(Telecompaper) The US Federal Communications Commission (FCC) has delayed its incentive auction to early 2016 from mid-2015, saying that legal challenges have bogged down the progress. FCC chairman Tom Wheeler said earlier that challenges to the auction rules by some broadcasters had introduced uncertainty, and a court briefing schedule now says final briefs will not be due until late January. Oral arguments will follow at a later, yet to be determined date, with a decision not likely until mid-2015. The FCC said that while it is confident it will prevail in court, the schedule means the auction must be delayed. The commission adopted the Report and Order in May and initiated rule-makings to address the operations of important services affected by the incentive auction, including unlicensed white spaces devices, wireless microphones and Low Power Television. The FCC believes it will vote on the Comment PN before the end of the year, which will propose and seek comment on the detailed directions for how the auction will be conducted. This will include the methodology to be used to establish opening bids for the reverse and forward auctions, how to define "impaired" markets subject to interference, and the components of the final stage rule. In the coming weeks, the commission will also consider a notice of proposed rule-making to preserve one vacant TV channel post-auction for use by unlicensed devices.