Investigating the performance of apodized Fiber Bragg gratings for sensing applications

Abstract

Fiber Bragg gratings (FBGs) technology has demonstrated its suitability for many applications in recent fiber technologies. Sensing application is one of the main applications of FBGs. In this work, we present a comprehensive investigation for using apodized FBGs in sensing applications. Different evaluation parameters such as, reflectivity, sidelobes, and full-width-half-maximum (FWHM) are tested in order to determine the most proper apodization profile for sensors. According to our study, the Blackman apodization gives the best profile that can be used in sensing applications. The reflectivity of Blackman apodization is nearly unity with minimum sidelobes level, -60.3 dB, and narrow FWHM. The length of Blackman apodized FBG is 0.33 cm and Δn = 14.4 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">□4</sup> and maximum reflectivity is 99.44%.