Extinction ratio improvement using the regenerative properties of four-wave mixing

This work proposes a simple and efficient technique to improve the extinction ratio of a transmitter by using the regenerative properties of four-wave mixing (FWM) in a highly non-linear dispersion shifted fiber. We developed a theoretical model that shows the possibility of a 3 dB increase in the optical transmitter extinction ratio, which is an important design parameter. The numerical simulations confirm the theoretical model and reveal that there should be a trade-off among fiber and systems parameters to avoid eye closure penalty.