“…It is observed that NRZ provides good result amongst another modulation format and system using NRZ format covered a distance of 190 km with good and viable results [1]. Investigation of Long haul high capacity DWDM system optical networks using nonreturn to zero (NRZ) format by making impact of optical pulse shape on transmission performance and characteristics [2]. Demonstration of 64×10Gbps and 96×10Gbps DWDM system using RAMAN-EDFA hybrid optical amplifiers with NRZ, RZ and DPSK modulation formats and it was found that RZ is more adversely affected by nonlinearities as compared to NRZ and DPSK which are more affected by dispersion [3].…”