One of UWB's defining characteristics is that it requires very little electrical power -- one source says it uses 0.001% as much power as a cell phone -- and thus is virtually undetectable by conventional radios, which see the UWB signal as just very quiet background noise. Thus, a UWB telephone would use so little power that it could remain on for weeks without needing to be recharged. And because it uses all available spectra, UWB may well be cheaper to design and manufacture than conventional radios that require careful tuning to a specific frequency.

A UWB transmitter and receiver must be closely coordinated and synchronized to send and receive pulses with an accuracy of trillionths of a second. The receiver responds only to a familiar pulse sequence. This makes UWB very secure, which explains why it was once used for clandestine communications by military and espionage agencies. UWB's broad frequency range includes the ultralow frequencies the U.S. Navy uses to communicate with submerged submarines.

UWB products will include radar and electronic location and positioning devices in addition to radios. UWB radar can see right through walls, ceilings and floors that would block or reflect other types of radio signals. As an electronic measuring technology, UWB is more accurate than Global Positioning System satellites, and it can be used indoors. The Navy reportedly plans to put UWB markers on almost everything it ships overseas, just to track materiel and keep it from being stolen.

Eventually, UWB networks are expected to run at speeds up to a gigabit per second and therefore should be able to handle all of the phone, television, and Internet traffic for a home or small business.

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