Tech puts 'sneaky wave' wireless to the test

Philips, Texas Instruments and Samsung are among the other companies flexing their muscles as part of the IEEE 802.15 Working Group for WPAN, which is meeting this week in Dallas to settle on a new standard technology for wireless personal area networks, or WPANs.

Such networks create high-speed wireless connections over short distances to allow for synchronization between a personal digital assistant and a computer, say, or to connect a television to a cable TV box, and so on. The winning technology behind the standard, which will bear the name 802.15.3a, is expected to generate $1.39 billion in revenue by 2007, according to projections by Allied Business Intelligence.

The IEEE, or Institute of Electrical and Electronics Engineers, an industry body that often sets standards, isn't supposed to make a final decision on any of the 802.15.3a proposals until June, at the earliest. But already, there's been at least one clear winner to emerge from this week's meetings: a wireless technique developed by the military called ultra wideband (UWB). It's at the heart of 95 percent of the proposals that were submitted, according to Ben Manny, an Intel director of wireless technology development.

Supporters of UWB technology say it's a cheaper, less power-hungry way to wirelessly connect at short range than Bluetooth, the most popular WPAN technology now in use, which has been embraced by cell phone makers and creators of personal digital assistants, as well as by Microsoft and Apple Computer. UWB champions also say the technology is 100 times faster than Bluetooth, making it better fit for home-entertainment devices.

But UWB detractors say the commercially untested technology raises concerns about interference with bandwidth neighbors, which include some versions of Wi-Fi.

Once known as the "sneaky wave," UWB was developed by the U.S. military to communicate without being caught by then modern-day eavesdropping techniques.

It did so by being very, very wide. Most radio transmissions are assigned narrow bands of frequency in which to operate. For instance, cell phone broadcasts use about 100MHz at a time. But UWB's pulse is tens of thousands of megahertz wide and spills into bandwidth already occupied. But its inventors claim the wave has so little actual power, it doesn't cause any interference.

Some companies have submitted proposals that keep UWB true to its nature--a single very, very wide wave. But others have decided to break the wave into pieces that measure a few thousand megahertz each. Chipmaker XtremeSpectrum, for example, has submitted a proposal that assigns the wave to two different pieces of spectrum. Motorola, which once had two different proposals in the running, has since decided to back the XtremeSpectrum plan, a representative said Tuesday. Motorola is also licensing XtremeSpectrum's technology for use in its own products, the representative added. Other companies, such as Intel, propose assigning the wave to 14 different areas.

Both those types of UWB would operate at about the same speed--transmitting data at 100 megabits per second over a distance of 10 meters.

The difference is more of a market question. Some countries might have restricted a portion of the huge swath of bandwidth that America's FCC set aside for UWB last year. So the signal would need to find smaller quarters to operate in, said Manny, who's convinced the technology will be a part of the finalized 802.15.3a standard.

"I believe UWB will be in there, but there are a number of different ways to do it," Manny said.