DALLAS – A top Google executive argued that the spectrum sharing and licensing model created by the FCC for the 3.5 GHz band could also be used to more quickly and efficiently deploy 5G networks. “We have to break the model of exclusive spectrum,” argued Google’s Preston Marshall here during a keynote appearance at the 5G North America trade conference.
Specifically, Marshall strongly argued against the current wireless network deployment model whereby carriers spend billions of dollars to acquire exclusive rights to spectrum bands covering whole U.S. cities or states, spectrum that could lie fallow for years while those carriers also obtain the financing to build out networks on that spectrum. He added that indoor locations on those bands may never be deployed due to the costs involved. Instead, he called for a “neutral host” buildout model where unused spectrum could be accessed by virtually any entity in a licensed or unlicensed scenario in chunks as small as a single floor of an office building.
“These are radical ideas,” Marshall acknowledged to a keynote audience full of executives who, in many cases, built their companies and careers on the notion of privately owned, nationwide wireless networks running on licensed spectrum.
In his presentation, Marshall argued that the traditional model of deploying bandwidth won’t work in the higher spectrum bands, like 3.5 GHz, that are being considered for 5G. Unlike lower spectrum bands like 700 MHz, higher bands like the millimeter wave bands above 28 GHz can’t transmit signals more than a few hundred yards in most cases. Thus, if the FCC implements spectrum sharing models on higher spectrum bands, as it has done in the CBRS 3.5 GHz band, Marshall predicted that a large number of 5G deployments “may not be MNO led,” but would happen much more quickly.
He said that, under such a scenario, venues, private companies and individual users could deploy their own 5G networks as they do with Wi-Fi networks today. And network operators could offer their customers access to those networks. “Everyone kind of benefits from this,” he said.
Marshall added that neutral host networks – where any private entity can build out a local network and then offer that service to anyone with a suitable receiving device – are the “killer app” in the nascent but growing 3.5 GHz ecosystem. He said that the addition of 3.5 GHz capabilities to small cells and Wi-Fi hotspots will add no more than $50 to the cost of those devices, which he said ought to encourage the 3.5 GHz ecosystem to grow.
And, Marshall said, all of the business model and technological issues currently being ironed out in the 3.5 GHz sector “are identical in 5G.” Marshall added that he expects to publish a book on the United States’ progress on 3.5 GHz spectrum sharing and licensing early next year, with the goal of encouraging European countries to embrace the model.
Marshall’s comments don’t come as much of a surprise. Indeed, Google for years has pushed the FCC to release more unlicensed spectrum. Partly in response, the FCC last year freed up 150 MHz of spectrum in the 3.5 GHz CBRS band with the understanding that it would be shared among licensed and unlicensed users via a spectrum-sharing scenario similar to the one used within TV white spaces spectrum bands.
Specifically, the FCC hopes to implement a Spectrum Access System (SAS) in the 3.5 GHz band – the agency is now in the process of hammering that SAS out, which will make it possible to share spectrum where it hasn't been before. Google and Federated Wireless are two companies interested in handling SAS coordination and database administration, a key element for a spectrum sharing system.
And, earlier this year, the CBRS Alliance was formed by six companies – Access Technologies (Google), Federated Wireless, Intel, Nokia, Qualcomm and Ruckus Wireless (now part of Brocade) – with the belief that “access to LTE-based solutions in the US 3.5 GHz frequency band will be a critical tool to meet rapidly expanding wireless data demands.” AT&T joined the group last month.
For its part, Google in August asked the FCC for permission to conduct experiments in the 3.5 GHz band in up to 24 U.S. areas, including San Francisco, Boulder, Colorado, and Provo, Utah.
The FCC is currently evaluating releasing up to 11 GHz of high-frequency spectrum for mobile and fixed wireless broadband, including 5G. The bands include the 28 GHz (27.5-28.35 GHz), 37 GHz (37-38.6 GHz) and 39 GHz (38.6-40 GHz) bands, and a new unlicensed band at 64-71 GHz.
Already Google is urging the FCC to implement a sharing model in the 24 GHz band similar to the one the agency implemented in the 3.5 GHz band.
Here are select slides from Marshall’s presentation: