The FCC will move ahead with a plan to make available 100 megahertz of shared spectrum in the 3.5 GHz Band (3550-3650 MHz) for the use of small cell and database technologies.

The Commission said the proposal lays the groundwork for the widespread deployment of small cell technologies across the spectrum and would spur significant innovation in wireless technologies and applications throughout the economy, while protecting incumbent users in the band.

The Notice of Proposed Rulemaking (NPRM) put forth comes at the behest of the President’s Council of Advisors on Science and Technology (PCAST), which issued a report this summer recommending spectrum sharing and small cell use in the 3.5 GHz Band.

The proposal envisions three tiers of users, each with different levels of rights and protections in the 3.5 GHz Band. The first tier, Incumbent Access, would include authorized federal users and grandfathered fixed satellite service licensees. These incumbents would be afforded protection from all other users in the 3.5 GHz Band. The second tier, Protected Access, would include critical-use facilities, such as hospitals, utilities, government facilities and public safety entities that would be afforded quality-assured access to a portion of the 3.5 GHz Band in certain designated locations. The third tier, General Authorized Access, would include all other users, including the general public, that would have the ability to operate in the 3.5 GHz Band subject to protections for Incumbent Access and Protected Access users.

The Commission said the spectrum access system, incorporating a geolocation-enabled dynamic database, would govern access to the 3.5 GHz Band.

In comments made before the subcommittee on communications and technology, Commissioner Ajit Pai expressed reservations about how the Commission is proceeding with the incentive auctions.

“The only closing condition set forth in the NPRM is that the revenues from the forward auction must cover the costs of the reverse auction,” Pai said. “I do not believe that this closing condition is sufficient, since it is essentially like ending a traditional auction as soon as the reserve price is met.”

Pai argued that if the Commission starts picking and choosing who may participate in the forward auction, such as by setting a spectrum cap or narrowing the spectrum screen despite the robust competition in the wireless market, it will result in “less participation, less revenue, less spectrum available for mobile broadband and less funding for public safety.”

Pai went on to stress the importance of generating revenue from the auctions, as the money will go toward constructing an interoperable public safety network, a project that has been discussed for more than a decade now.

Among other concerns, Pai also expressed wariness about spectrum sharing, as opposed to clearing, saying the PCAST report indicates some have “given up on clearing spectrum, especially in the federally owned AWS-1 band (1755-1780 MHz), in favor of auctioning off ‘shared rights.’”

“I’m not opposed to spectrum sharing,” Pai said. “For example, geographic sharing by creating exclusion zones around certain areas can be a useful tool. And spectrum sharing may be a workable alternative when auctions can’t be used to raise funds for relocation, such as in higher bands like the 5 GHz Band. But if our goal is to incentivize investment in wireless networks, nothing beats clearing.”

During a keynote at CTIA’s MobileCon back in October, Robert Wheeler, the Air Force’s chief information officer, addressed the idea of reallocating government spectrum, saying it could be a long and difficult task.

Wheeler said it isn’t possible to change equipment on satellites in orbit, so switching them about will take about a decade, “and that isn’t fast enough for industry,” he said.

The Air Combat Training System has been deployed in the 1755-1780 MHz band and illustrates the difficulty of moving government users to new bands. The system is critical to giving the military an edge during combat missions – Wheeler described it as “the ability for us to do ‘Top Gun’ on steroids” – and is used for more than 10,000 training flights each month.

The problem is that it’s “smack dab in the middle of that particular band, and moving that will take years,” Wheeler said. “It could have a disastrous impact to our nation if we get this wrong.”

Still, the NPRM put forth yesterday was met with praise by a number of industry groups, including the Wireless Innovation Alliance and the Telecommunications Industry Association, among others.

CTIA’s vice president of government affairs, Jot Carpenter, issued a statement saying the Wireless Association was pleased to hear of bipartisan support for moving ahead with implementation of the incentive auction process and for the focus in that process to be on maximizing the opportunity to bring new licensed spectrum to market.

“We look forward to working with the subcommittee’s members and the FCC to ensure that the incentive auction process produces a meaningful down payment toward meeting the mobile industry’s need for additional spectrum,” Carpenter said.