DOT cautious about ultra-wideband
- By Paula Shaki Trimble
- Sep 19, 2000
The Transportation Department supports ultra-wideband, an emerging technology
for communications and positioning, but last week cautioned that more testing
is needed to ensure that UWB poses no threat to existing transportation safety
DOT submitted its position Sept. 12 on proposed rule-making by the Federal
Communications Commission to allow UWB products to operate without individual
licenses. FCC already permits the operation of some UWB devices on an experimental
UWB devices can facilitate X-ray-like imaging, wireless communications
and positioning and location. But DOT is concerned that UWB emissions may
interfere with the government's Global Positioning System, which is used
to provide aviation, maritime and military users with precise location and
timing information via radio frequency signals from satellites.
The DOT filing to FCC said:
* UWB is a promising technology that may offer significant public and
* Existing technologies and their users must continue to be protected
from interference, particularly those involved with safety-of-life functions
such as GPS.
* Carefully structured testing programs should determine the nature
and extent of protection from UWB emissions, if any is necessary.
"Billions of dollars of public and private funds have been spent [on
GPS and other communications, navigation and surveillance systems], and
future applications indicate that more will follow. This has not been and
should not be jeopardized by interference from other sources," the DOT filing
by general counsel Rosalind Knapp said.
Preliminary results of testing by DOT and the National Telecommunications
and Information Administration, which manages spectrum for government systems,
found that UWB emissions can interfere with GPS receivers or may be benign,
depending on the UWB parameters and on the application.
DOT also acknowledged that UWB has the potential to improve transportation
safety. For instance, ground-penetrating UWB radar could be used to examine
the condition of roadways and bridge decks, the filing said.
UWB devices may also provide a way to communicate between vehicles and
help with collision avoidance.