NEC transmits at 10.9 Tbit/s over DWDMTokyo 22 March 2001 NEC has set a new Dense Wavelength Division Multiplexing (DWDM) transmission capacity world record. NEC has successfully transmitted 10.9 Tbit/s (273 channels, each with 40 Gbit/s data speed) of information over 117km.
This unprecedented ultra-high capacity was achieved with three breakthrough technologies developed by NEC: the exclusive S-band amplification technology allowing light amplification in the 1490nm wavelength region; optimized system design technology for the ultimate 3-band (the S-band plus the conventional C- and L-bands) transmission;and ultra-dense channel multiplexing technology employing polarization multiplexing/demultiplexing technique.
This record-setting capacity will allow simultaneous long-distance transmission of more than 1 million high-speed ADSL channels over a single line of fiber, opening the new era of broadband networking applications.
NEC presented the details of this achievement on March 22, at the Optical Fiber Communication Conference (OFC 2001) post-deadline session, held in Anaheim, CA.
Recent advances in the Internet technology have resulted in the massive growth of data traffic demand all over the world. To cope with this traffic demand, WDM technologies have been introduced to cost-effectively upgrade the capacity of already-installed fiber facilities by sending information on different wavelengths (colors) of light. Until now, the long-distance WDM transmission system mainly employed two wavelength bands (wavelength groups): the C-band in the 1550nm wavelength region, and the L-band in the 1580nm wavelength region. By utilizing these two wavelength bands simultaneously, several under-10Tbit/s transmission results have already been reported, one of which was 6.4Tbit/s capacity demonstrated by NEC. However, to further increase the transmission capacity up to 10Tbit/s and beyond, the capability of the two wavelength bands had not been sufficient.
To solve this difficulty, NEC has been undertaking in an intense research and development effort, developing optical amplifiers that operate in the 1490nm wavelength region. The 1490nm wavelength region, called the S-band, is characterized by low signal attenuation next to the C- and the L-bands. With NEC's leading-edge technologies, the world's first S-band amplifier has been developed enabling triple-band transmission on a single line of fiber. This unique S-band amplification technology, together with optimized 3-band transmission system design technology, and polarization multiplexing/ demultiplexing technology, enabled simultaneous transmission of 273 channels each with 40Gbit/s data speed, for the total throughput of 10.9Tbit/s, nearly double the capacity of the previous 6.4Tbit/s record set by NEC.
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