Setting the stage for standard-power use of the unlicensed 6 GHz band, the Federal Communications Commission has officially approved seven applicants for automated frequency coordination (AFC) systems.
Systems from Qualcomm, Broadcom, Comsearch, Federated Wireless, Sony, Wi-Fi Alliance and the Wireless Broadband Alliance were all approved and can now move forward with managing spectrum access by Wi-Fi devices in the band.
“Automatic Frequency Coordination system operational approvals mark a major milestone for widespread deployment of unlicensed operations in the 6 GHz spectrum band and for the unlicensed ecosystem overall,” said FCC Chief Engineer Ron Repasi. “6 GHz standard power and fixed client device deployments under AFC control will expand access to new technology, applications and services. This is an exciting time for the industry, and for American consumers and business.”
When the FCC opened the 6 GHz band for unlicensed use, the FCC stipulated two types of operations: Low-power indoor operations and standard power operations. In order to avoid interference with incumbent fixed microwave systems and radio astronomy at a limited number of observatories, standard power access points and fixed client devices have to operate under the control of AFC systems in two portions of the band: The U-NII-5 band at 5.925-6.425 GHz and the U-NII-7 band at 6.525-6.875 GHz.
The FCC originally received 14 applications for AFC systems and had conditionally approved 13 of those; the 14th application, from Amdocs, with withdrawn. Now seven of them have received full approval.
The new AFC systems were approved after both lab testing and public trials with online AFC portals that were meant to give the opportunity to test the AFC system functionality. Users could specify test locations anywhere within the United States and get a list of the frequency ranges on which a standard-power device at that location could transmit, and the corresponding max power level. Users could then use that information to submit challenges to the AFC system.
Each of the public portals received more than 500 test locations, with the “vast majority” not resulting in challenges, according to the FCC. AT&T and the Electric Power Research Institute took a particularly active role in the challenge process, submitting challenges to all seven applicants.
The Commission noted in its public notice on the AFC approval that AT&T said that it “spent a significant amount of time working with the AFC applicants to identify the precise causes of the differences between the results calculated by the AFC systems and the results calculated by AT&T.” Sometimes that meant changes to AT&T’s calculations, and sometimes it resulted in modifications to the AFC systems. “AT&T observed that this process illustrated that reasonable engineers can differ with respect to how propagation calculations are implemented,” the FCC pointed out, and added that the modifications “modifications appear to be straightforward, such as not permitting standard power devices to operate in off-shore locations or outside the boundaries of the United States or adjusting the methodology used to determine the height to use in calculations involving passive microwave reflectors.”
The FCC also noted that the seven approved AFC applicants had expressed a commitment to establish a centralized way to receive and address harmful interference complaints resulting from AFC-authorized operations, and the agency conditioned their continued AFC operations on such a process being implemented by April 23, 2024.
 “The FCC’s approval of AFC operations for standard power 6 GHz Wi-Fi is a huge win for consumers, enterprises and service providers, alike. With expanded coverage and 63 times more power, standard power Wi-Fi will optimize our wireless experience indoors and outdoors, in crowded environments like stadiums,” said Chris Szymanski, director of product marketing for Broadcom’s Wireless Communications and Connectivity Division. He added, “As a founding member and co-chair of Open AFC, I am particularly gratified that Broadcom, Wi-Fi Alliance Services Company and Wireless Broadband Alliance have been authorized as AFC operators. We are optimistic Broadcom’s visionary work on Open AFC will deliver on the promise of 6 GHz Wi-Fi, ushering in a revolution of next generation connectivity.”
“We are delighted our work on AFC has resulted in our approval as an AFC Operator, and the collaboration on OpenAFC has been instrumental in the development of our AFC platform,” said Tiago Rodrigues, CEO and president of the WBA. “The WBA has been working with its members for over four years to see its vision for combining Wi-Fi 6E, 7 and 6 GHz AFC become a reality, as AFC is a critical component for the use of standard power on 6 GHz. The WBA will continue to champion the deployment of these standards globally, and we encourage all telecoms operators and Wi-Fi vendors to get involved in deploying AFC to maximize the benefits of using new spectrum on the 6 GHz band.”
