Enhancement of measurement accuracy in fiber Bragg grating sensors by using digital signal processing

Summary form only given. The wavelength detection accuracy of fiber Bragg grating (FBG) sensors is limited by various types of optical noises. For systems which use broadband sources, the received signal power is usually low, resulting in a low signal-to-noise ratio, especially when time-division multiplexing is used to multiplex a large number of sensors. In sensor systems using laser sources, although the signal power is relatively much higher, residual reflections in the system may cause so-called interferometric noise, which would limit the wavelength detection resolution. In this paper, we report the results of our recent investigation on using a digital filtering technique for improving the wavelength detection accuracy in FBG sensors.