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UWB: Background and
Emerging Applications
Ultra-Wideband (UWB) radio is
defined as any RF technology
utilizing a bandwidth of greater
than ¼ the center frequency or a
bandwidth greater than 500 MHz [1]
[2]. While UWB has been a known
technology since the end of the 19th
century, restrictions on transmission
to prevent interference with narrow-
band, continuous wave signals have
limited its applications to defense
and relatively few specially licensed
operators [1]. In 2002, the FCC
opened the 3.1 to 10.6 GHz band
for commercial applications of Ultra-
Wideband technology, and since
then UWB has become a focus
of academic study and industry
research for a promising variety of
emerging applications. To prevent
interference with neighboring
UWB has also proven viable as a
technology for new applications
in detection, positioning and
imaging. Modulation of UWB
signals using ultra-short pulses in
the order of nanoseconds enables
precise location and ranging at
the centimeter level [1] [6]. This
capability has useful potential for
military surveillance systems and
other high-accuracy location and
detection applications. The same
high-resolution, high-penetration
properties have also attracted
research in the medical field, and
a number of medical imaging
applications have shown successful
results. UWB systems have been
used for non-invasive, precise
detection of heart movements, and
high-fidelity imaging using safe, non-
ionizing radiation as an alternative
to more harmful X-ray imaging.[3]
Combining MMIC Reflectionless Filters to
Create Ultra-Wideband (UWB) Bandpass Filters
Brandon Kaplan, Mini-Circuits, Matt Morgan, National Radio Astronomy
Observatory, Tod Boyd, National Radio Astronomy Observatory
spectrum allocations like GPS at
1.6 GHz, the FCC has imposed
specific rules for indoor and outdoor
transmission of UWB signals, limiting
transmissions in the permitted
frequency range to power levels of
-41 dBm/MHz or less.
Research to date has explored many
potentially valuable applications for
UWB technology. For example, the
wide bandwidth of UWB provides
high channel capacity, allowing very
high-speed data transfer at very
low power. While the FCC power
mask limits the range of UWB
transmission to within roughly 10
meters, its high-speed, low-power
characteristics have made UWB an
attractive technology for certain
short-range M2M communication
applications like Wireless Personal
Area Networking (WPAN) as well as
low power sensor networks.[1]
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