Analyses on Gain-Equalized WDM Lightwave Systems

• Main Authors: Liang-Yih Chen, 陳良義
• Other Authors: Jen-Fa Huang
• Format: Others
• Language: en_US
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/23646327474570785090

碩士 === 國立成功大學 === 電機工程研究所 === 84 === Gain equalization is one of the major issues in implementing amplified wavelength-division-multiplexing (WDM) lightwave systems. This is due to the non-uniform wavelength-dependent gain profile and the saturation characteristics of erbium doped fiber amplifier (EDFA). In the long haul optical transmission system or subscriber networks, the non-flat gain spectra of cascaded EDFAs degrade system performances seriously. We study the model of EDFA and try to find optimum parameters (pump power, input signal level, amplifier length, etc.). The EDFAs have the largest gain and the smallest gain variation in multiple wavelength transmission. We estimate the gain variation between any two nodes in the long haul network. Static and dynamic WDM optical drop-add- multiplexers (W-DAM) are used to compensate wavelength- dependent gain of EDFA. Furthermore, W-DAM is insensitive to input signal level variation and pump power reduction. We find that, with 10dB range variation of input signal power, the output variation of W-DAM is only under 1dB.