Researchers overcome barrier to
shrinking wireless devices
ARBOR, Mich.---James Bond-style technologies such as
cell phones the size of earpieces and invisible sensors
sprinkled about to detect toxins are closer to reality.
University of Michigan researchers have figured out
how to build wireless systems even smaller while still
retaining range and power efficiency.
One obstacle to further shrink small wireless devices
has been trying to fit all the components onto one chip
but U-M researchers have built a tiny silicon-compatible
antenna and frequency resonator that will do just that.
The antenna and resonator are two of the most problematic
off-chip components in wireless systems. The two components
require large amounts of space off the chip---think
of a cell phone antenna extending outward---thus limiting
how small a device can be built.
Until now, small antennas weren't power efficient and
resonators were not accurate, said Kamal Sarabandi,
director of the radiation laboratory department in electrical
engineering and computer science (EECS). His research
group developed the antenna.
The technology is being developed for use in environmental
sensors, but could be applied to cell phones, laptops
and other wireless devices, said Michael Flynn, head
of the wireless interface group.
"We could have cell phones almost the size of an
earpiece," Flynn said. "You could have sensor
nodes that are almost invisible, you could just sprinkle
Rather than using a traditional wire antenna, researchers
built a slot antenna. In a slot antenna, instead of
the metal wire, imagine covering an entire plane with
metal, leaving only a slot or groove in the metal bare.
Wire surrounds the groove so it's much more effective
at radiating electromagnetic waves in a small antenna,
Sarabandi said. Because of the antenna's shape, the
wireless system does not need a network to match the
antenna's frequency to the rest of the electronic device.
Sarabandi's group has been talking with Intel about
a possible collaboration. Intel is interested in using
the technology in laptop computers, Sarabandi said.
The second component U-M scientists replaced is the
quartz frequency resonator, which allows a wireless
device to focus on a specific signal and ignore others.
The work was done by EECS associate professor Clark
Instead of quartz, U-M scientists used MEMS-based technology
to build the resonator so it can be fitted onto the
chip. It functions similarly to how the rim of a wine
glass thrums when flicked by a finger. The wine-glass
rim design helps retain the purity of the signal.
For more information on the WIMS center, visit: http://www.wimserc.org/
For Sarabandi, Flynn, and Nguyen, visit:
story has been adapted from a news release -
Diese Meldung basiert auf einer Pressemitteilung -
tekst is gebaseerd op een nieuwsbericht -