Verizon trials 200G long-distance transmission using 16-QAM
Created September 13, 2013US carrier Verizon has demonstrated 200Gbps optical transmission over 260 miles of its optical network linking New York and Boston.
The trial used equipment from system vendor Ciena that included the vendor’s WaveLogic3 coherent optical processor and test software to implement higher order modulation based on 16-QAM (quadrature amplitude modulation). The 16-QAM signal was carried over a single wavelength and occupied a 50GHz channel. The trial was conducted for over a month with the 200G traffic being sent alongside live customer traffic.
“Proving greater spectral efficiency and a lower cost per bit, this trial illustrates the ability to double the traffic carrying capacity of optical channels with no change to the underlying infrastructure,” said Francois Locoh-Donou, senior vice president, global products group at Ciena.
Verizon reported in late 2012 that it had already deployed 100Gbps wavelengths in over 13,000 miles in the United States and 1,616 miles in Europe. The operator said increased video traffic, growth in data traffic from its LTE rollout, and cloud usage are driving increased capacity.
The 16-QAM higher modulation scheme offers a way to double capacity but at the expense of reach. Operators see the technology as a valuable way to extend capacity for links in shorter distance metro and metro/ regional networks.
In February, Orange (France Telecom) announced that it had deployed the world’s first 400 Gbps per wavelength connection. The link between Paris and Lyon, a relatively short distance, used Alcatel-Lucent’s coherent processor and also used higher order modulation.
By Roy Rubenstein
See Also:
Press release: Verizon successfully completes 200G field trial
Gazettabyte: Ciena: Changing bandwidth on the fly
