Late last year, a study commissioned by CTIA basically called Citizens Broadband Radio Service (CBRS) a failure, in part due to its low power levels and limited use cases.

Some saw it as a smear campaign against CBRS because CTIA would prefer the 3.1-3.45 GHz band to be licensed rather than end up looking more like CBRS, which involves a three-tiered sharing system to protect Department of Defense (DoD) incumbents.

Federated Wireless at that time defended CBRS and its role as an Innovation Band. But what does Federated Wireless CEO Iyad Tarazi say of those criticisms?

Tarazi was one of the early advocates for getting the CBRS band where it is today. Federated Wireless is a Spectrum Access System (SAS) administrator and built a coast-to-coast Environmental Sensing Capability (ESC) network that is designed to protect incumbent DoD users while allowing commercial operations to use the 3.5 GHz spectrum.

“I personally think CBRS is one of the cleanest and most interference-free spectrum [bands] out there because of all the automation and because of all the data we collect,” he said. “It’s almost astonishing, but we’re close to almost 400,000 radios on this system now. We get less than maybe 20 interference investigation requests a year and we handle all of them.”

Tarazi, whose career includes stints leading network engineering teams at Sprint and Nextel, said that when working at a carrier in the past, he would get many more interference requests, all from his team in the field, and it would take much longer to resolve them. Now when Federated gets an interference request, they’re able to find out where it’s coming from much faster and get a resolution pretty quick.

“Probably the biggest interference issue right now that we’re all dealing with is how do we continue to maintain this pristine and superior quality as we continue to add more to the system,” he said. “Growth is unrelenting,” which is why Federated created a set of products designed to operate in the more demanding environment.

DoD at the center of it all

The best proof points for CBRS are all the DoD deployments that are using General Authorized Access (GAA), the unlicensed portion of the CBRS band, and it works for them, he said. “If we can optimize GAA for a DoD deployment that’s very demanding, you know we can do it.”

The DoD is Federated Wireless’ biggest customer on the private wireless side of its business. On the spectrum management side, the top two are Verizon and the multitudes of fixed wireless partners that it works with primarily through Cambium Networks.

Federated announced in May 2019 that it had completed its ESC network, which he views as the best mark for a commercial launch date, meaning it has been only about four or so years since CBRS kicked off, although it was in development much longer than that.

Interestingly, Federated is working on an Automated Frequency Coordination (AFC) model for the 3.1-3.45 GHz band, which is being studied from a public policy perspective and one where there’s been a strong desire from some corners for a shared spectrum structure. Its current occupant is the DoD.   

He said that stakeholders likely will turn to CBRS for a lot of learnings, adding to them and expanding the user base, but that’s probably three to four years away from any sort of commercialization.