Optical 2R regeneration using cascaded fiber four-wave mixing with suppressed spectral spread

A fiber four-wave mixing (FWM)-based all-optical reshaping and reamplifying (2R) regeneration technique with near-ideal step-like transfer function and suppressed spectral spread is proposed. By setting proper phase modulation conditions and wavelength relations in a two-stage cascaded FWM approach, we succeeded in nearly spectral-spread free 2R regeneration, and demonstration of improved performance for 10-Gb/s nonreturn-to-zero pseudorandom binary sequence data transmission.