Rosenworcel says she will propose a new look at standards for receivers as well as transmitters
The Federal Communications Commission will increase the available midband spectrum in the United States by auctioning 2.5 GHz spectrum this coming July, and follow that up with continued work on opening up 3.1-3.45 GHz, FCC Chairwoman Jessica Rosenworcel revealed in remarks at Mobile World Congress Barcelona.
“To support the next-generation of wireless connectivity, we must work together to free up more spectrum—and especially mid-band airwaves,” Rosenworcel said, according to her prepared remarks. “Because it offers an ideal blend of capacity and coverage, this spectrum is key to delivering on the promise of 5G services and ensuring that it reaches as many people as possible. The bottom line is we need mid-band deployment at scale to foster invention in the new 5G spectrum frontier.”
The U.S. focused on millimeter-wave spectrum in its earliest 5G auctions, though Rosenworcel made note of the midband spectrum that has already been auctioned domestically: The C-Band spectrum that operators recently began turning up (though not without attendant issues around potential interference with aviation systems), and the 100 megahertz of spectrum at 3.45-3.55 GHz that was auctioned in October 2021. She also said that the FCC is “taking a close look at the 4.9 GHz band and considering how it can be used for 5G services for public safety.”
Rosenworcel described the 2.5 GHz band as “the single largest swath of contiguous mid-band spectrum we have below 3 GHz,” adding, “The airwaves available in this auction are going to help extend 5G service beyond our most populated areas.”
Rosenworcel said that opening up new spectrum will be about a combination of a holistic government approach—nodding to a recent revamp of the relationship between the FCC and the National Telecommunications and Information Administration—and finding new technological approaches to spectrum usage.
“We face a hard truth. Greenfield spectrum—open and cleared for use—will not be as simple or easy to find,” said she. “We will have to invest in new technologies to promote efficiency and use a range of spectrum policy tools, including shared access, priority and preemption, lightweight leasing, and dynamic database coordination to ensure access to our airwaves.”
She also said that past discussions and rules around spectrum efficiency have “focused almost exclusively on transmitters” and how they are allowed to behave in order to control interference. “But here’s the thing,” Rosenworcel continued. “Wireless communications
only exists when transmitters are connected to receivers. Both are vital. Both matter. And
going forward, policymakers need to consider both transmitting and receiving. Not just the
former at the expense of the latter. That’s because minimally performing receivers can make it more difficult to introduce new services in the same or nearby frequencies. They can diminish broader opportunities with radiofrequency and put constraints on what is possible in the new wireless world.”
Which is exactly what happened and delayed the launch of 5G in C Band spectrum, where new terrestrial 5G operations raised fears of interference not because the stations themselves were transmitting improperly, but because of the concern that existing receivers in airplanes had been designed for operation in a very different radio environment and might not be able to filter out those newly introduced signals.
Rosenworcel said that she plans to propose a new FCC inquiry next month, to look into receiver performance and standards. Such a proposal may receive bipartisan support at the commission; FCC Commissioner Nathan Simington, a Republican, has previously voiced his support for at least the concept of setting standards for receiver performance—though he added the caveat that he hoped merely the discussion of such additional regulation might spur the industry to improve receiver performance on its own.
