Comparison between DWDM Transmission Systems over SMF and NZDSF with 25×40Gb/s signals and 50GHz Channel Spacing

The use of new types of fibre with high density and high capacity dense wavelength division multiplexing (DWDM) systems leads to the investigation of system performance with these fibres. This paper compares the performance of a high-density (0.8bits/s/Hz) DWDM transmission system with 25 channels and 40Gb/s per channel with a channel spacing of 50GHz, using conventional single-mode fibre or non-zero dispersion shifted fibre (NZDSF). For this, semi-analytical simulation of the DWDM system is performed using rigorous models for optical multiplexer and external modulator. Nonlinear transmission phenomena in the fibre are also included in the simulation. The results show that NZDSF allows significant extension of reachable distances with dispersion compensation and in-line amplification.