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A super-channel is an evolution in Dense Wavelength Division Multiplexing (DWDM) in which multiple, coherent optical carriers are combined to create a unified channel of a higher data rate, and which is brought into service in a single operational cycle. ==Background== From around the year 2010, coherent optical transmission at 40Gbit/s and 100Gbit/s began to be deployed in long haul optical networks around the world. Coherent technology enables higher data rates to be sent over long haul (typically >2,000 km) optical transmission networks, compared to the historical modulation and detection technique, Intensity Modulation with Direct Detection (sometimes referred to as Non-Return to Zero, NRZ or On/Off Keying, OOK), which had been widely used for several decades. However, a coherent detector requires that the incoming phase modulation information is digitized before being sent to a high performance digital signal processor (DSP). Within the DSP, optical impairments such as chromatic dispersion and polarization mode dispersion can be compensated for. Digitizing the received signal requires an extremely high speed analog-to-digital converter (ADC) capability. Current commercially deployed coherent products are limited to 200 Gbit/s per optical carrier. Going beyond 200 Gbit/s per WDM channel requires the use of multiple carriers to make up a single WDM interface. The resulting multiplex, called a super-channel (or superchannel), creates a multi-wavelength signal in which each wavelength will operate at the maximum data rate permitted by commercially available ADC components. The primary advantages of a super-channel approach are increased spectral efficiency (a consequence of both coherent detection and the possibility of tight spectral packing of the subcarriers making up a super-channel), and operational scalability (the ability to bring larger units of long haul optical capacity into service for a given operational effort). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Super-channel」の詳細全文を読む スポンサード リンク
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