Four by 622 Mb/s 40-km transmission experiment of wavelength-division multiplexing (WDM) system with erbium-doped fiber amplifier (EDFA)

A 4 X 622 Mb/s 40 km WDM optical communication system with EDFA is described. Four DFB-LD modules with 1.55 micrometers wavelength range are used in the transmitters. An EDFA with 1480 nm pump LD is used as a boost power amplifier. It suppresses noises efficiently. A Fabry-Perot interferometer is used as a demultiplexer. Through 40 km transmission, the output waveform of the receiver is obviously improved. It makes the research on long haul and WDM/FDM optical communication systems great progress.