Tunable Optical Parametric Regenerator Assessment in a 43 Gb/s RZ-DPSK Signal Transmission Link

We study a wavelength-tunable optical parametric regenerator (OPR) demonstrated experimentally by assessing numerically its performance as an inline component of a 43-Gb/s return-to-zero differential phase-shift keying transmission system. The device features wide input wavelength range operation and regenerative wavelength conversion. The improvement in the transmission reach that it provides is predicted by simulations benchmarked against the experimental data. An up to fourfold improvement at a bit error ratio of ~ 10^-4 is estimated for a 360-km long regeneration span. We show that the improvement is achieved by a combination of the amplitude regeneration capabilities with the phase noise blocking character of the OPR, despite of the small amount of phase fluctuations induced by the regenerator itself.