Comparison of EDFA and Raman amplifiers effects on RZ and NRZ encoding techniques in DWDM optical network with bit rate of 80 Gb/s

Abstract

Transmission of data through the communication networks is possible by using different methods of modulation and encoding. The aim of using these techniques is to efficiently use bandwidth and transmission of digital data by using carrier waves. There is no exception for optical communication systems in which we transmit optical pulses via the light waves. Yet, propagation of the light wave through the optical fibers would incur power loss due to different attenuation mechanisms. Such a situation will cause errors in detection of signals at the receiver end. So, to circumvent this problem, use of optical amplifiers is required. Erbium-doped fiber amplifier (EDFA) and Raman amplifier (RA) are the most popular ones, which are used widely in the optical communications systems. In this study, by simulating a DWDM optical link with a bit rate of 80 Gb/s and a link span of 80 km, the effects of EDFA and RA on NRZ and RZ encoding techniques for modulation are investigated by using Optisystem software solver and the received optical signals are analyzed by the corresponding eye-diagrams and Q-factors.