This paper proposes a system that aims to reduce the spectral width, Δλ, of the optical signal at transmitter for WDM system over distance 100 km. Also, a chirped fiber Bragg grating (CFBG) at the receiver is used to compensate dispersion. The proposed system consists of four cascaded FBGs connected between light source and optical fiber. Many apodization functions are investigated to enhance the performance of the FBG in the proposed system, and Δλ is obtained at every stage and apodization function. The Q-factor and bit error rate (BER) are obtained at distances 30, 40 and 50 km. It is found that Cauchy apodization function is the best one that reduces the reflective spectral width, Δλ, and achieves a maximum Q-factor and minimum BER at distances 30, 40 and 50 km at the last stage.

本文提出了一种旨在减小WDM系统在100 km距离上的发射器处光信号的光谱宽度Δλ的系统。同样，接收器处的a光纤布拉格光栅（CFBG）用于补偿色散。拟议的系统由连接在光源和光纤之间的四个级联FBG组成。研究了许多切趾函数以增强所提出系统中FBG的性能，并且在每个阶段都获得了Δλ和切趾函数。在距离30、40和50 km处获得Q因子和误码率（BER）。发现柯西切趾功能是减小反射光谱宽度Δλ并在最后阶段在距离30、40和50 km时实现最大Q因子和最小BER的最佳功能。