Bidding in a US auction of 24GHz spectrum quickly surpassed the $702.6 million total recently achieved in the country’s first 5G auction, reflecting strong operator interest in unencumbered mmWave bands.

A week after it began, gross proceeds in the 24GHz auction hit upwards of $861 million at the close of 17 rounds of bidding.

Licences in New York City and Los Angeles drew the highest bids, with the top offer for the former coming in at $23.2 million and the latter $17.9 million.

Chicago and San Francisco followed, drawing top bids of $8.6 million and $8.3 million, respectively.

The fierce competition demonstrates strong interest in a mmWave band Wells Fargo Securities recently noted offers a “clean slate” for operators. Though a 28GHz auction held earlier in the year put similar airwaves on offer, Verizon already owned many of the major market licences in the band when bidding began.

AT&T, Verizon, Sprint, T-Mobile US and US Cellular are all listed as qualified bidders in the 24GHz auction.

Bidding follows the same format as the Federal Communications Commission’s 600MHz proceeding held in 2017, wherein an initial phase of offers on generic blocks in each market will be followed by an assignment phase during which winners can bid for specific frequencies.

Winners from both the 28GHz and 24GHz auctions will be announced at the close of the latter. A third mmWave sale of spectrum in the 37GHz, 39GHz and 47GHz bands is scheduled for later this year.