With the rapid development of the access network, the bandwidth demand has doubled, the core network has begun to step into the application, but the bandwidth of the metropolitan area network is not enough to develop. However, with the increasing tension in the optical fiber resources, the cost of the new optical cable in the urban area is becoming more and more expensive, and the construction of the metropolitan network needs a cheaper solution. So WDM technology emerges as the time requires, using multiple wavelengths in single fiber bearing service, making full use of available broadband and saving cost, mainly in the medium and short distance optical metropolitan area network.

CWDM SYSTEM