Investigation of Cross-Phase Modulation-Induced Transmission Penalties Using the Pump-Probe Technique

The cross-phase modulation effect and the resulting induced distortion in single-mode optical fiber are investigated in multichannel systems. A simple technique is described to estimate the impact of cross-phase modulation on WDM transmission penalties. The induced distortion build-up is characterized as a function of channel spacing and distance in pump-probe experiments. These experiments and analytical calculations are used to predict the contribution of XPM distortion to the total transmission penalty as a function of distance and wavelength spacing for N×10 Gbit/s WDM systems. The accuracy of this method is demonstrated by a comparison with direct BER measurements at 10 Gbit/s using a recirculating fiber loop.