Despite Commissioners' Support, Wi-Fi in 6 GHz Band Faces Fight

Wireless industry lawyers said the interference questions could delay FCC action. “Anytime the commission must grapple with the possibility of harmful interference, the process always turns into a slog, most often measured in years,” said a former spectrum official. The agency didn’t comment.

The Association of American Railroads, Utilities Technology Council and other groups representing electric utilities and additional critical infrastructure companies, SiriusXM and public safety groups raised concerns (see 1902190005). Unlicensed advocates stressed the importance of more mid-band spectrum as the threat of Wi-Fi exhaust looms. UTC's comments "speak pretty clearly about our concerns" on the importance of AFC, a spokesperson said. "Our comments on the 6 GHz [band] speak for themselves," AAR said.

Chairman Ajit Pai has the votes for a “strong order” on the band, with public support from Commissioners Mike O’Rielly and Jessica Rosenworcel, said Michael Calabrese, director of the Wireless Future Program at New America. “The limiting factor is almost entirely technical,” Calabrese said. “Even the electric utility coalition articulated only half-hearted opposition to an automated frequency coordination system to manage unlicensed sharing, including outdoor deployments, of the 850 MHz they use for point-to-point data links.”

The commission's choice isn't whether to allow radio local area network (RLAN) operations, said spectrum/wireless tech Mitchell Lazarus of Fletcher Heald. The FCC can do that “while fully maintaining fixed microwave reliability,” Lazarus said. “The choice is whether to prioritize incremental improvements in unlicensed, opportunistic internet access in this particular band over the integrity of a licensed and ultra-reliable service whose applications include safety-critical services.” Lazarus represents the Fixed Wireless Communications Coalition, which commented that the FCC must protect the 96,604 fixed service links in the broader 6 GHz band.

"The technical contributions in the record already give the commission good reason to enable indoor low power operations throughout the entire 1,200 MHz,” said Chris Szymanski, Broadcom director-product marketing and government affairs. Others demonstrated that “low-power RLANs indoors will not lead to harmful interference to incumbent services,” he said. Comments by the Leading Builders of America show that any modern building is an energy-efficient building, “which means that the already vanishingly small possibility of potentially harmful interference is going to continue to decline further as new buildings are put up, or buildings are retrofitted,” Szymanski said.

The FCC has enough experience with database technology to be confident AFC “can coordinate sharing even more protectively than the traditional manual coordination still used among fixed incumbents in those bands,” Calabrese said. The key question is whether to allow “very low-power, off-the-shelf Wi-Fi routers and connected devices on an indoor-only basis” without coordination, he said: “It is certainly the one that will have the greatest impact on ordinary consumers and on the affordability of the connected home and other promised benefits of a 5G wireless ecosystem.”

AFC will be helpful, “but there are questions about how restrictive it will be,” said Joe Kane, R Street Institute tech policy fellow. “I think a lot will come down to actual tests to see how much and indoor signal penetrates windows, walls, etc.” AFC appears to be an easier system to run than dynamic frequency selection in some of the U-NII-2 channels, he said. Whatever the FCC decides, “I hope it allows for this band to actually be used for unlicensed,” he said. “Maybe whatever the compromise is could be extended down to 5 GHz to make a more harmonious unlicensed environment across that whole swath.”