The FCC on Friday approved a plan that will allow broadband providers and other companies to use and share spectrum that until now has been held mostly by the United States military. "Since they don’t make spectrum anymore, and since spectrum is the pathway of the 21st century, we have to figure out how we’re going to live with a fixed amount," said FCC Chairman Tom Wheeler said during Friday's session. "Sharing is key to that." The Citizens Broadband Radio Service (CBRS) plan — yes, that's a mouthful — will open frequencies from 3550MHz to 3700MHz to commercial companies; right now, they're mostly being used by radar systems belonging to the US Army and Navy.
These airwaves don't travel very fall or provide strong wall penetration, and it'll likely be years before your smartphone can harness them. But eventually, they could be used to bolster small cell deployments, LTE hotspots, and other applications that companies haven't figured out yet. Wheeler spoke of the benefits of the FCC's "historic" shared approach last month in a blog post. At that time, he said:
The 3.5 GHz band is an innovation band. As a result of technological innovations and new focus on spectrum sharing, we can combine it with adjacent spectrum to create a 150 megahertz contiguous band previously unavailable for commercial uses. It provides an opportunity to try new innovations in spectrum licensing and access schemes to meet the needs of a multiplicity of users, simultaneously. And, crucially, we can do all of this in a way that does not harm important federal missions.
The military won't have to worry about interference
So how does the FCC intend to prevent interference in those frequencies? It's got a plan. The proposal calls for a three-tiered system; at the top is the federal government along with other users already running satellite and radar services on the 3.5GHz band. They're guaranteed protection from interference caused by those operating in the lower two tiers. (The Defense Department can also establish exclusion zones around the coasts where commercial users aren't allowed.) One step below that, the FCC will auction off short-duration licenses that are also shielded from interference from the lowest tier, which is called the General Authorized Access tier. This is most similar to unlicensed spectrum in that any company with an FCC-certified device won't need additional approval from the commission to start using the shared spectrum.
Nothing's happening yet, though; in approving the proposal, the FCC also said it will open up another public comment period to address the many complexities of shared spectrum. But tech companies and the FCC's own commissioners are excited. "This is big," said Commissioner Jessica Rosenworcel, describing the FCC's move as "a paradigm shift that paves the way for new services, new technologies, and more mobile broadband."