The Study of gain-flattened hybrid EDFA/Raman Amplifier

• Main Authors: Chih-Ping Lan, 藍治平
• Other Authors: Jeng-Cherng Dung
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/k852g8

碩士 === 國立東華大學 === 電機工程學系 === 94 === Wide-band and gain-flattened fiber amplifier is a core device in WDM transmission systems. However, the bandwidth presently usable is limited to less than 30 nm due to the gain-bandwidth of conventional EDFA. Therefore, a wide-band hybrid amplifier, which can cover C- and L-band, will play an important role in the fiber communication system. Comparing to traditional Raman amplifier (RA), a hybrid Raman/EDFA amplifier, consisting of the EDFA at amplification band near 1530nm and Raman amplifier that could have the gain at any wavelength, can give us better performance and cost can also be reduced dramatically. In this thesis, we propose to use 50 km LEAF fiber as the gain medium of RA, and five types of Raman/EDFA hybrid amplifiers with different pumping direction and different order of EDFA and Raman amplifier will be discussed. Currently, we have built the wide-band hybrid optical amplifiers. The bandwidth of 96 nm with silica-based erbium-doped fiber combined with three-pumping wavelength for RA without any gain equalization filters. Note the performance comparison in this thesis under the five amplifier configurations in terms of gain, pump power, noise figure (NF). We have investigated the interplay between EDFA and Raman pump powers and four wave mixing (FWM) induced penalty in a hybrid amplified link. With signal input power of –20dBm, we get 2.05dB gain flatten and 1.14dB to 4.07dB NF and without FWM induced penalty in the optimum configuration that used EDFA in front of backward pumping RA.