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The DOD vs. Wi-Fi?

According to a story in the New York Times, the United States Department of Defense (DOD) is moving to get technical limits placed on the use of some unlicensed radio frequency spectrum (currently not used in the United States) because products that utilize it could, according to the government, interfere with military radar.

The article says officials from major companies like Intel and Microsoft have been meeting with the DOD this week to try and prevent the DOD from going forward with their plans. These companies, many others -- including the Pentagon according to the Times-- feel that of the unlicensed spectrum for products like wireless LANs is one of the few bright spots in the otherwise gloomy technology business.

The DOD is claiming that low-power radio emissions like those from a WLAN can jam up to ten different types of radar used by the US military for tracking everything from storms to guided missiles. To date, the Federal Communications Commission (FCC) has had no reports of a civilian wireless LAN interfering with military equipment.

There's a reason for this, says Dennis Eaton, the chairman of the Wi-Fi Alliance.

"It's a little bit of old news," says Eaton of the Times story.

The DOD's move is based on a petition the Wi-Fi Alliance filed with the FCC in January 2002, seeking to free up the middle chuck of the 5GHz radio frequency band for use in 802.11a equipment. This usage is allowed in Europe and other areas of the globe, but not in the US. Its simply an effort to harmonize spectrum allocations around the world.

The Pentagon wants to prevent opening the additional 5GHz band radio frequencies for use by WLAN equipment and more use of dynamic frequency selection technology in Wi-Fi products to avoid interference with military equipment. Such safeguards are already in place in European deployments of 802.11a equipment.

Eaton says the involvement of companies like Microsoft and Intel are not as altruistic toward the growth of Wi-Fi as it may appear. It is in every WLAN vendor's interest to see spectrum harmonization for the entire world, so they can make one product with one SKU [Stock Keeping Unit -- a unique number associated with a product for stock keeping] that will work everywhere.

"They don't want a European product and another for the US only," says Eaton. "That's a potential barrier to adoption. It's in their interest to make it as simple as possible."

The DOD position was presented at the World Administrative Radio Conference in Geneva this month. The World Administrative Radio Conference is the body that globally oversees allocation and standards for radio frequency use. The issue was included in the conference planning document as a footnote, despite dispute from European governments. Europe has a head start on the US in dealing with interference issues: the European Telecommunications Standards Institute (ETSI), the European equivalent of the FCC, requires testing for any radio products and has a provision in place to make sure they avoid radar and communication interference.

Some US lawmakers (Senator Barbara Boxer, D-California and Senator George Allen R-Virginia) had last month promised a bill in the next session of Congress that would expand the radio spectrum for wireless Internet usage.

Even if the DOD and Pentagon convince the FCC not to allow use of the middle portion of the 5GHz band, Eaton says it will have little or no impact on existing allocations or existing technology. The use of that area of the spectrum "is for expanding the scope" of Wi-Fi, he says. "If the DOD is successful, it doesn't change the current market. It just makes it more difficult for manufacturers so they must know what regulatory domain they're operating in and what products need multiple SKUs."

Eric Griffith is the managing editor of 802.11 Planet.

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