DWDM stands for “Dense Wavelength Division Multiplexing” and allows per definition up to 40/80 DWDM wavelengths over one pair of fiber.
- Up to 90 DWDM wavelength over one pair of fiber
- DWDM channel spacing 0.8 nm (100 GHz grid) or 0.4 nm (50 GHz grid)
- Distances over 1,000 km can be achieved with the use of optical amplifier
- DWDM wavelength: 1528 nm (channel 61) to 1563 nm (channel 17)
The functionality of DWDM resembles to the one of CWDM. Unlike to CWDM technology, the channel spacing for DWDM is 0.8/0.4 nm (100 GHz/50 GHz grid). This small channel spacing allows to transmit simultaneously much more information. Currently a restriction on wavelengths between 1530 nm and 1625 nm exists which corresponds to the C and L band. In this connection DWDM wavelengths from DWDM technology is more expensive compared to CWDM caused by the need of more sophisticated transceivers.
Theoretically available DWDM channels in the C and L-band
depending on the channel spacing
• ITU-T G.694.1
• C-Band λ: 1530 nm – 1565 nm max. 360 channels (12,5 GHz Grid)
• L-Band λ: 1565 nm – 1625 nm max. 560 channels (12,5 GHz Grid)