Rick Kaplan, executive vice president of strategic planning for the National Association of Broadcasters, said he's worried that broadcasters still need assurances from the FCC around how the upcoming incentive auctions will work. 

"One challenge is you want to be able to trust what you hear from the Commission," Kaplan said, during a panel at the Competitive Carriers Association (CCA) Expo in San Antonio. He added that broadcasters may think twice before putting their airwaves on the block without assurances that the FCC's rules for the auction won't be changed halfway through the process. 

"The bottom line is it a process where broadcasters can engage and trust that things are going to come out at the other end in a certain way," Kaplan said.

The comments were part of a panel that also included representatives from Sprint, T-Mobile, Dish, and C Spire Wireless. 

Overall the participants seemed to agree that the commission will come public with some new rules for the auction during its meeting in May. 

Kathleen Ham, vice president of federal regulatory affairs for T-Mobile, said the upcoming broadcast incentive auction, which has been pushed out to 2015, will be critical for competition in the wireless industry. 

T-Mobile, Sprint and other regional carriers are particularly concerened that AT&T and Verizon are note allowed to dominate the auction. The panel's consensus seemed to be that the nation's two largest carriers have resources that would allow them to snag the bulk of the valuable spectrum that will be put up for bid. 

Today's discussion echoed the sentiments of a letter sent this week to the FCC by CCA members, including T-Mobile and Sprint, that outlined sugestion for exactly how the FCC should proceed in designing the upcoming 600 MHZ auction.  

That letter highlighted the need for aggregation limits on spectrum below 1 GHz; the need for clear limits in place prior to the incentive auctions; the need for rules to address market realities; and the need for a weighting policy for spectrum in all bands.

“These principles are not the only mechanisms necessary for a successful auction, but are important guidelines that emerged as the consensus view among our diverse group of stakeholders,” the group wrote in the filing.