AT&T is asking the Federal Communications Commission (FCC) to avoid any expansion of the 6 GHz band to unlicensed users, noting that roughly 25% of the links in the band support public safety and critical infrastructure licensees. AT&T said that band contains about 100,000 microwave links, many of which are carrying critical voice and data traffic, including for the nation’s first responders.  AT&T added that introducing unlicensed devices would cause interference at the receive antennas of those microwave links, thereby reducing their reliability.

The telco estimates 27% of the links support utilities, making the upper and lower 6 GHz bands key in supporting the nation’s critical infrastructure. It also said that maintaining long-haul and high-reliability microwave links will be critical for 5G and other advanced services.

AT&T officials met last week with FCC staff to discuss its concerns about a proposed expansion of the 5.9125-7.125 GHz band to include unlicensed use. AT&T said it will be relying on a significant number of existing and newly developed 6 GHz fixed links in support of FirstNet [1.], where it’s contractually obligated to provide high levels of reliability.

Note 1.  FirstNet is the first nationwide U.S. wireless network dedicated to public safety.  AT&T won the contract to provide the wireless network for FirstNet last year.

AT&T’s letter to the FCC was made public in an ex parte filing. 

References:

https://ecfsapi.fcc.gov/file/10319087261781/6GHz-ExParte031618.pdf

https://www.fiercewireless.com/wireless/at-t-says-6-ghz-band-key-for-firstnet-5g