DPSK signal regeneration using a fiber-based amplitude regenerator

An experiment of an all-optical DPSK-signal regeneration is reported. In the regenerator, incoming DPSK signals are first demodulated to on-off-keying signals, then amplitude-regenerated by a 2R regenerator, and subsequently used as control pulses for phase remodulation of clock pulses in an all-optical phase modulator. Penalty-free operation with reduced amplitude noise is demonstrated by the use of a two-stage fiberbased cascaded 2R amplitude regenerator in bidirectional configuration.