US in the Ballgame on Ultra-High Band, Initial Allocations Small: NYU's Rappaport

Ultra-high band spectrum remains a “wild, wonderful and challenging” world, said Ted Rappaport, director-NYU Wireless at New York University School of Engineering, during a National Science Foundation webinar Wednesday. The FCC tapped Rappaport to speak on the importance of spectrum above 95 GHz before a vote last year approving the spectrum horizons order (see 1903150054). Some are looking to spectrum as high as 700 GHz, he said. Commissioners will consider an NPRM on the 70, 80 and 90 GHz bands at their June 9 meeting (see 2005190058).

With last year’s order, the U.S. is “in the ballgame for the first time ever in frequencies above 95 GHz,” Rappaport said. The FCC opened up some bands that are “relatively narrow, a maximum of 7 GHz,” he said. “While the FCC took a bold step … as have Europe and Asia, there’s a relatively small amount of spectrum allocated compared to what’s available,” he said. “We’re looking at frequencies that really are new, but there’s a lot of investment.”

A challenge remains to protect “vital interests” in space and on the ground, Rappaport said. There’s also the question of potential health effects as frequencies get closer to the ultraviolet and X-ray range, he said: “We have to know with much better knowledge than we do now how safe these devices above 100 GHz are.” Another challenge is high-band signals degrade quickly at altitude, he said. He cited opportunities beyond fixed wireless to "other things like wireless cognition, sending information at the rate of the human brain over wireless, sensing.” Smartphones could be used to figure out where someone is within centimeters, he said.

Spectrum policy doesn’t have to be a “zero-sum game,” said consultant Michael Marcus. “Creative solutions can allow sharing that wasn’t possible with the original design concepts.” The usual argument incumbents make is all possible designs will cause harmful interference, he said: “That’s a useful trick to lawyers, but it’s really disgusting to technologists.” Policy determines whether a technology can be used, he said.

The main ultra-high band sharing issue isn’t with radio astronomy, which has antennas in only a few locations in the U.S., but with satellites, Marcus said. If the “frequency you want to use is used by passive satellites, you have a problem everywhere,” he said: “Being in an experimental zone doesn’t help.” Propagation and wavelengths are very different than in lower bands, he said. “It’s not VHF, with a few extra zeroes,” he said: “A lot of people who understand VHF and UHF extrapolate their understanding of radio from that, and at some point it falls apart.”

Bert Hawkins, head of the National Radio Astronomy Observatory’s Central Development Lab, said its “signals are so much different, we have to spend so much time staring at them … even to get the signals.”

CBRS

During a FierceWireless webinar Wednesday, speakers predicted a bright future for the citizens broadband radio service band, though challenges also remain in the 3.5 GHz band.

Mark Duebner, director-aviation at Dallas Love Field, said the facility did a successful test of CBRS, but there are challenges, especially in older buildings. “Deploying all this additional equipment, cabling and having the ability to run new stuff … that started to get crowded,” he said: “The challenge is really going to be where’s your backhaul?” The airport realized it may need to redesign its buildings, which is expensive and takes time, he said: “We’re starting to layer upon layer, upon layer, which is really not the best way to do.”

Amdocs, which received FCC approval as a spectrum access system (SAS) administrator in April, doesn’t feel it's late. “We’ve always viewed CBRS as a marathon not a sprint,” said Senior Vice President Parag Shah. “We see CBRS as prime spectrum that’s going to drive a lot of innovation with private wireless networks.” The 3.5 GHz band offers an attractive balance of coverage and capacity, he said.

The pandemic is a game changer for CBRS, Shah said. “We’re seeing robots being used for social distancing and policing,” he said. “We’re seeing hospitals leverage new technology … to ease the burden on nurses.” Hotels have to “reinvent themselves” to be more automated, he said. In Israel, where the company is based, machines are taking people’s temperatures, he said. Can all this happen “on the networks that exist today or do we need something different and better?” Shah asked.

The biggest venues need a low-cost product for multiple operators, said Kyung Mun, principal analyst at Mobile Experts. Hundreds of thousands of buildings lack a dedicated system, he said. CBRS offers 150 MHz of new spectrum, he said. It offers “coordinated access,” unlike more traditional unlicensed, he said. It potentially can be installed more quickly than complex distributed antenna systems, he said.

The FCC has OK'd five SASs, plus a growing number of smartphones, laptop computers and tablets are CBRS ready, Mun said. He predicted a wide number of players will be interested in the priority access licenses to be auctioned by the FCC this summer, and LTE will be the “dominant” use.

Kaiser Permanente seeks CBRS and Wi-Fi 6. Wi-Fi will provide “that ubiquitous general connection that we use for wide-scale shared access,” CBRS “critical device connectivity,” said Kristan Kline, principal-network strategy. The healthcare system projects wireless data to eventually grow by five times over what’s seen today, with 13 times as much sensor data.