The FCC said Monday it will auction off access to multiple chunks of wireless spectrum.

Why it matters: It's part of an aggressive push towards super-fast 5G wireless services, which require new swaths of airwaves to become available to the carriers building the networks.

The details: The FCC said it wants to hold two auctions — first of the 28 gigahertz band of airwaves and then of the 24 gigahertz band — starting later this year. These airwaves are in the higher frequency bands, meaning signals travel shorter distances and are often used in urban settings.

• The wireless industry's trade association praised the announcement, calling it "a critical next step to meeting the United States' 5G ambitions."

But but but: Congress has to pass a law sorting out some of the financial arrangements around spectrum auctions first, the agency says. It says that has to get done by mid-May for its timeline to work.