10.22.2009 12:00 PM
Virginia Town Exemplifies White Space Usage
CLAUDVILLE, VA.: The
community of Claudville, Va., is quintessentially “unserved,” an archetype for
using TV spectrum for wireless broadband. The town of 900 people sits on the
rugged and forested edge of the Blue Ridge, in the sparsely populated territory
of Southwestern Virginia. In surrounding Patrick County, pictured left, there are an average of 20
houses per square mile. Per capital income is $15,574.
Internet access is limited, and up until a couple of years ago, it was entirely
“We have been working for many years to help the people of Claudville get
high-speed data services that urban areas take for granted,” said Roger Hayden,
director of Claudville Computer Center and the Patrick County Broadband Task
Hayden and his colleagues realized success. Claudville hit the headlines this
week when Rep. Rick Boucher (D-Va.) announced the launch of an experimental
white-space broadband network in the community.
The Claudville experiment represents the first use of unoccupied TV channels
for full-time, non-broadcast communications. The local high school, a cafe, a
fish hatchery and a community center were outfitted with computers to take
advantage of the area’s first real broadband access. TDF Foundation, a
Washington, D.C. venture cap-fund, helped build the facilities. Spectrum
Bridge, a private company in Lake Mary, Fla., designed the network and is in
charge of monitoring it for interference.
White spaces, once known as “taboo” TV channels, are the most hotly
sought-after properties in all of radio frequency spectrum. Demand for spectrum
intensified with the explosion of cell-phone use. And now that TV is
all-digital, the taboo channels once left open to prevent signal interference are
considered fair game.
Microsoft and Dell were two of the first and most powerful advocates for using
white spaces for broadband communications. Both supplied technology for the
Claudville network, which was launched on a single frequency under an 18-month
experimental license from the FCC.
Both computer giants, along with Google, pushed to launch devices in the unused
TV channels without having to license them with the FCC. The commission agreed
to the arrangement--marking the first time an entity has been granted the
unlicensed use of U.S. radio frequency spectrum. Those devices are still in the
prototype stage. Indeed, Microsoft was recently granted an experimental license
to test its prototypes in the Redmond, Wash. area. (See “FCC Grants Microsoft White Space Licenses”)
In Claudville, connectivity is supplied through WiFi access points. The white
space frequency is used for backhaul only, so the network is not yet ready for
The primary concern of broadcasters is signal interference. Broadcast
engineers, including Charles Rhodes, who ran the technical arm of the Advanced
Television Testing Lab, noted that digital TV signals required a buffer zone (à
la taboo channels) as much as did analog signals. Digital reception was--and
still is--being worked out.
The TV stations serving Claudville are all miles away. WDBJ-TV, the CBS
affiliate, and WSLS-TV, the NBC, are out of Roanoke, Va., 54 miles north-northeast. WXII-TV, another NBC, and WGHP-TV, a Fox, are out of Winston-Salem,
N.C. 35 miles south.
Peter Stanforth, chief technology officer of Spectrum Bridge, said no
interference has yet been identified.
If it is, it will be relatively easy to trace because of the fixed operations
of the network. Interference from mobile devices will be much more difficult to
pint down, but they’re supposed to sniff out spectrum occupied by TV channels
and jump to unused ones. The Claudville system relies on a database compiled by
Spectrum Bridge from FCC licensing information.
Dave Donovan, chief of the Association of Maximum Service Television, said it’s
crucial for that information to be correct.
“We’ve always said we support using spectrum in rural areas to be used for
broadband, but it requires an accurate database,” he said. “Our biggest concern
there was that the spectrum they’re using does not interfere with over-the-air
Over-the-air television is considered by some to be a waste of spectrum. Nearly
80 percent of TV households in the county opt to pay for piped-in programming.
Wireless broadband seems a better use for the TV spectrum, particularly in
communities like Claudville.
“Our students and teachers did not have access to computers or broadband
connectivity until now,” said Jerry Whitlow, administrator of Trinity Christian
On Capitol Hill, Boucher thanked everyone involved with launching the
Claudville system, including a Republican and a Democratic FCC commissioner.
The tiny town represents an inroad into the TV spectrum, as well as a
President Barack Obama charged FCC Chairman Julius Genachowski to make
nationwide broadband access his singular goal. Genachowski and the FCC today established rules
to keep Internet service providers from controlling traffic on the Web, under
what’s known as “network neutrality.” His deputy, Blair Levin, is reported to
be pitching broadcasters on giving up their spectrum for a split of auction
fees, though such a scheme would have to make it past the likes of Sen. John
McCain (R-Ariz.) widely considered a long-time and vociferous detractor of the broadcast
Meanwhile, students in Claudville’s Trinity High School are surfing the Web on
-- Deborah D. McAdams
(Image by Jimmy