4-wavelength 2R regeneration based on self-phase modulation and inter-channel walk-off control in bidirectional fiber configuration

We propose a novel multi-wavelength regeneration scheme in which timing walk-off on different WDM channels is controlled to avoid the overlapping of the channels in time domain such that effective mitigation of the nonlinear inter-channel impairments can be obtained, and the number of supported channels in the regeneration is increased by applying a bidirectional fiber configuration. In our scheme, optical 2R regeneration is successfully demonstrated for four 10-Gb/s RZ-OOK WDM channels spaced by 300 GHz. Both the scalability and the cascadability of our proposed regenerator were also evaluated in numerical simulations.