FCC casts an eye north of 95 GHz

The FCC has unveiled plans to create a new regulatory framework for spectrum above 95 GHz.

While these bands have largely been considered outside the realms of usable spectrum, progress in radio tech has made the prospects much more realistic. And, dare we say it, such a regulatory framework could begin to set the foundations for 6G…

“Today, we take big steps towards making productive use of this spectrum,” said FCC Chairman Ajit Pai. “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.”

The Spectrum Horizons First Report and Order creates a new category of experimental licenses for use of frequencies between 95 GHz and 3 THz, valid for 10 years. 21.2 GHz of spectrum will also be made available for use by unlicensed devices. The team envision usecases such as data-intensive, high bandwidth applications as well as imaging and sensing operations.

With this spectrum now on the table, the line between science fiction and reality could begin to blur. Data throughput rates will become almost unimaginably fast, meaning computational power in the wireless world could start to replicate the kind of performance only seen in human brains.

“One reason the US leads the world in wireless is that we’ve moved quickly to open-up new spectrum bands for innovative uses,” said Commissioner Brendan Carr. “We don’t wait around for technologies to develop fully before unlocking spectrum so that entrepreneurs have the incentives to invest and experiment.”

While such a statement suggests the FCC is doing a wonderful job, flooded with foresight, the industry tends to disagree.

In 2017, the mmWave Coalition was born. Although this is a relatively small lobby group for the moment, it does have some notable members already including Nokia and Keysight Technologies. This group has been calling for a regulatory framework above 95 GHz for 18 months, pointing to developments around the world and stating the US risks falling behind without amendments.

A good example of other initiatives is over in Europe, where the European Telecommunications Standards Institute (ESTI) has created the ISG mWT working group which is looking at how to make the 50 GHz – 300 GHz band work. This group has already been running trials with a broad range of members including BT, Deutsche Telekom, Intel, InterDigital and Qualcomm.

While the US is certainly taking a step in the right direction, it would be worth noting it is by no-means the first to get moving beyond the 95 GHz milestone. Europe is leading the charge at the moment.

However, Commissioner Jessica Rosenworcel believes the FCC is being too conservative in its approach.

“I believe that with these way-up-there frequencies, where the potential for interference is so low, we should flip the script,” said Rosenworcel. “The burden should be on those seeking exclusive licenses to demonstrate the interference case and justify why we should carve up an otherwise open space for innovation and experimentation.”

Rosenworcel points to the incredibly short-distance this spectrum will offer, as well as the creation of new antenna designs, like quasi-optical antennas, to ensure efficiency. With the shorter distance and better control of the direction of signals, interference does not pose a threat and therefore an unlicensed approach to spectrum should be prioritised.

Commissioner Michael O’Reilly is another who also supports this position.

“While I strenuously advocate for both licensed and unlicensed spectrum opportunities, I understand that it may be a bit premature to establish exclusive-use licenses above 95 GHz when there is great uncertainty about what technologies will be introduced, what spectrum would be ideal, or what size channel blocks are needed,” said O’Reilly.

Both of these messages effectively make the same point; don’t make assumptions. Taking the same approach to spectrum allocation will not work. The traditional approach of licensed spectrum allocation is perhaps unnecessarily rigid. It might be necessary in the future but granting innovators freedom in the first instance would provide more insight. Perhaps it would be better to react to future developments than to try and guess.

“Better that than being forced to undo a mess later,” said O’Reilly.

While it is of course encouraging the FCC is taking such a long-term view on industry developments, the team needs to ensure it does not over-complicate the landscape right now with unnecessary red-tape. Future regulation needs to protect innovation and grant the freedoms to experiment; a light-touch regulatory environment needs to blossom.