Millions of dollars have reportedly already been poured into developing technology for the Citizens Broadband Radio Service (CBRS), but CBRS Alliance member T-Mobile warned the device ecosystem for the band won’t flourish without significant and sustained operator investment. And that, the Un-carrier said, won’t come without the certainty of longer, larger licenses and priority access across the board.

In a filing with the FCC last week, T-Mobile lobbied the Federal Communications Commission to rethink its approach to the band. Specifically, the Un-carrier asked the FCC to initiate immediate action to change the CBRS licensing scheme to use Partial Economic Areas rather than Census blocks to measure licenses, extend the license terms to 10 years, and make all priority access licenses (PAL) available at auction, regardless of the number of applications received for each. While this sounds similar to a proposal recently floated by industry association CTIA, T-Mobile went a step further, asking the Commission to make all 150 MHz of spectrum in each market open to priority access licensing rather than maintaining the current limit of 70 MHz of PAL per market.

The Un-carrier argued these changes are necessary to keep the United States at the forefront of 5G developments, and bring it in line with global band selections for next generation services. Without these changes, T-Mobile wrote, there will be little incentive for operators to invest in the band.

“While making the 3.5 GHz band available on a licensed-by-rule basis will be an important component of 3.5 GHz band use, the viability of the device ecosystem for the band will depend on licensee investment. That investment will be limited unless the Commission maximizes the use of the band for licensed 5G operations,” T-Mobile wrote. “The Commission’s rules, however, currently limit PALs to 70 megahertz per market – a structure that will likely only support a single licensed provider offering 5G in each market and will, as a result, limit incentives to invest and inhibit technological growth. In order to optimize the 3.5 GHz band for 5G, there must be an opportunity for multiple carriers to aggregate larger bandwidths.”

But T-Mobile’s viewpoint is unlikely to be shared by advocacy groups like New America’s Open Technology Institute; Next Century Cities; Center for Rural Strategies; the American Library Association; the Schools, Health, and Libraries Broadband Coalition; and Public Knowledge, which contested CTIA’s earlier proposal as an “effort to backtrack on this unique achievement in forward-thinking spectrum policy.”

Those groups pointed out the use of large license areas would be inefficient for indoor use cases, as well as small-cell, high-capacity use cases. Large licenses would also likely leave spectrum unused in low-density environments outside traffic centers, whereas the current model would allow open access for both operators and end users, the coalition said.

Baicells Technologies North America President Patrick Leary also recently noted changes to the CBRS licensing scheme have the potential to “price out millions of others who want and need the ability to build private networks.” Those entities include utilities, municipalities, and schools, among others, he said.

“If that happens, they will be forced to pay large sums to use (carrier) services, or once again be relegated to the spectrum desert where their only other choice is a very crowded WiFi, where their critical networks will struggle against the interference crush of garage door openers, baby monitors, smart TVs, and the countless WiFi devices,” Leary wrote.