Fig. 5

Experimental demonstration of simultaneous regeneration of 8 and 16 WDM DPSK channels. a Experimental setup of 8× and 16× 10 Gbit/s DPSK WDM regeneration. At the transmitter: 8- or 16-CW carriers are generated by individual CW lasers, and are DPSK modulated by in a MZM. The obtained WDM channels are data decorrelated in a 4-path decorrelator, and are then sent to the optical WDM regenerator. Phase noise is added using a phase modulator driven by broadband electrical noise. At the receiver: after WDM demultiplexing, the regenerated WDM channels are received by a pre-amplified DPSK receiver including a DI and balanced photo-detection. b WDM regenerator, a 100-ps DI is used convert all WDM DPSK channels (S1) to OOK signals, which are then converted to a 80-or 160-GBd serial signal by the first OFT (S2). The obtained serial OOK signal (upper S3) is coupled into the HNLF as an XPM pump to optically phase modulate the pulsed XPM probe (S4). The pulsed XPM probe is generated from carving the CW carrier S using a NPRL. A single PSA (S5) is employed for phase regeneration of the obtained serial DPSK signal. Finally, the regenerated serial signal is converted back to WDM signals by the second OFT (S6) using a 90-ps pump pulse (lower S3). c Spectrum of the input WDM channels (S1), 1st OFT output spectrum (S2), waveform of the 80 GBd OOK signal (upper S3), waveform of the 2nd OFT pump (lower S3), waveform of the coherent pulse (S4), output spectrum of the PSA (S5), 2nd OFT output spectrum (S6)