A Study on Apodization Profiles of Fiber Bragg Gratings

Abstract

In this paper, a theoretical and numerical validation of the effects of apodization over the fiber Bragg grating spectrum is presented. A FBG is an optically induced periodical perturbation, which produces Bragg wavelength on the input side, depending upon the refractive index and grating period. The reflected wavelength contains side lobes that can interfere in FBG�s operational capabilities, but they can be mitigated by employing tailoring of refractive index, i.e., apodization. This overview presents various apodization functions such as Sinc, Nuttall, and others. A quantitative analysis is also presented by computing the bandwidth, i.e., full width half maxima points (FWHM), side lobe peak level (SLPL), and percentage change in first side lobe�s peak value. Continuing with numerical analysis, it has been observed that Nuttall and Sinc function provide better side lobe suppression capabilities as compared to other functions, with the percentage change in peak side lobes values of 30.38 and 10.94, respectively. � 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.