardt (LM) algorithm was developed to detect the peak wavelength. The demodulation time is only 70ms. The uncertainty of the peak detection is 0.87 pm when the tuning stop is 10pm. It it is suitable for field use where real-time measurement is needed.