FCC opens 6 GHz band to very-low-power (VLP) unlicensed devices amid interference concerns

FCC commissioners today unanimously approved the use of very-low-power (VLP) unlicensed devices to operate in the 6 GHz band that many critical-communications officials consider to be the foundation of mission-critical and business-critical networks’ backhaul solutions.

FCC Chairwoman Jessica Rosenworcel cited the importance of unlicensed devices to the U.S. economy and society at large, with Wi-Fi technology serving as the final wireless link to a variety of end-user devices, from laptops to baby monitors and wearables fitness trackers. Expanding unlicensed use in the 6 GHz band is an important component to continuing this connectivity momentum, she said.

“Today, we take the effort to support unlicensed activity in the 6GHz band even further,” Rosenworcel said during the meeting. “We are opening up 850 megahertz of the 6 GHz band to small mobile devices operating at very low power, while putting in place common-sense safeguards to protect incumbent uses. We are also proposing to open up an additional 350 megahertz of the 6 GHz band for very-low-power devices.

“That means we are expanding access to the 6 GHz band to help jumpstart the next generation of unlicensed wireless devices. So get ready. Because we have now the unlicensed bandwidth, with a terrific mix of high capacity and low latency, that’s going to deliver new immersive, real-time applications. That means these are the airwaves where we can develop new wearable technologies and expand access to augmented and virtual reality.

“In other words, these are the airwaves where the future happens—and with the 6 GHz band, the United States is leading the way.

FCC Commissioner Brendan Carr expressed support for the item and said he would have hoped that it also include the use of higher-power devices in the 6 GHz band.

“I’m very glad that we are unanimous in taking action today in 6 GHz in a way that authorizes VLP operations,” Carr said during today’s meeting. “I know that there have been some over the years that have tried to get the FCC to backtrack on that issue, and to them, I say, ‘That’s not happening.’

“If anything, I think we need to more forward with more unlicensed permissions in the 6 GHz band. That’s why I would have been happy to go even further in today’s decision than we do right now. For instance, I would have preferred the FCC address higher power level right now for low-power-indoor—LPI—devices. I would have preferred authorizing VLP operations in additional portions of the 6 GHz band today.”

FCC Commissioner Nathan Simington also supported the 6 GHz band, but he acknowledged some of the interference concerns raised by representatives of incumbent users of the airwaves, including public-safety agencies and critical-infrastructure entities.

“What concerns me about today’s item is that it does not give adequate consideration to arguments made by commentators who raised concerns about lack of access to crucial data that informs those simulations and the potential of harmful interference to their operations from unlicensed VLP devices,” Simington said during the FCC meeting.

Simington urged the FCC to “proceed with caution” at 6 GHz, noting his fear that interference in the band could create a potentially unwieldy situation for incumbent users of the spectrum and for the FCC.

“If my fears bear fruit, the Commission could find itself in the position of attempting to police interference rights in a heavily congested environment where it proves difficult—if not impossible—to enforce its rules,” he said. “If 6 GHz licensees are unable to identify the source of interference, they will be unable to file a complaint with sufficient information to allow Commission staff to conduct any enforcement.”

One of the organizations that repeatedly has expressed concern repeatedly about the potential of interference in the 6 GHz band has been the Enterprise Wireless Alliance (EWA).

“The interference potential of VLP devices that are not associated with an AFC [automated frequency coordination] and that will be operated outdoors as well as indoors continues to be of concern to EWA,” EWA President/CEO Robin Cohen said in a statement provided today to IWCE’s Urgent Communications.

“We appreciate that the Commission acknowledged the interference concerns of the incumbents during today’s meeting, as well as its recognition that it has not addressed a process for identifying and reporting interference. We hope the FNPRM takes that issue into consideration and identifies a process for resolving those situations.”

Also outspoken about the potential interference that unlicensed use at 6 GHz could cause for incumbents is the Association of Public-Safety Communications Officials (APCO)—a position reiterated today by a APCO CEO Derek Poarch.

“APCO’s sole interest in this proceeding is to ensure the uninterrupted availability of the 6 GHz band for vital public-safety communications,” Poarch said in a prepared statement provided to IWCE’s Urgent Communications. “Yet so long as the [Federal Communications] Commission refrains from addressing the multitude of concerns, studies and questions that APCO and other incumbents have addressed in the record, APCO continues to have significant reason to believe that public-safety operations will suffer harmful interference that will be nearly impossible to resolve.

“Today’s action only heightens these concerns. At a minimum, it is imperative that the Commission act on incumbents’ request to explore a cost-recovery framework, so public-safety agencies aren’t  left footing the bill for dealing with degraded system performance and interference that requires new equipment or alternative means of communication.”

Indeed, APCO officials were clear about this 6 GHz interference concern when talking about the subject at the organization’s annual meeting in August, which was conducted in Nashville, Tenn.

Mark Reddish, APCO’s senior counsel and manager of government relations, said APCO strongly opposed the FCC’s 6 GHz order that allowed unlicensed uses in the band, but those efforts proved to be unsuccessful. As feared by many in public safety, even the lower-power routers at 6 GHz have created issues for mission-critical communications, he said.

“This is a very hot topic in the community, because—right now—the devices are relatively new routers,” Reddish said during a session at the APCO 2023 event. “They can use so much more spectrum than the old type of device, so I really think there’s going to be a hockey-stick [shaped] growth in the penetration of these devices.

“And the more that are out there, the more problems there are going to be for microwave systems in public safety.”

This is particularly troublesome for the public-safety community, because the 6 GHz spectrum band is widely used for microwave links that are key components in a number of mission-critical systems, according to Reddish.

“It’s used in the public-safety community for microwave links for backhaul—the backbone of public-safety communications,” he said. “We have microwave supporting our LMR networks’ first-responder radio communications. We have microwave networks connecting ECCs to one another for backup. So, it’s critically important spectrum supporting these links.”