To date, the tests have resulted in mixed results as early attempts to demonstrate the successful use of devices over the spectrum have generally failed, although Motorola claimed that one recent test "showed that multitiered approach to protecting incumbent users and TV white space area was successful."
The so-called "white spaces" refers to the portion of the ether alongside the 700-MHz bands that were auctioned off earlier this year to cell phone service providers in preparation for the wholesale move of analog television out of the 700-MHz space.
While Motorola has been claiming success in the tests, another strong supporter of the use of white spaces, Microsoft, has stopped participating, although the software colossus continues to support the use of white spaces.
Opposition to the use of the spectrum has been led by many broadcasters and some device manufacturers, claiming that plans for the use of the spectrum would create havoc for users and audiences of wireless microphones. One opponent has been device maker Shure, which in an FCC filing has stated: "If reliable interference protection cannot be demonstrated in the FCC spectrum sensing tests, the Commission should once and for all state that it will not approve new portable devices in the television band."
The FCC is attempting to get to the bottom of the issue with a series of tests begun in recent days in Maryland. In addition to the proposed test at the Lollapalooza festival on Aug. 1, the National Football League and ESPN have proposed that football stadiums be used for field testing.
A Motorola device tested at the Baltimore-Washington International Airport worked well, according to Bruce Oberlies, senior director of advanced technology and strategy at the company.