Hoping to jumpstart a U.S.-led spectrum-sharing and small cell revolution, the FCC moved to open up the 3.5 GHz band for use by entities deploying small cells, which will share the spectrum with incumbents.
The commission issued a Notice of Proposed Rulemaking (NPRM) that, among other things, will allow small cell devices to deliver wireless broadband service in the 3550-3650 MHz band via a shared-access scheme.The band is currently used for U.S. Navy radar operations and covers 60 percent of the U.S. population.
The proposed 3.5 GHz Citizens Broadband Service will be covered by a three-tier authorization mechanism and managed by a geolocation-enabled dynamic spectrum access database that is modeled on the existing TV white spaces database. The three proposed tiers of operation are: incumbent access (federal and grandfathered licensed FSS 3.5 GHz Band users), priority access (hospitals, utilities and public-safety entities) and general authorized access (the general public).
"GAA users could include a wide range of residential, business, and others, including wireless telephone and Internet service providers," said the FCC.
The incumbent tier would be guaranteed protection from harmful interference caused by all other users in the band, while priority-access users would have a measure of interference protection in portions of the 3.5 GHz band at specific locations. The general public would be allowed access to the band on an "opportunistic basis" within designated geographic areas, but they would have to live with the interference caused by other users.
"Under our main proposal, users in the Priority Access and GAA tiers would be licensed by rule as Citizens Broadband Service users under Part 95 of the Commission's rules. A license-by-rule approach would provide individuals, organizations, and service providers with 'automatic' authorization to deploy small cell systems, in much the same way that our Part 15 unlicensed rules have allowed widespread deployment of Wi-Fi access points," said the FCC.
The draft NPRM also includes a supplemental proposal to expand the proposed licensing and authorization model to the 3650-3700 MHz band, which would be included in the Citizens Broadband Service licensing framework. Current users in that band would be reclassified as general authorized access users.
The FCC's plan for the Citizens Broadband Service reflects recommendations included in a report issued in July by the President's Council of Advisors on Policy and Technology (PCAST).
"This proceeding represents two distinct policy and technology innovations that have tremendous promise," said Chairman Julius Genachowski.
The first innovation is spectrum-sharing, which maximizes the use of spectrum, though Genachowski said the first choice is always to clear and reallocate government spectrum for commercial uses, but that is not always possible.
The second innovation is small cells. "It's a very important technology revolution, and one of the things that is exciting about his proceeding is that having a band that is essentially a small cell band may be more likely to drive innovation business models around small cells than otherwise," Genachowski said.
He added that the 3.5 GHz proceeding should ensure the United States gains global leadership in both spectrum sharing and small cell deployments. Regarding the former, "the U.S. will benefit if we are the country that sorts through all the challenges of that first because we know every country is looking at this," he said.
Genachowski said the U.S. also has a chance to lead the world in putting the 3.5 GHz spectrum to use. "This is spectrum that generally is available around the world, but with this proceeding, we are becoming the first country of scale to be moving forcefully to put this spectrum to work in the marketplace," he said.
Observers say the rulemaking proceeding is a crucial step in opening up spectrum for additional data capacity. "The 3550 MHz proceeding can produce a win-win outcome, where the Navy uses a portion of the total capacity of the band exclusively and unlicensed and lightly-licensed users use another portion on a low-power, small-cell basis that will protect existing military uses and thereby expand access to wireless broadband nationwide," said a statement from the Wireless Innovation Alliance, whose membership includes Google (NASDAQ:GOOG), Microsoft (NASDAQ:MSFT), Spectrum Bridge and Dell.
FCC Commissioner Ajit Pai said he is interested in examining whether 3.5 GHz exclusion zones can be kept small because 50-60 percent of the U.S. population will not be able to use the 3.5 GHz band under the proposed exclusion zones, which prohibit commercial use along coasts and near certain inland Department of Defense training sites.
"This is especially troubling because the substantial majority of the spectrum-limited markets [are] found within these zones, from New York to Los Angles and Seattle to Miami," said Pai.
He also said he hopes the commission will soon take action to exempt small cells from environmental processing requirements. "We shouldn't impede their deployment in the 3.5 GHz band or any other band with unnecessary red tape," said Pai.
Qualcomm applauded the FCC's move to open up the 3.5 GHz band. "Small cells, when deployed in conjunction with macro cells using smart network technology, will expand capacity substantially, enhance network coverage and reliability and even improve position location accuracy. Small cells will require a predictable quality of service, and, therefore, the spectrum must be shared on an authorized basis," said Dean Brenner, senior vice president of government affairs for Qualcomm (NASDAQ:QCOM).
Qualcomm is part of the High Tech Spectrum Coalition, which also includes Apple (NASDAQ:AAPL), Alcatel-Lucent (NASDAQ: ALU), Cisco, Ericsson (NASDAQ:ERIC), Intel, Nokia (NYSE:NOK), Research in Motion (NASDAQ:RIMM) and Samsung. The HTC sent a letter to top federal lawmakers this week in which it asked Congress to expand the upcoming incentive auction to include spectrum that can be reallocated from federal users for commercial uses. The group recommended that incentives could induce federal users to "become more efficient, share with one another, vacate or to lease their spectrum," according to The Hill.
The Wireless Internet Service Providers Association (WISPA) heralded the FCC's move on 3.5 GHz, which could provide additional spectrum to its members. "The proximity of this band makes it a natural extension to existing spectrum in the 3650-3700 MHz band. Wireless Internet service providers use this band every day to provide fixed broadband services to rural areas around the country. Access to an additional 100 megahertz of spectrum will vastly improve our members' ability to expand service to the millions of Americans who have little or no choice in broadband access," said Elizabeth Bowles, WISPA president.
Another band being eyed for sharing between government users and commercial interests is the 4.9 GHz band, which consists of a contiguous block of 50 MHz located at 4940-4990 MHz and is currently designated for public-safety fixed and mobile uses.
In addition, T-Mobile USA is involved in a joint industry-government effort to test spectrum sharing in the 1755-1780 MHz band, which the operator contends will open up the frequencies for pairing with the existing AWS-3 band for eventual auction, long before all government entities are cleared from the spectrum.
WISPA pushes testing to validate 4.9 GHz spectrum sharing
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3.5 GHz spectrum sharing effort could take years to produce results
T-Mobile: We'll prove shared 1755-1780 MHz band can be auctioned
Spalter: Spectrum sharing and the elusive silver bullet
AT&T raises red flag over shared spectrum plan
4.9 GHz band could open up for limited commercial use
Article updated Dec. 12, 2012, to include additional information from the FCC's Notice of Proposed Rulemaking and Order.