TV Airwaves Fill the Broadband Gaps
Companies are working to provide long-distance Internet services to rural areas via unused TV spectrum.
About five billion people lack access to high-speed Internet, with few options from traditional infrastructure.
Three years after the U.S. Federal Communications Commission approved using spare TV frequencies for long-range wireless Internet, the technology is finally poised for commercialization—filling broadband gaps in rural U.S. areas and in developing nations.
At least 40 experimental installations are up and running in the United States—including in a North Carolina county (see “Super Wi-Fi Blankets First County in U.S.”) and in East Houston, Texas—along with others in Singapore, Vietnam, and several African countries in programs involving Microsoft, Google, and local telecom companies.
And last week, West Virginia University became the first in the U.S. to install the technology, known as super Wi-Fi, which uses “white spaces,” or unused channels in the TV spectrum (see “Wireless Spectrum Deal Could Unleash Super Wi-Fi”).
The hardware and databases required to commercialize the technology are also now receiving the necessary FCC approvals for general sale without experimental licenses.
The hallmark of the technology is its ability to get a signal through buildings and over hills—just like TV signals. In West Virginia, two miles from the transmitter, dorm rooms are getting 12-megabits-per-second Internet—relatively slow speeds, but better than the earlier dialup service.
Sending and receiving signals over unused TV spectrum is tricky to engineer, says Jim Carlson, CEO of Carlson Wireless, a startup in Arcata, California, that is commercializing white-spaces hardware. “We joked it would have been easier to launch a satellite,” Carlson says. “It’s like the whack-a-mole game—you fix three things and something else pops up.”
The FCC set very tight specifications to avoid interference, which means the technology has to operate at low power levels to satisfy the concerns of traditional broadcasters. The FCC also requires location-based databases to be built to guide the technology, because the available TV frequencies vary by location, and can change over time. Usage is only allowed when TV broadcasters don’t need them. Carlson has just “frozen” its design and applied for final FCC approval for commercial sale.
The other leading startup marketing white-spaces technology is Adaptrum, based in San Jose, California. It won FCC approval for an early version of its white-spaces transmitter and receiver technology in April, and is awaiting approval of an updated version. Adaptrum is supplying the West Virginia University installation.
Many smaller wireless Internet service providers (often called WISPs) are eager to use the technologies to serve rural pockets. “There are huge areas—half of the state of Texas, half of Illinois—where these WISPS all rely on unlicensed spectrum and use Wi-Fi to provide broadband,” says Michael Calabrese, director of the Wireless Future Project at the New America Foundation, a public policy group in Washington (see “4G on the Baby Monitor Frequency”).
White-spaces technology promises to extend the reach of these companies. “They have been huge advocates of TV white spaces—it’s much more economical and effective” than using cellular networks or satellite connections, Calabrese says.
White-spaces transmitters include a GPS chip and connect to an online database to determine what frequencies can be used at that location. Three U.S. companies have built such databases and have won FCC approval: iconectiv, Spectrum Bridge, and Google, which launched its FCC-approved database in March.
Microsoft is also working on such a database, but has been concentrating its efforts on deploying the technology abroad. In February, Microsoft partnered with a Kenyan telecom and the government to deliver white-spaces Internet to remote villages in Kenya that previously lacked both Internet and electricity. Several schools, libraries, agriculture offices, and health clinics are now being served. The company is also working in Tanzania and Singapore, among other countries. And Google is running its own African trials, in Senegal and South Africa.
In the U.S., the technology is seen as a way for rural public libraries to extend their reach. Some people park cars after hours outside libraries to catch Wi-Fi and check e-mail, says Don Means, who runs a project called Gigabit Libraries Network.
A Kansas City library is developing a white-spaces system to beam service to library “hubs” miles away. Other libraries in the nation are invited to apply for free equipment by August 12 to test the setup in their communities, Means says. He says the technology can provide workaday service: five-megabit-per-second speeds a few miles away at an extremely low cost. “It opens up another paradigm when it comes to wireless,” he says.
Other companies are trying to deliver broadband using the far higher frequencies that can inherently carry far more data, but are easily thwarted by obstacles, including rain. A leader in this area is Samsung (see “Samsung Says New Superfast 5G Works with Handets in Motion”)
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