In February 2002, the U.S. Federal Communications Commission (FCC)
authorized limited commercial use of UWB wireless communication devices. The
types of operation that are currently approved are listed in Figure
. Approval in
Europe and Asia is expected soon.
The U.S. FCC is currently working on setting emissions limits that would
allow UWB communication systems to be deployed on an unlicensed basis,
following the rules for radiated emissions of intentional radiators
. These
are the same rules that govern the radiated emissions from home computers. This
rule change would allow UWB-enabled devices to overlay existing narrowband
systems, which is currently not allowed. This could result in a much more
efficient use of the available spectrum. Devices would be able to fill in the
unused portions of the frequency spectrum in any particular location.
Taking a conservative approach, the U.S. FCC chose to restrict UWB radio
spectrum use from 3.1 to 10.6 GHz. This applies to UWB communications
applications with full incidental radiation power. The U.S. FCC hopes that this
is far enough away from the 1.6-GHz band that is used for GPS communication.
Outside the 3.1 to 10.6 GHz band, signals must be attenuated by 12 decibels
(dB), with 34 dB of attenuation required in areas near the GPS-frequency bands.
More liberal restrictions were created for law-enforcement and public
safety personnel using UWB units to search for earthquake victims or other
missing people.