Influence of Dispersion Compensation Granularity on the XPM-Induced Degradation in NRZ-IM-DD WDM Links at 10 Gbit/s per Channel with 50 GHz of Channel Spacing

The influence of the dispersion compensation granularity on the cross-phase modulation (XPM) induced degradation in non-return-to-zero intensity modulated with direct detection wavelength division multiplexed links at 10 Gbit/s per channel with 50 GHz of channel spacing is assessed analytically for different power levels and four dispersion maps. The dispersion compensation granularity may lead to an increase of the power penalty due to XPM exceeding 1.5 dB for the locally optimal dispersion map (from the XPM degradation viewpoint) with high positive residual dispersion per span. The increase of the XPM normalized variance due to the dispersion compensation granularity is higher for links showing noticeable XPM degradation in the absence of dispersion compensation granularity. Lower XPM degradation tolerance to the dispersion map variation and higher power level leads to higher XPM degradation due to the dispersion compensation granularity.