The Bush administration is on record this week in support of the adoption of current Federal Communications Commission (FCC) ultra wideband (UWB) emission limits for all outdoor device applications.

In an ongoing, lengthy proceeding at the FCC, military, aviation, fire, police and rescue officials have voiced concerns that interference from wireless UWB devices could potentially disrupt critical public services and crucial military operations.

Unlike conventional wireless radio systems that operate within a relatively narrow bandwidth (i.e., Bluetooth, IEEE 802.11b, IEEE 802.11a) UWB operates across a wide range of frequency spectrum by transmitting a series of very narrow and low power pulses. The UWB industry says this combination of broader spectrum, lower power and pulsed data means that ultra wideband causes less interference than conventional narrowband radio solutions.

In February 2002, the FCC authorized the commercial, unlicensed deployment of UWB. A year later, the FCC amended the rules to facilitate the operation of through-wall imaging systems by law enforcement, emergency rescue and firefighter personnel in emergency situations.

The FCC also eliminated the requirement that ground penetrating radar (GPRs) and wall imaging systems operate with their 10 degree dB bandwidths below 960 MHz or above 3.1 GHz and specified the limitations on who may operate GPR systems and wall imaging systems and for what purposes.

Late last week, the National Telecommunications and Information Administration (NTIA), the executive branch's primary policy voice on telecommunications and information technology issues, said it believes the restrictions on the pulse repetition frequency used by UWB are unnecessary as long as the current emission limits for handheld devices are met.

"We support the FCC's clarification of the UWB rules so that this new industry sector can take hold and grow while we protect critical federal systems from harmful interference," Michael D. Gallagher, acting head of the NTIA, said in a statement. "The rules adopted by the Commission in its first Report and Order successfully strike that balance, and provide a stable platform for development of new devices that will save lives, boost U.S. productivity and enrich the experience of U.S. consumers."

NTIA's filing also includes analysis of pulsed "frequency hopping" vehicular radar systems operating in the 22-29 GHz frequency range, with the NTIA finding no greater interference to government passive sensing satellites than is presently permitted for impulse UWB vehicular radar systems.

The NTIA noted, however, that its conclusions do not apply to UWB "frequency hopping" systems in other bands. In its comments, NTIA proposes a compliance measurement procedure for pulsed frequency hopping vehicular radar systems.

One FCC proposal that the NTIA filing does not support is the elimination of the minimum bandwidth requirement from the definition of a UWB transmitter. According to the NTIA comments, removing the minimum bandwidth requirement could allow unlicensed non-UWB operations in restricted bands.

The FCC had been attempting since 1998 to a find a way to approve and promote UWB technology because of the potential commercial and public safety applications.