Digital Nonlinear Compensation for Spectrally Sliced Optical Receivers With MIMO Reconstruction

We experimentally investigate, in a 20×56-GBd 400 G WDM transmission system, different approaches for nonlinear compensation in spectrally sliced optical receivers with MIMO-based signal reconstruction. Slice-by-slice nonlinear compensation shows comparable performance to inter-slice nonlinear compensation in a WDM system. In addition, an eight-stages compensation yields a 0.4-dB Q2 gain equivalent to 250-km distance increase, resulting in 2000-km transparent reach.