1.7 Gbit/s, 1.5 mu m coherent lightwave regenerator

The operation of a practical and complete 1.7 Gbit/s coherent lightwave regenerator at lambda =1.5 mu m is reported. The regenerator is housed in a standard AT&T repeater shelf and consists of five plug-in subsystem modules including an FSK transmitter, a local oscillator laser, a polarisation diversity receiver, a ´cold start´ AFC circuit and a 1.7 Gbit/s regenerator. The system has a receiver sensitivity, eta P, for 10^-9 of -41.5 dBm, and a power penalty caused by polarisation fluctuation of less than 0.7 dB. Long term (>60 h) error free performance (BER>10^-14) was achieved through a 200 km fibre length with a receiver sensitivity of -39 dBm.