Skip to main content

White Space: Motorola Tests Prototype, NAB Pushes Back

Motorola has thrown a white space prototype into the ring, showing FCC engineers a device it says dynamically scanned RF spectrum for DTV signals to show it could operate without causing interference.

Aug. 30, about 15 Motorola personnel demonstrated the device to about a dozen FCC staffers, according to a filing by Motorola describing the encounter.

Motorola says its device, aided by an FCC geolocation database, showed it was capable of detecting a newly active DTV signal and immediately re-establishing communication on a different channel. The company said there are also various ways to protecting the wireless microphone operations.

“Motorola’s demonstration clearly showed the viability of an approach that combines geolocation database information and spectrum sensing without adding undue cost or processing burden,” the company wrote.

This summer, the FCC tested prototype technologies from Microsoft and Philips that could become the backbones of so-called white space devices, such as wireless networking products, that operate on unused frequencies in the DTV spectrum. Microsoft has said its prototype’s poor result was caused by a defect in the box; Philips has said that minor adjustments made the performance of its box even better than when the FCC tested it.

Motorola is not a member of the White Spaces Coalition, a group of eight high-tech companies fighting for rules that would allow mobile devices in the DTV spectrum.

NAB, meanwhile, is fighting back. Monday, Sept. 10, NAB will hold a press conference, along with executives from the broadcast industry, big-time sports leagues and consumer electronics companies, to detail the problems with white space devices. NAB has recommended the FCC make rules allowing only fixed—not mobile—white space devices.

Sept. 6, the Association for Maximum Service Television (MSTV) touted a letter from Spanish-language broadcasters Univision, Telemundo, Entravision, TuVision warning against potential interference from white space devices.

“Potential harmful interference from these unlicensed and portable devices could jeopardize a smooth and successful DTV transition, with particularly serious consequences for Hispanic households across the country,” MSTV said. “Hispanic viewers have a great deal at stake in the transition, as they have always relied more heavily on over-the-air TV reception than the general population.”