Tuesday, April 20, 2010

Bell Labs' Phantom-mode DSL Achieves 300 Mbps at 400m

Alcatel-Lucent's Bell Labs unveiled a "DSL Phantom Mode" technique that achieves downstream transmission speeds of
300 Mbps over distances up to 400 meters and up to 100 Mbps at 1km. This new DSL performance boost is expected to reinvigorate copper access network, including in-building VDSL2 network, for 100+ Mbps services.


The gains are achieved using a virtual or "phantom" channel that supplements the two physical wires that are the standard configuration for copper transmission lines. This analogue phantom mode technique is further enhanced using vectoring to eliminate interference or "crosstalk" between copper wires, and the bonding of two copper pairs into an aggregated pipe. The company has demonstrated these techniques in lab tests.


The "phantom mode" technique of creating virtual channels has actually been understood for decades. Alcatel-Lucent said this breakthrough was enable by combining phantom mode with the power of fast processor to eliminate crosstalk between copper pairs in a binder. Practical implementation will require CPE capable of bonding the 3 channels over two copper pairs. Vectorized VDSL2 silicon will also be required.


"Beyond a showcase of the innovative technology for which Bell Labs is known, DSL Phantom Mode is a demonstration of Bell Labs' direct impact on the market and its ability to invent technology that serves as a competitive differentiator for Alcatel-Lucent and for its customers," said Gee Rittenhouse, vice-president of research at Bell Labs. "Similar breakthroughs in optical access technologies such as ten gigabit PON technology, for which
we recently won an FTTH Council Innovation Award, further show Bell Labs' continual and significant influence on Alcatel-Lucent's technology and portfolio leadership."http://www.alcatel-lucent.comhttp://