CWDM – how to meet the growing demand for low-cost multi-channel transmission

Abstract:
Cost-effective short-haul but high-capacity optical transport systems are becoming increasingly important for metropolitan-area and access applications; examples are metro-feeders, inter- or intra-office links between routers and cross-connects, and storage-area networks. Typically, such links cover transmission distances between 20 and 80 km with 4, 8 or more channels and connect the broadband access part to the metro-regional and long-haul sections of the network. Due to the inherent wavelength drift of low-cost uncooled components such as directly-modulated lasers, full spectrum CWDM is defined for up to 16 or 18 channels on a 20-nm wavelength grid between 1270/1310 and 1610 nm.