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Companies Try to Create Room on Radio Spectrum

John C. Coleman, left, and Scott Garlington of xG Technology, which is developing ways of sharing the radio spectrum.Credit...John Van Beekum for The New York Times

Cellphone carriers like AT&T and Verizon say they are worried about running out of the radio spectrum that carries wireless calls and data, and they want the government to give them more chunks of it. But a number of companies are developing technology that could change the whole spectrum game by using radio frequencies more efficiently.

Their efforts are getting a powerful endorsement. A presidential advisory committee, which includes executives from Google and Microsoft, plans to present a report this month that explores ways in which computerized radio technologies could make better use of spectrum.

In a presentation last month, the committee said the technologies would allow federal agencies and other organizations to share the spectrum bands they control with the carriers, and could potentially improve efficiency by a factor of 40,000.

One technology addressed by the report is called cognitive radio, in which cellphones scan for available frequencies and choose the best one to use. For example, if the government has reserved some spectrum for use at an Air Force bombing range, but no bombing is happening on a particular day, cognitive radio could allow a phone to sense the open channel and switch to it.

A Florida-based company, xG Technology, developed a version of cognitive radio for the Army that allows communication on military bases. Its technology scans for open channels and clears up interference on busy channels so more people can use them.

Rick Rotondo, vice president for marketing at xG, compared its technology to noise-canceling headphones, which listen for noise and generate a signal to cancel it out. In a similar way, xG’s cognitive radio technology listens for interference and calculates a way to reduce it, he said.

Cellphone carriers have been warning the government about a looming “spectrum crisis” — a situation in which the rising demand for wireless data will eventually exhaust their resources. This, they say, could slow mobile devices and stifle the economy. But the report suggests that spectrum constraints could be resolved if the government were to push carriers to embrace technologies that provide greater efficiency.

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An xG Technology demonstration vehicle. The company can provide access to the Internet even from remote locations.Credit...John Van Beekum for The New York Times

John C. Coleman, chief executive of xG Technology, said concerns over spectrum capacity were valid, because the techniques that the carriers are now using will lead to a shortage. But newer technologies, he said, would fix the problem.

“The spectrum crisis is completely avoidable,” Mr. Coleman said. “If we start incorporating advanced and proven technologies like cognitive radios and smart antenna systems now, we can get ahead of the mobile broadband demand curve and stay ahead of it.” 

Other companies in this industry include Shared Spectrum, which has also developed cognitive radio systems for the Defense Department, and Cognitive Radio Technologies, which is working to commercialize technology developed at Virginia Tech.

Some veterans of the wireless industry, like Martin Cooper, a former Motorola executive who helped create the first cellphone, have been saying all along that technology could be the answer to the wireless industry’s growing pains.

“The committee is proposing the approach that I’ve been advocating for over 20 years,” he said. “The magic that makes all of this work is already known.”

Mr. Cooper said that even if the government granted the carriers a little bit more spectrum, there would be no guarantee that it would be enough to handle the ever-rising number of data-guzzling smartphones and tablets.

“How can 20 percent more spectrum — which is, in their wildest dreams, as much as they’re ever going to get — how can that solve the problem when you need 20 times more spectrum?” he said. “They’re not using technology that exists today and was demonstrated 10 years ago.”

The major carriers have seemed wary of any technology that might reshape the status quo in their business. CTIA, the wireless association that represents the carriers, has said that its members are excited about the idea of spectrum sharing, but that giving the carriers more spectrum should still remain the government’s top priority.

Chris Guttman-McCabe, vice president for regulatory affairs at CTIA, said he was skeptical about cognitive radio technology in general because it had not yet been used commercially and it was unclear whether the technology would be a viable solution nationwide.

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Wireless companies say that smartphones are threatening to overwhelm their networks, and are asking the government for help. But some experts maintain that technology already has the answers.

The association says that even if the technologies described in the report can indeed improve spectrum capacity a thousand times, it wants the government to make more spectrum available by “clearing” frequencies that are currently underused.

But if the technologies succeed in delivering so much extra capacity, why would carriers need more spectrum? Mr. Guttman-McCabe said that it was not clear who would get access to the spectrum that would be shared with federal agencies, and how often the carriers would get to use it. He said it would still be preferable for the wireless industry to have more spectrum for itself.

“We’re eager to see that the administration is going to focus on clearing spectrum and that the fallback will be sharing — that the gold standard is trying to find cleared spectrum,” Mr. Guttman-McCabe said.

Even if President Obama chose to adopt newer technologies for spectrum sharing, it would take some time to roll out all of the technology required to get a big increase in efficiency. For example, for cognitive radio to work in the mass market, smartphones would need to ship with more advanced antennas and circuitry so they could scan for clearer channels, Mr. Rotondo said.

Cognitive radio is one of several technologies that could help make better use of radio spectrum. Mr. Cooper said he had more faith in nearer-term solutions, like smart antennas. A conventional radio antenna on a cellphone tower spews energy out in all directions. By contrast, a smart antenna would direct energy straight at the phones, reducing congestion. (Mr. Cooper previously founded ArrayComm, a company that made software for smart antennas, but he is no longer associated with it.)

One approach that is being tested on cell networks is femtocells, which are also called small cells. Some femtocells, which consumers can buy to install in their homes, are designed to improve cellphone reception by routing calls and data over broadband connections.

Julius Genachowski, chairman of the Federal Communications Commission, said at a CTIA Wireless conference last month that small cells would be critical to meeting the rising demand for mobile data because they allowed carriers to build a denser patchwork of cells.

“Small cells are a big deal,” he said during a keynote session. “The small-cell revolution will drive enormous change in wireless in the coming years.”

The commission will be holding proceedings on making a band of spectrum available for carriers to install small cells on their networks, reducing the pressure on the carriers’ main spectrum bands.

A version of this article appears in print on  , Section B, Page 1 of the New York edition with the headline: Sharing the Air. Order Reprints | Today’s Paper | Subscribe

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