20 Gbit/s TDM nonrepeatered transmission over 198 km DSF using Si-bipolar IC for demultiplexing and clock recovery

Results are reported of a 20 Gbit/s TDM transmission through 198 km of dispersion shifted fiber (DSF) without inline amplifiers. For a receiver we used a demultiplexer and clock recovery unit. A new decision circuit with combined phase detection is used. With an optical preamplifier a receiver sensitivity of -30.5 dBm has been achieved.