Wavelength Division Multiplexing

WDM (Wavelength Division Multiplexing) technology refers to the use of multiple laser beams in the same fiber simultaneously transmit multiple wavelengths of light technology. It can greatly improve the transmission capacity of optical fiber transmission system.

Currently, 1.6 Tbit/s WDM system has been large-scale commercialization. In order to further improve the transmission capacity of DWDM (Dense Wavelength Division 1995 Multiplexing) foundation has become the international main research object, Lucent Baer laboratory capacity DWDM system that can be up to 100 Tbit/s commercial.

At present, the 10 Gbit/s based DWDM has gradually become the mainstream of the core network in a number of carriers in china. In addition to the wavelength and transmission capacity increasing, the optical transmission distance increases from 600 km to more than 2000 km in DWDM system.

In addition, the coarse wavelength division multiplexing CWDM (Coarse Wavelength Division Multiplexing) also came into being in the metropolitan area optical transmission network expansion, with the advantages of large capacity, short distance transmission and low cost. The researchers also found that a number of optical time division multiplexing OTDM signal wavelength division multiplexing can greatly improve the transmission capacity. As long as the appropriate combination can achieve more than Tbit/s transmission, therefore, it has become the future direction of development of optical fiber communications. Most of the experiments in the laboratory, more than 3 Tbit/s, are implemented in this way.