2-CHANNEL COHERENT OPTICAL FDM TRANSMISSION-SYSTEM WITH A NEW FREQUENCY STABILIZATION SCHEME

A two-channel 140 Mbit/s coherent optical FDM transmission system with a new frequency stabilisation scheme has been developed. In this scheme, low frequency modulation is applied to transmitter laser diodes to lock them at the resonances of a Fabry-Perot interferometer, and a high speed IF AFC circuit is used to eliminate the system performance degradation due to this low frequency modulation. The measured BER is 10-9 for a received signal power of -41 dBm and no crosstalk between channels is observed with a channel spacing of 4.0 GHz.Engineering, Electrical & ElectronicSCI(E)EI2ARTICLE5310-3122