Bell Labs scientists are saying they have hit data transmission speeds of up to 10 gigabits per second over traditional copper telephone lines, a development that could result in service providers bringing gigabit speed to broadband networks without the high cost of having to replace copper wires with fiber inside the buildings.
In an announcement July 9, researchers at Bell Labs—the research unit of Alcatel-Lucent—said they were able to leverage the copper wiring and a prototype technology called XG-FAST to achieve 1 G-bps speeds over 70 meters on a single copper pair of lines provided by a European operator and 10G bps over 30 meters using two pairs of lines, a method called "bonding."
For network operators, the results could mean the ability to bring high-speed broadband services to businesses and homes in a more economical fashion. Data transmission tends to be faster over fiber, particularly over longer distances, so carriers are moving to fiber in their networks. They can relatively easily bring fiber to the home or business building, but installing new fiber cables in the building itself can carry a huge expense, or simply be too expensive or intrusive to do.
The Bell Labs' tests open up the possibility of bringing fiber up to or very close to the building, then leveraging the copper wiring already in the buildings to carry the data the rest of the way. Marcus Weldon, president of Bell Labs, said the testing is another example of the unit's efforts to come up with technological breakthroughs that are 10 times better than what is currently possible.
"By pushing broadband technology to its limits, operators can determine how they could deliver gigabit services over their existing networks, ensuring the availability of ultra-broadband access as widely and as economically as possible," Weldon said in a statement.
A range of factors affect broadband speeds over copper cables beyond distance, according to Bell Labs researchers. Frequency is one—the wider the frequency range, the faster the broadband speed. That said, there are diminishing returns in speed as the frequency range increases, they said.
Bell Labs' XG-FAST is an extension of the G.fast broadband standard being finalized by the International Telecommunication Union and will be commercially available in 2015. When that happens, it will use a frequency range of 106MHz to offer broadband speeds of up to 500M bps over 100 meters. XG-FAST uses an increased frequency range of up to 500MHz, which results in higher speeds over shorter distances, researchers said.
Federico Guillén, president of Alcatel-Lucent's Fixed Networks business, said XG-FAST will enable operators to accelerate deployments of fiber-to-the-home (FTTH) deployments by "taking fiber very close to customers without the major expense and delays associated with entering every home. By making 1G-bit symmetrical services over copper a real possibility, Bell Labs is offering the telecommunications industry a new way to ensure no customer is left behind when it comes to ultra-broadband access."
The test results are part of a larger plan by Weldon, who's been president at Bell Labs since November 2013, to return the institution to its original dual-prong mission: solve real-world problems while remaining alert to possible scientific discoveries that might come out of that work. Bell Labs' history can be traced back to the 1880s, and over the decades, researchers there helped develop such fundamental technology breakthroughs as the transistor, laser, Unix operating system, the C and C++ programming languages and radio astronomy.
Weldon told eWEEK in May that in the 1980s and 1990s, Bell Labs became more of an academic research facility that was doing great science but not addressing real-world problems. Weldon said he wants the institution to not only do the great science, but also to address challenges facing the communications industry.