1.2 Gbit/s optical DPSK heterodyne detection transmission system using monolithic external-cavity DFB LDs

The feasibility of using solitary LDs as light sources for a Gbit/s range optical DPSK heterodyne detection system has been confirmed in 1–2 Gbit/s transmission experiments. With monolithic external-cavity DFB LDs, a receiver sensitivity of — 43dBm and transmission over 152 km have been achieved. With conventional discrete external-cavity LDs, — 45dBm and 170 km have also been achieved.