The need for high capacity and bandwidth in broadband communication systems increased rapidly in a few past years. Optical fiber is now the major transmission medium for fast and reliable communication replacing the old copper-based connections. However, with the deployment of optical networks, number of problems arise. The main problem of optical networks is the amplification in the long-distance transmission. Erbium doped fiber amplifier (EDFA) is the leading technology in the field of optical amplifiers. It uses erbium doped fiber to amplify optical signal. The importance of amplification in optical domain is relevant in long-haul and high-speed transmission systems. In this paper the study of the EDFA is presented. Based on an analytical study, the simulation model of the EDFA is created. The main aim is to determine the optimal parameters of the EDFA for a long-haul 16-channel DWDM (Dense Wavelength Division Multiplexing) system. The performance of the proposed DWDM system is mathematically analyzed using BER (Bit Error Rate) and Q factor.
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