Ericsson: CBA plan poses ‘detrimental impact’ on 5G ecosystem

Ericsson said it's committed to developing products for 5G in midband spectrum, but it's not in favor of a two-tranche approach as described by the C-Band Alliance. (FierceWireless)

Ericsson warned the Federal Communications Commission that if it adopts a two-tranche approach promoted by the C-Band Alliance (CBA), it would have a “detrimental impact” on the development of a 5G ecosystem in the 3.7GHz-4.2GHz band.

The CBA’s proposed plan, described in an April 9 filing (PDF) with the FCC, involves spectrum being cleared and released in two tranches. The first tranche would provide market access to 60 MHz of spectrum available in 46 top markets. This would be done within an 18-month period after the adoption of an FCC order approving the CBA plan.

The second tranche, as Ericsson explained, expands the available spectrum in the top 46 markets with an additional 120 MHz of spectrum, giving the 46 top markets access to a total of 180 MHz. In other partial economic areas (PEAs), a total of 180 MHz would be cleared and made available for 5G. The second tranche would be available 18 months after the first one.

“Although the CBA plan is an attempt to respond to the need for a serious dearth of licensed mid-band spectrum, implementing a plan that clears and makes spectrum available only in certain markets and is delivered in multiple swaths may not improve the timeline for when mid-band spectrum can be deployed,” Ericsson told the commission in its April 26 filing (PDF).

“Most importantly, it is questionable whether co-channel concerns can be addressed given the CBA Transition proposal,” the Swedish vendor said. “From a 5G ecosystem perspective, products designed and delivered to support the first tranche must be replaced when the second tranche of spectrum is delivered to support the new passband. Costly development of an interim solution could have a detrimental impact on the timing and availability of 5G products to support the first tranche.”

RELATED: T-Mobile’s revised plan for C-Band a ‘fatally flawed’ gambit: CBA

This isn’t the first time Ericsson has blasted the CBA’s plan, but it is its first filing since the CBA released more details about the transition, in what it describes as the “Transition Implementation Process.” Last year, Ericsson pointed out (PDF) that the CBA proposal of 180 megahertz for flexible use spectrum (i.e., 200 megahertz, less a 20 megahertz guard band) was far less than what's necessary to sustain a robust 5G service.

Ericsson also said the FCC must consider the implication of releasing spectrum in multiple tranches. “The industry has expectations for allocations of the order of 100 MHz per operator in the C-band,” the company said. “When spectrum is released piecemeal, the consequence is fragmentation of the band, and possible segmentation of the 5G bands in devices; factors which will severely affect the commercial success of the band.”

RELATED: O’Rielly: ‘No more dawdling’ on efforts to procure C-band spectrum

While Ericsson is not alone in its critique of the CBA’s proposal, FCC Commissioner Michael O’Rielly last week suggested it’s better to get some of this spectrum allocated for 5G sooner rather than later.  

“We must be willing to adopt a plan that gets midband spectrum into providers’ hands as soon as possible with the appropriate protections,” he said during an appearance at the Brooklyn 5G Summit, and to do this, the commission needs to finalize its review and wrap up the C-band proceeding in the next few months.