Emerging Technology;|;DOI: 10.1145/1839676.1839704
Wide open spaces
The U.S. Federal Communications Commission’s decision to open
frequencies in the broadcast spectrum could enable broadband
networks in rural areas, permit smart electric grids, and more.
NeWLy aVaILaBLe FrequeNCIeS in the broadcast spectrum should increase Internet ac- cess and spur innovation, U.S. Federal Communications Commission (FCC) Chairman
Julius Genachowski said in opening
those frequencies to unlicensed commercial use.
When TV broadcasters switched to
narrower digital channels in 2009, they
freed up frequencies below 700 megahertz, the so-called “white spaces” between channels. Signals at these frequencies can travel about three times
as far as the traditional Wi-Fi frequency
of 2. 4 gigahertz, and easily penetrate
buildings and other physical obstacles.
The new FCC rules create room for
two classes of devices: fixed, high-power ones that transmit at up to 4 watts
and portable, low-power devices limited to 100 milliwatts. Harold Feld, legal
director of Public Knowledge, a Washington, D.C., public interest group,
says thousands of small wireless Internet service providers in rural areas, un-derserved by broadband connections,
will be quick to take advantage of the
range and penetration, to achieve good
coverage with fewer towers.
But that will not happen tomorrow.
“It’s going to take a minimum of 18
months to get even the most basic devices approved and out there,” Feld says.
pHotograpH By J.D. LasIca/ socIaLmeDIa.BIZ
Neeraj Srivastava, vice president
of marketing at Spectrum Bridge, a
wireless networking company in Lake
Mary, FL, that works with white spaces,
expects the first enhanced Wi-Fi systems, using fixed devices, could start
appearing in the first quarter of 2011.
Under experimental licenses from the
FCC, Srivastava says Spectrum Bridge
has run several pilot programs that
demonstrate the near-term uses.
One project provided the connectivity to deploy smart grid power monitors
across the electrical system in Plym-
u.s. federal communications commission chairman Julius Genachowski.
outh, CA. By placing white-space radios
at substations, Spectrum Bridge created a wireless network to keep track
of power usage and simultaneously
supplied the town’s residents with
wireless broadband. A project in Wilmington, NC, provided wireless links to
inaccessible water-quality monitors
and traffic-monitoring bridge cameras. At a hospital in Logan, OH, where
concrete walls blocked Wi-Fi and the
building’s structure made cabling difficult, Spectrum Bridge created a wireless network to monitor patients, share
data, and access security cameras. They
also brought broadband access to rural
The 4-watt applications can use ex-
isting standards; Spectrum Bridge used
a modified WiMAX radio in the Logan
hospital, for example. Meanwhile, IEEE
is working on a standard for the low-
power devices, comparable to its 802.11
standard for Wi-Fi. That will determine
the design of chips for the smartphones
and laptops that will use them, Srivas-
tava says, so it may be more than two
years before the appearance of the first
neil Savage is science and technology writer based in
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