Dispersion compensation in a 10 Gbit/s IM/DD semiconductor laser system in an NRZ scheme

A comparison between phase conjugation and dispersion shifted nonlinear compensating fibres, as methods for pulse dispersion compensation is performed by numerically studying the propagation of a 10 Gbit/s IM/DD signal over 100 km of singlemode fibre. Low-pass second order Butterworth filters are placed at the fibre input showing that the filter-induced chirp plays a crucial role in the propagation. The system performance is measured using the eye opening penalty (EOP) for several input powers, laser chirps and compensation lengths. The authors describe how the filters can produce pulse width reduction for certain distances and for some laser chirp parameters