The investigation of the parameter choice of the nonlinearly chirped FBG

Abstract

Purpose

Correctly choosing the nonlinearly chirped fiber Bragg grating (NLCFBG) parameter is very important, which may instruct the effective manufacture grating. The purpose of this paper is to analyze some kinds of curve reflection spectrums and time delays of the FBG.

Design/methodology/approach

In this paper, some kinds of curve reflection spectrums and time delays of the FBG are analyzed. The paper makes the numerical simulation of the spectrum character and time delay about some kinds of FBG. The relation between the modulation intensity and linear chirp coefficient c₁ of the FBG is studied for the first time. The transformation of the curve about time delay is compared at different modulation intensity.

Findings

The authors investigate the number of dots which is used to draw a graph of the spectrum character and time delay, and is found that the graph of the spectrum character and time delay is broken off when the graphed number of dots is too less. Also, the authors study the reflection spectrum of the NLCFBG, when the segment number M of NLCFBG is less, the graph of reflection spectrum of the NLCFBG is fuzz.

Research limitations/implications

Attention should be paid to coordination among the parameters of the NLCFBG.

Practical implications

The paper provides very useful advice for highly efficient production of the gratings.

Originality/value

The following new viewpoint is proposed: the longer the length of the NLCFBG, the smaller its numerical value of the NLCFBG parameters c₁, c₂ and modulation intensity. This paper is aimed at guiding the correct production of the gratings.

Citation

Xianjie, F., Shengqian, W. and Daowen, Z. (2010), "The investigation of the parameter choice of the nonlinearly chirped FBG", Kybernetes, Vol. 39 No. 6, pp. 915-924. https://doi.org/10.1108/03684921011046681