3.65Tbit/s (365x10Gbit/s) over 6,850 km on a single fiber-a distance comparable to most transatlantic cable links
Paris, November 29, 2001 - Alcatel (Paris: CGEP.PA and NYSE: ALA), world leader in intelligent optical networking, has achieved another world record in optical submarine optical transmission by transporting 3.65Tbit/s capacity (365x10Gbit/s) over 6,850km on a single fiber. The unprecedented number of 365 wavelengths, each operating at 10Gbit/s over a distance equivalent to most transatlantic cable links, reinforces Alcatel's leadership in submarine optical technology.
This breakthrough would allow the simultaneous transmission over a single optical fiber and across the Atlantic Ocean, of 45 million voice calls, or 552 CD-Roms, or 35 Encyclopedia Britannicas, or 16 high definition movies. It will enable operators and service providers to dramatically increase the capacity transported over a single fiber, thereby further optimizing the cost of their networks.
The laboratory demonstration was achieved using wide bandwidth optical amplifiers and an advanced fiber map-an innovative assembly of fibers which optimizes transmission quality over all wavelengths. The particular combination of fibers used allowed Alcatel researchers to squeeze wavelengths to a spacing of 22.2GHz between channels, less than half the International Standard of 50GHz, hence allowing the unprecedented number of 365 wavelengths. Consequently, this gave a spectral efficiency (which measures how effectively one is using the bandwidth) of 0.45 bits/Hz-substantially better than today's value of 0.2 bits/Hz. The remarkable combination of the high spectral efficiency with a large optical bandwidth of 66nm produced the high throughput achieved in this experiment.
This demonstration also significantly contributes to Alcatel's objective of producing simpler and cheaper global networks by improving the integration between terrestrial and submarine systems. Indeed, it was achieved with NRZ modulation format (Non Return to Zero) for the information modulation instead of the more complex modulation formats normally utilized for submarine transmissions. NRZ format is commonly used in terrestrial networks-therefore this laboratory result opens a bridge between the technology used for submarine applications and those utilized for terrestrial applications.
"This world record confirms Alcatel as a key innovator in submarine network technology. Alcatel's continuous breakthroughs in R&D allow the Company to prepare next-generation solutions in order to provide its customers with the highest performance and lowest cost," said Bernard Le Mouël, CTO of Alcatel's Optics Group. "Furthermore, due to its end-to-end optics R&D and its complete technology portfolio, Alcatel is the sole supplier able to offer seamless solutions for terrestrial and submarine infrastructures."
About Advanced Fiber Map
The "fiber map" is like an Underground map of the types of fiber used in the end-to-end link. The fiber type is changed periodically along the link so that on average all the wavelengths travel at the same speed, or experience the same dispersion. (Dispersion: the fact that different wavelengths travel at different speeds in materials such as glass or water, results in rainbows from water droplets or as light passes through a prism.) This is important for even a single channel contains a small spread of wavelengths and too much dispersion would result in pulses spreading out in time. Over 6000-7000 km the spreading could become so great that one pulse merges into the next. One cannot use fiber with no dispersion, for this creates interference between different channels; it occurs because with no dispersion the pulses in different wavelengths all travel together and get the maximum time to interact due to non-linear effects. Choosing a "fiber map" with different dispersive fibers avoids all the wavelengths from traveling together; the mixture (of positive and negative dispersions) results in close to zero average dispersion, which avoids too much individual pulse spreading.
About Alcatel
Alcatel is the only vendor to master all optical network elements, from optical components, optical fibers, DWDM systems and microwave radio links to core routers and network intelligence, and from terrestrial to submarine solutions. Alcatel is also the only company to provide both terrestrial and marine services for the installation and maintenance of global, seamless optical networks. According to RHK's 2000 study, Alcatel holds the number two position in global optical transport market with 20% market share, distancing itself from other competitors. RHK also reported that Alcatel reaffirms its number one position in submarine networks with 41% worldwide market share. Moreover, Alcatel claims to be the world leader in total terrestrial and submarine DWDM systems, in digital cross-connects, which contain the enabling technology for operators to offer high bandwidth services, in SDH networks and in microwave radio links. Alcatel's optics business comprises terrestrial and submarine transmission systems, fiber optics, optical components and microwave radio links. Alcatel has launched a new class of Alcatel stock which is intended to track the performance of Alcatel Optronics, the Company's optical component business.
Alcatel builds next generation networks, delivering integrated end-to-end voice and data networking solutions to established and new carriers, as well as enterprises and consumers worldwide. With sales of EURO 31 billion in 2000 and 110,000 employees, Alcatel operates in more than 130 countries. | |
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