The FCC said it has reached a key target of potential available spectrum in its upcoming auction of broadcast airwaves, an indication of robust interest among TV stations.

The agency said that it had reached a 126 MHz target after stations made commitments last month to participate in the unprecedented auction of airwaves, which will be auctioned off over the next several months to firms for wireless use.

“Today’s announcement reflects the voluntary decision by many broadcasters that this auction truly is a once-in-a-lifetime opportunity,” said FCC chairman Tom Wheeler. “The 126 MHz initial clearing target ensures that wireless carriers and other forward auction bidders have their chance to compete for the maximum amount of low-band ‘beachfront’ spectrum.

“The broadcasters have stepped up and done their part to fulfill that demand,” he added.

The FCC had set a number of clearing targets before the auction process began, and an agency official expressed satisfaction that the 126 MHz had met their highest goal.

The auction depends on broadcasters deciding to offer up their spectrum, as the agency needs to clear enough of the airwaves to auction to wireless firms. The stations may choose to go off the air, share spectrum with another entity or move to a lower part of the spectrum band.

The bidding in the reverse auction — the initial phase of the complex auction process — will begin on May 31. There will be mock auctions on May 25 and 26.

Preston Padden, who led a coalition of companies interested in participating in the auction, said that the 126 MHz “far exceeds early estimates of likely broadcaster participation.”

He credited the figure to “years of hard work by the FCC commissioners and staff.”

The “reverse” auction will be followed by a “forward” auction in which companies will bid on spectrum for wireless use.

The exact number of stations making commitments was not disclosed.