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Future Phones-Smarter Still

Wireless devices that morph through different “personalities” on the fly would be a boon to their users. But at the same time they create policy problems, as new technologies that cross boundaries often do. Historically, the FCC authorizes each piece of equipment for a type of use and specific channel. How should the regulators license mobile phones and base stations that can readily be changed after they’re in use? How free should third parties be to load new software into your phone? How will it be possible to distinguish legitimate upgrades of the network from rogues trying subvert it?

The FCC decided that rules to cover these scenarios were not needed-yet. But it also concluded it should facilitate this technology’s evolution. A main reason is the lack of enough spectrum for third-generation wireless services in the United States at present. So equipment that sniffs out and utilizes unused swaths of spectrum could alleviate what the FCC calls the U.S. spectrum “drought.”

To do this, however, will require both base stations and handsets to become supersmart-a leap to what Joe Mitola calls “cognitive radio.” A cognitive device will not only scan its spectral environment; it will also have built-in memory and maps and positioning capabilities. Those will enable it to react intelligently to its environment.

Over the past two years, Mitola built a crude civilian version of a cognitive radio as a doctoral project for Sweden’s Royal Institute of Technology. When this device is outdoors, it configures itself to use the prevailing cellular phone protocol; when carried indoors it switches to the format of the building’s local area network. Mitola explains that a more advanced version could “know” that the person carrying it is in trouble and send a distress signal on the local emergency frequency to give rescuers its location.

But mobile phones that reorient to a new channel for temporary use would have to get permission to “rent” that spectrum for some period of time from the official licensee. In a paper that foreshadowed his doctoral thesis, Mitola proposed a payment system that would employ the signal protocols. Using such a system, your intelligent handheld would scan the spectrum to find a channel that was not in use at the moment; for example, it might find one that the local fire department had the license to use but was offering for rent. Your radio would bid to rent the channel. The fire department’s radios, receiving the bid, could agree-or wait for other bids. But the instant the station’s bells rang and the firemen needed their channel back, their radios would bump the renter off. Mitola reckons the channel’s owner could regain control in 25 milliseconds-a delay that would be unnoticeable to human speakers. Your cognitive mobile phone would sign off, reckoning and paying a bill for time used, then start scanning for another open channel.

The FCC, in endorsing this vision, has joined forces with an unlikely ally: George Gilder, self-styled seer of the “telecosm” and critic of the FCC for holding back innovation. For years, Gilder has predicted that intelligence will grow at the edges of the wireless telecom network with the result that channels become fluid. Wireless devices and networks that employ flexible software, he says, will “transform the entire world of wireless communications,” the way personal computers transformed wired networks.

The swaths of spectrum that are most commercially desirable are often referred to as prime beachfront property. But Gilder wants people to stop thinking of spectrum as some kind of ethereal analogue to physical land. “Smart radios suggest not a beach but the endless waves of the ocean itself. You can no more lease electromagnetic waves than you can lease ocean waves.”

Making that ocean available to billions of people could be one impact of flexible software-based wireless networks. But even before we reach this nirvana of spectrum abundance, the technology could make wireless networks more cost effective and future-proof-and keep the wireless revolution rolling.

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Tagged: Communications

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