120-Wavelength Optical Transmission System
Emerging service networks, such as cloud computing, VR, and ultra-HD video, continuously drive increasing service traffic, imposing higher requirements on the transmission rate and performance of transmission networks.
The single-wavelength rate and performance improvement demand more fiber spectrum resources. Due to slow fiber deployment, the most effective way to cope with the ever increasing network traffic is to improve the single-fiber capacity by expanding the fiber spectrum.
What Is Super C Band
Super C band uses the ultra-wide C band (C120) in addition to the traditional C band (C80) and the extended C band (C96). It increases the available wavelength range.
Super C band can transmit 120 wavelengths at a 50 GHz channel spacing and transmit 80 wavelengths at a 75 GHz channel spacing, greatly expanding the effective working spectrum compared with the traditional C band and extended C band. Therefore, it is called Super C band.
Performance
Improving the system transmission capacity
When the transmission rate is the same and the channel spacing is 50 GHz, the Super C band supports a maximum of 120 wavelengths, while the traditional C band supports a maximum of 80 wavelengths. The Super C band increases the transmission capacity by 50%.
Improving the system transmission distance
When the transmission rate is the same and 80 wavelengths are used for WDM transmission, the channel spacing for Super C band is larger. The line-side optical module can use the line modulation formats with stronger transmission capability, doubling the transmission distance.
Example: When the transmission rate is 200 Gbit/s, in the traditional C band, 200G 16QAM transmission is used, and the maximum transmission is 1000 km; with Super C band, the 200G QPSK transmission can be used, and up to 2000 km ultra-long haul transmission is supported.
Optical-layer components of Super C band support the wavelengths of traditional C band/extended C band.
Super C band can evolve to Super C+L band. In the initial phase, the network is configured with WDAPXF, and smooth upgrade to the L band is supported without changing the main optical path fiber.
