Scientists Debunk TV Band-Sharing Interference Allegations

MANHASSET, N.Y. — Three leading U.S. scientists have delivered a brief outlining why the unlicensed use of the white space in broadcast TV bands will not interfere with digital TV transmissions.

The brief counters interference allegations by broadcasters that have stalled a May 2004 initiative by the Federal Communications Commission to open up spectrum by allowing new wireless device such as Wi-Fi to operate in broadcast TV bands.

Long coveted for their long-range and building-penetration characteristics, the TV bands have often been referred to as a vast wasteland of underused spectrum.

According to the brief authored by two former FCC officials and a university researcher, even after the transition to digital broadcasts and the reallocation of TV channels 52 to 69, an average of only seven full-power DTV stations will be operating on channels 2 to 51 in the nation’s 210 local TV markets. As a result, only a fraction of the 294 MHz of prime spectrum allocated to DTV services will actually be used in most markets, the brief concluded.

The brief’s authors are well known.Michael Marcus is former associate chief for technology at the FCC’s Office of Engineering and Technology. Marcus retired after almost 25 years in senior policy positions dealing with spectrum issues.

Paul Kolodzy is former chair of the FCC’s Spectrum Policy Task Force and former director of the Center for Wireless Network Security at Stevens Institute of Technology. He is now a communications consultant.

Andrew Lippman was the founding associate director of the MIT Media Lab from 1983 to 2001. He currently co-directs the Institute-wide Communications Futures Program. He also directs the Viral Radio Program, which is exploring ways to use mesh architectures to develop energy- and spectrum-efficient scalable radio communications systems.

Their brief presented a series of arguments on why U.S. broadcasters' fears are unfounded or are readily avoidable using current wireless technologies. The brief also seeks to refute arguments against the use of the listen-before-talk protocol.

It also seeks to promote the use of geolocation and the automated checking of frequency assignments against a database that would be used both to identify and avoid channels is use in a particular area.0