10 Gbit/s optical PSK homodyne transmission experiments using external cavity DFB LDs

10 Gbit/s optical PSK homodyne transmission experiments using a modified decision-driven optical phase locked loop with 1.55 μm external cavity laser diodes were conducted. A receiver sensitivity of −34.2 dBm or 297 photon/bit was experimentally achieved. There was no degradation in receiver sensitivity after signal transmission through 151 km of dispersion shifted fibre.