• 11GHz of mmW spectrum to be made available across four bands
• Includes the 28GHz band which is not currently being considered by WRC
• Proposal to add a further eight mmW bands and 18GHz in the future
• US Army contributes to mmW testing

The FCC yesterday adopted new rules for wireless broadband operations in frequencies above 24GHz, formalising chairman Tom Wheeler’s “spectrum frontiers” proposal. As expected, the new rules open up just under 11GHz of millimetre wave spectrum, split between 3.85GHz for licensed spectrum and 7GHz for unlicensed. The new bands for “Flexible Use” service are 28GHz (27.5-28.35GHz), 37GHz (37-38.6GHz), and 39GHz (38.6-40GHz), and a new unlicensed band at 64-71GHz. There are more details about the US mmW spectrum position, compared to that of Europe, here on TelecomTV.

Chairman Wheeler is keen to push the US as a champion of future 5G services and as such wants additional spectrum to be made available for use sooner rather than later. It’s an interesting strategy, given that mmW 5G applications and services, let alone the new radio access technology and core network support, won’t become commercially available until after 2020. The first real implementations of 5G will be on existing spectrum and sub 6GHz, and may well be delivered via the next version of LTE Advanced Pro as part of 3GPP Release 14. Globally harmonised mmW spectrum will have to wait until after the ITU’s WRC regulatory meeting in late 2019. In practical terms, it’s going to be the mid-2020s before mmW takes off.

Still, Wheeler can claim his world first. Whether or not US industry can capitalise on this move is another thing entirely. After all, the FCC still has to auction this spectrum to interested parties. Still, this week’s rules set the foundation for the inevitable multi-billion dollar auctions.

The rules cover different spectrum access approaches, including exclusive use licensing, shared access, and unlicensed access, in order to meet a variety of different needs and use cases.  The FCC also adopted other flexible service and technical rules to allow new technologies and innovations to evolve without prescriptive regulations. The 278-page Report and Order is available here, if you are in need of some weekend reading.

In addition, the FCC says it will continue to explore new opportunities to make additional bands available at some future point. It wants to apply the flexible use service and technical rules adopted yesterday to another 18GHz of spectrum encompassing eight additional high-frequency bands between 24GHz and 80Ghz. It also seeks comments on the use of bands above the lofty heights of 95GHz.

The problem for the FCC, and one that is shared by many other countries, is that the new mmW bands are – to a greater or lesser extent – already used by other bodies, including Federal agencies. In the US, some of the new bands already have incumbent rights attached and may present rather difficult sharing issues. Hence the need to adopt rules to start the long process of unravelling and resolving rights issues, clearing the way for future 5G services in these bands. Nothing is going to happen overnight, and this important development – and it is important – is perhaps being misinterpreted in some quarters (not helped by Wheeler’s rather political cry of “rah, rah, America first”) as the start of high-frequency 5G services – it’s not. Still, there was an appropriate patriotic response from the industry:

“The FCC's decision today to make thousands of megahertz of high frequency spectrum available will be a critical building block in our country’s 5G future,” said Craig Silliman, Verizon’s general counsel and executive vice president for public policy. “The decision to make this spectrum available for commercial use right now will help ensure that the US maintains its leadership position in wireless communications.”

“5G Americas supports the FCC’s ongoing study of an additional 17.7GHz of spectrum, as proposed in today’s Further Notice of Proposed Rulemaking, as well as in industry bodies, to fulfil the ‘national priority’ of American leadership in 5G set forth by today’s historic event,” said Chris Pearson, President of 5G Americas.

“With the adoption of these rules, the Commission has created a runway for US companies to launch the technologies that will harness 5G’s fiber-fast capabilities,” concluded the FCC’s media statement. Individual commissioners have been unusually quiet, though we expect a flurry of personal statements later today.

Tucked inside the Report and Order document was an interesting nugget of information. It concerns the mmW technology trials conducted in New York a few years ago, that we often cite on TelecomTV as evidence of the viability of using high-frequency signals in built-up environments with non-line of sight issues and plenty of propagation obstacles. These were the trials that found that 39GHz mobile base stations can sustain 100 per cent coverage in cells with a 200-meter radius in high-density urban areas.

It turns out this was achieved by capturing reflections of signals that would otherwise be blocked by intervening obstructions. Receivers equipped with highly directional, steerable antennas were able to capture and combine as many as 14 links with rooftop-mounted transmitters despite obstructions in propagation paths. Furthermore, it was revealed that these trials were jointly funded by Samsung and the US Army. Time to include "military" as one of the 5G vertical market use cases perhaps?