FCC will keep testing white space devices

Oct 09, 2007 5:24 am
From Matthew Lasar in Lasar's Letter on the FCC:
Everybody had something to tell the Federal Communications Commission about so-called "white space" or "unlicensed" devices last week, including Cox Communications and the "Open Mobile Video Coalition."

The chatter culminated in Friday's decision by the FCC to initiate a new round of tests of the machines: cognitive receivers that can tap into unused television frequencies, or "white space," and use them for broadband purposes: video, streaming audio, extended LANs or "community mesh networks."

"The Commission is committed to working with all parties to continue the process of investigating the potential performance capabilities of TV white space devices in an open and transparent manner," the agency announced on October 5. "To that end, the Laboratory will be conducting additional laboratory and field testing of prototype devices."

The prototypes come from Microsoft and Phillips, big boosters of the technology and leaders of the "White Space Coalition," which also includes Google, Hewlett-Packard, and Intel.

Their FCC filings promise that "unlicensed devices operating in the TV band will offer longer transmission ranges using the same power, less risk of signal attenuation or harmful interference, and less power consumption at the same range than Wi-Fi."

TV broadcasters, on the other hand, have roundly denounced the technology, likening it to a potential epidemic spread by signal interference laden "germs . . . with the ability to attack the TV receivers in people's homes, apartments, hotel rooms, hospital rooms, dormitories, etc."

On September 21 Microsoft and Phillips submitted the results of their latest unlicensed device tests to the FCC. Their tests confirm that it is feasible for white space devices to pick up TV signals at a signal strength "that is far too weak for a television set to produce a broadcast television picture," their filing concluded.

But the broadcasters aren't letting up on this issue. The Open Mobile Video Coalition's October 2nd comment urges the FCC to test unlicensed devices for interference with mobile receivers [eg, cell phones], and "not to permit unlicensed devices to operate in the DTV spectrum unless there is fully effective protection against interference to the mobile broadcast service from mobile devices."

The filing is signed by reps from Tribune, Cox Television, Telemundo, Media General, Gannett, and Fox, among other broadcasters.

Independent of this group, Cox submitted several statements to the FCC on the same day, arguing that the "state of these cognitive radio technologies - as demonstrated by the [FCC's] laboratory tests - is too immature to ensure protection of broadcast and cable services."