Origins of Cross-Phase Modulation Impairments in Optical Transmission Systems Without In-Line Dispersion Compensation

The origins of cross-phase modulation (XPM) impairments in optical transmission systems with wavelength-division multiplexing (WDM) at 10 Gbit/s using intensity modulation are studied. We investigate the impact of a co-propagating signal's predistortion and the impact of the underlying dispersion map separately by using modified pump-probe system setups. We find that the dispersion map mainly determines the system's susceptibility to XPM, whereas an increasing predistortion does not result in higher XPM impairments of the system.