Arguing that the FCC’s decision to allow operation of unlicensed wireless devices in the digital TV white space bands will result in harmful interference to broadcast transmissions, the National Association of Broadcasters (NAB) and the Association for Maximum Service Television (AMST) petitioned the D.C. Circuit Court of Appeals last Friday to vacate the FCC’s order on grounds that it is arbitrary and capricious. Over the objections of television broadcasters and operators of wireless microphone facilities, the FCC adopted the white spaces order last November with the goal of opening a new platform for fixed and mobile wireless broadband services, especially in rural areas. To protect adjacent broadcast and wireless microphone operations, the order specifies that unlicensed portable devices that rely on geolocation technology would be able to operate in the white space bands subject to FCC equipment certification, with devices that use spectrum-sensing technologies to undergo further “proof of performance” tests in the lab and in the field before they are approved by the FCC. Although the FCC promised in its November 14 order “to take whatever actions may be necessary to avoid, and if necessary, correct any interference that may occur,” NAB told the court that, “as several engineering tests have shown, portable, unlicensed personal device operation in the same band as TV broadcasting continues to be a guaranteed recipe for producing interference.” Along the same vein, AMST added that, “one of the key issues . . . is that the data that was presented to the Commission and reported in the engineering report clearly demonstrates that spectrum-sensing will not protect over-the-air television reception.” Representatives of the wireless microphone industry are also expected to pursue similar legal claims before the Second Circuit Court of Appeals.