Major carriers, arguing that their networks are clogged with smart-phone and tablet traffic, are increasingly implementing data throttling, the practice of targeting heavy users by slowing down data-transfer speeds. Now a gadget invented at Bell Labs—a programmable, pint-sized transmitter that requires no new traditional cell towers—could rapidly add capacity and thus help avoid data bottlenecks.
The gadgets are known as light radio cubes. Measuring just six centimeters on each side, they are miniature transmitters and receivers that can be programmed to work flexibly in different contexts to add capacity.
Two devices together can serve a compact area such as a stadium or train station—handling just as much traffic, in that compact area, as a whole cell tower can serve a wider area. A cluster of 10 to 20 of them can form an array that replaces the transmitters atop a typical cell tower. They can boost capacity in part by collectively reshaping the radio beam in real-time toward the incoming signals to optimize performance.
The demands on mobile networks are expected to explode over the next four years. Bell Labs has estimated that traffic will grow by a factor of 25, while Cisco says it will grow 18-fold by 2016. Either way, the system will have to be remade to accommodate the traffic.
“I think we are really at the cusp of a major transformation of what a wireless network is and does, and its value to everybody,” says Mike Schabel, a vice president at Alcatel-Lucent, which is commercializing the technology.
Light radio cubes could add efficiencies in other ways, too. In a traditional cell tower, as much as 50 percent of power is lost just in moving a signal from the amplifiers and other components in a base station up to the transmitter at the top of the mast. But in the cubes, these components are miniaturized and distributed onboard each unit, reducing losses. Overall, Schabel says, the units can reduce costs by 40 percent compared to adding network capacity via more macro cells.
But first, real-world tests must be completed. So far, the technology—which can work with 2G, 3G, and 4G networks—is being put through trials by Telefonica, the Spanish carrier, Etisalat, in the United Arab Emirates, and China Mobile, which has 650 million subscribers.
Alcatel-Lucent is hardly the only player working on the concept; other companies, including Ericsson, Huawei, Cisco, Samsung, NEC, and Nokia-Siemens, are also developing versions of the technology, known generally as small cells. A market research firm, Visiongain, predicts that more than one-third of the world’s mobile network operators may deploy small cells this year.