The FCC approved rules for next year's incentive auction of 600 MHz broadcast TV spectrum that will open up bandwidth for unlicensed wireless use. Depending upon how much spectrum is voluntarily relinquished by broadcasters in a reverse auction and repacked for the forward auction, a total of 14 to 28 MHz of guard band spectrum should be available for unlicensed use in a given area. An FCC official said that, depending on how much spectrum is repurposed in a given market, the agency expects the guard bands to be between 7 MHz and 11 MHz wide.
The forward and reverse auctions will be implemented in a series of stages, with each stage aimed at a specific clearing target. The commission adopted Partial Economic Areas (PEAs) as the service area for the 600 MHz Band.
Advocates of unleashing more unlicensed spectrum welcomed the commission's plan, which passed on a 3-2 vote along party lines, with Democrats in the majority.
Because much of the spectrum that might be opened for unlicensed use would sit in vacant spaces between TV and broadband services, it would have to be managed in the same manner as current TV white space (TVWS) spectrum, whose rules require devices to contact an authorized TVWS database and ensure channel availability and other operating parameters so they will not interfere with TV broadcast operations.
Google (NASDAQ: GOOG), which operates a spectrum database to support the use of TV white space (TVWS) spectrum that was liberated for unlicensed use via the 700 MHz auction, said it will work to ensure its database also enables sharing in the newly allocated spectrum. In March, Google lobbied the commission to open four 6 MHz-wide channels in the 600 MHz band on a nationwide basis, a wish that was not granted. On April 30, a representative for Google, Broadcom and Microsoft (NASDAQ: MSFT) presented a modified plan to the FCC.
Commenting on the FCC's newly passed 600 MHz band plan, Aparna Sridhar, Google policy counsel, wrote in a blog post, "While the plan doesn't provide as much unlicensed spectrum as we recommended, it should provide just enough unlicensed spectrum to attract investments in equipment and operations in the new band."
"We applaud the commissioners for adopting an incentive auction band plan that facilitates both licensed and unlicensed broadband services, including a win-win solution that accommodates both wireless microphones and unlicensed innovation," said Michael Calabrese, director of the Wireless Future Project at the New America Foundation.
The Wireless Innovation Alliance--whose membership includes Google, New America Foundation, Microsoft and others--said the FCC's blueprint "offers the potential for allocating a baseline amount of spectrum necessary to ensure a way forward for TV white spaces, Wi-Fi and the myriad of unlicensed applications that will meet our nation's growing wireless needs."
The commission's Report and Order lays out a 600 MHz band plan consisting of 5 MHz, paired uplink and downlink bands, with the uplink portion starting at channel 51 (698 MHz) and expanding downward. The plan also includes "technically reasonable" guard bands--including a uniform duplex gap of 11 MHz to separate uplink and downlink spectrum--which can be used for unlicensed services nationwide. Wireless microphones used by broadcasters and cable programming entities will be licensed to operate on a portion of the duplex gap. Other wireless mics can operate unlicensed in the guard bands.
In addition, unlicensed devices will be able to use 6 MHz at channel 37 in locations where the channel is not already in use, "subject to the development of technical rules to prevent harmful interference" to the incumbent Wireless Medical Telemetry Service and Radio Astronomy Service, the commission said.
The FCC said it expects there will be at least one channel not assigned to a TV station in all areas at the end of the repacking process, and this "naturally occurring" TV white-space channel will be allocated for shared use by unlicensed devices as well as wireless microphones. Further, any other unused TV channels following the incentive auction will be available for unlicensed devices as well as wireless microphone use.
Advocacy group WiFiForward--whose membership also includes Google as well as Comcast (NASDAQ: CMCSA), Time Warner Cable (NYSE: TWC) and others--said that by ensuring unlicensed availability of at least three channels in every community in the nation, "the FCC has laid the foundation for the investment and innovation needed to develop a new class of 600 MHz unlicensed technologies."
FCC Commissioner Jessica Rosenworcel, who has championed unlicensed spectrum, commented that the FCC found "creative ways" to strike a between licensed and unlicensed spectrum. "This creativity started with ditching the tired notion that we face a choice between licensed and unlicensed spectrum. This is a simplistic relic from the past that we should have long since retired--because good spectrum policy requires both," she said.
However, there is still work to be done to open up chunks of the 600 MHz band for unlicensed use. Going forward, the FCC must initiate a rulemaking proceeding to consider changes to its existing Part 15 rules that will facilitate unlicensed use of the television bands, 600 MHz guard bands and channel 37.
The FCC will require repurposed spectrum be cleared no later than 39 months after the repacking process becomes effective. New licensees will be required to build out to 40 percent of the population in their service areas within six years and to 75 percent of the population by the end of their initial license terms of 12 years.
The National Association of Broadcasters was quite unhappy with the auction plan. Among other things, the NAB said the commission's decision to use untested coverage and interference software potentially jeopardizes hundreds of TV stations and millions of over-the-air TV viewers.
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