Microsoft says TV 'white space' usable without interference

Stephen Withers
Tuesday, 14 August 2007 03:10

IT Policy - Regulation

Microsoft is pressing ahead with plans to use vacant TV spectrum for wireless services.

The idea is to employ unused TV channels - 'white space' - for purposes such as broadband Internet.

The FCC plans to set standards for the unlicensed use of these frequencies for personal use and for commercial services, but is expected to require that the devices are able to identify which frequencies are available in the area they are being used and to avoid causing interference with broadcast signals.

TV stations cannot use every channel to service a particular area because that would lead to interference between geographically adjacent stations using the same channel. Consequently, there are several spare channels in any given area. The trick in putting those channels to other uses lies in ensuring that the devices do not interfere with the TV signals or other legitimate applications.

It seems the original prototype submitted by Microsoft to the FCC had a faulty component that caused some interference, but that a newer version operated successfully.

A Reuters report quotes a statement from Microsoft as saying "We remain confident that the unused channels in the television spectrum band can successfully be used without harmful interference to incumbent licensees such as television and wireless microphone services."

FCC officials said the technical requirements should be finalised by October, but devices would not go on sale before the analogue TV shutdown begins in February 2009.