The FCC unanimously voted to adopt new rules related to the spectrum above 95 GHz that encourage the development of new technologies—and may even lead to 6G.
Once thought to be more or less useless—similar to how much of the industry used to think of the millimeter wave spectrum that’s now being deployed for 5G—these super-high spectrum bands are now viewed as offering opportunities for innovation, especially for data-intensive, high bandwidth applications as well as imaging and sensing operations.
FCC Chairman Ajit Pai invited NYU Wireless Professor Ted Rappaport, who was instrumental in conducting ground-breaking millimeter wave research, to present his institution’s findings thus far on the opportunities afforded by the spectrum bands above 95 GHz, where “science fiction will become reality,” Rappaport told the commission.
The applications that become possible at these higher frequencies are kind of mind-blowing, he said. With so much bandwidth and wider bandwidth channels, you can start having data rates that approach the bandwidth needed to provide wireless cognition, where the computations of the human brain at those data rates could actually be sent on the fly over wireless. As such, you could have drones or robotics receive in real time the kind of perception and cognition that the human brain could do.
The conventional wisdom is that as you go higher in frequency, you get more loss. “That’s only if you use an omnidirectional antenna, the old way of doing cellular 10 and 20 years ago. When you start using directional antennas, what happens is, you actually do better as you go higher in frequency for a given power level and a given antenna physical size,” Rappaport said.
To enable innovators and entrepreneurs to most readily access this spectrum, the FCC’s Spectrum Horizons First Report and Order creates a new category of experimental licenses for use of frequencies between 95 GHz and 3 THz. These licenses will give innovators the flexibility to conduct experiments lasting up to 10 years, and to more easily market equipment during the experimental period, according to the FCC.
“Today, we take big steps towards making productive use of this spectrum,” Pai said in his statement. “We allocate a massive 21 gigahertz for unlicensed use and we create a new category of experimental licenses. This will give innovators strong incentives to develop new technologies using these airwaves while also protecting existing uses.”
Commissioner Jessica Rosenworcel said it’s worth noting that the spectrum in these higher bands is different from the lower bands in that it’s subject to the authority of both the FCC and the National Telecommunications and Information Administration (NTIA), and that requires more meaningful coordination among the federal partners.
Fellow Democratic Commissioner Geoffrey Starks also noted that the terahertz spectrum imaging could change the way doctors and researchers understand biological processes on the cellular level and doctors may be able to use the technology to conduct noninvasive cancer screening tests. In security settings, terahertz spectroscopy can be used to identify dangerous materials and weapons, meaning threats to safety can be identified without body scams.
But he added that he has serious questions about the FCC Enforcement Bureau’s tools to detect interference in these and other high-frequency bands. It’s not currently capable of policing a significant amount of millimeter wave spectrum, which is being used for 5G, and he’s concerned that without sufficient resources for modern enforcement tools, efforts will be undermined.
While voting for the order, Commissioner Michael O’Rielly said the FCC’s action on this spectrum in no way reduces the need for making more unlicensed allocations of spectrum and he pointed to two items in particular—revisiting the 5.9 GHz band and taking steps to open the 6 GHz band for unlicensed use—as ways the commission can address that.
In a statement provided to FierceWireless, Rappaport said he was honored to be invited by Chairman Pai to be part of the historic vote to open up spectrum above 95 GHz for the first time in the history of the United States.
"The vision and hard work by Chairman Pai, the commissioners, the FCC staff, and past work by Chairman Wheeler, have kept the U.S. on the cutting edge of 5G, ensuring that our country will enjoy the vast applications and efficiency it will provide,” he said. “Now, with the Spectrum Horizons initiative and this historic vote, the FCC has launched the race to 6G, helping to ensure the U.S. will play a leading role in future generations of wireless."
"President Trump mentioned 6G a few weeks ago - perhaps the first world leader to do so. As an engineer and educator, I'm happy to know our country's leaders are working to support American competitiveness in Science, Technology, Engineering, and Math (STEM),” Rappaport said. “STEM and engineering research are so vital for our country's economic future, and it needs attention like the President gave to 6G."