The FCC is looking for more spectrum for wireless broadband, and the spectrum currently used for TV broadcasting has emerged as a prime candidate. This week the commission gave broadcasters until Dec. 21 to justify the use of their existing spectrum.
In Public Notice (DA 09-2518): Data Sought on Uses of Spectrum [PDF] the FCC asked broadcasters to comment on "the impact to the economy if insufficient additional spectrum were made available for wireless broadband deployment, in terms of investments, jobs, consumer welfare, innovation and other indicators of global leadership."
Additionally it seeks comment on the impact to the country's economy and public welfare should off-air television coverage be cut to accommodate a repacking of stations as part of a spectrum recovery program.
Reducing coverage and repacking indicates the FCC may be considering reducing broadcast stations' coverage area to allow reuse of their channels at shorter distances. This could open up some additional channels, but from my experience, stations are already closely packed in some congested areas. In the northeast, for example, WCBS-TV in New York City and WFSB in Hartford share channel 33. WCAU in Philadelphia and WPXW-TV in the Washington D.C. suburb of Manassas, Va. share channel 34.
Under the heading "Potential Approaches to Increase Spectrum Availability and Efficiency" the Public Notice states, "There may be opportunities for broadcasters to share 6 MHz channels in a market without significantly disrupting the free over-the-air television service that consumers enjoy today."
The FCC recognizes this sharing would affect the "number and type [of] signals that each [station] can broadcast."
Some stations are transmitting two HDTV programs in the 19.39 Mbps available in one 6 MHz channel, but quality will suffer if the channels are transmitting material that's noisy, has a lot of action or is otherwise difficult to compress. While this sharing may be attractive to some stations, especially if they aren't broadcasting high definition, I'd hate to see it reduce the number of HDTV slots available for the variety of ethnic multicast channels available in markets such as Los Angeles, or the interesting and educational multicast programs available on many public TV stations.
Other suggestions to free up bandwidth for broadband include "greater collocation of transmission facilities closer to the center of densely populated areas;" improvements in MPEG-2 technology which would allow more programs in one 6 MHz channel; and spectrum efficiency gained by "deployment of next generation technologies over that currently achieved under the ATSC standard."
The FCC asks what would be required for broadcasters and consumers to transition to more advanced technologies, and how difficult would it be for them to make the transition, and also poses the question, "What would be the costs to replace off-air delivery to MVPDs and consumers with other means (fiber, microwave)?"
Receiver and antenna limitations influence channel allocations and power levels. The FCC recognized this and asks, "To what extent would establishing antenna and receiver standards facilitate spectral efficiency and improved reception in broadcasting?"
The FCC also requested comments on "What innovations in applications, services, or business models will create synergies between broadband and broadcast services, or other new value from currently licensed spectrum?"
One of the obvious innovations is mobile DTV. Streaming video and audio over the Internet individually to each viewer and listener requires a lot of bandwidth. The iPhone has had a significant impact on AT&T's network. Mobile DTV broadcasting has the advantage of using the same amount of bandwidth to reach thousands of viewers as one viewer requires streaming over the Internet.
The Public Notice challenges TV broadcasters to justify their use of the spectrum with questions such as "How do broadcasters use the capabilities of digital television today?" It seeks specific answers, including "data rate allocations to HD, SD, multicast streams, bandwidth leasing arrangements, etc. and the business rationale behind these choices."
The Commission also wants to know how broadcasters plan to use licensed spectrum in the future and how they should "evaluate the future economic value of off-air digital television and new capabilities to offer mobile DTV broadcasting."
It has been reported that Blair Levin, the person leading the search for more broadband spectrum, is talking not only to broadcasters but to their investors as well. It isn't surprising that the Public Notice asks, "How does the financial community in general view that future value?"
While the Public Notice makes it clear broadcasters have to justify the spectrum they have and suggest ways to improve efficiency in their use of it, the FCC also recognizes the value of broadcasting and asks for suggestions on how it can help broadcasters. For example, in reference to the migration of viewers from mass-market "appointment" viewing to more fragmented and time-shifted viewing, the FCC asked what it can do to help broadcasters "participate in this evolution?" This might be a reference to one suggestion that would give broadcasters bandwidth on wireless broadband channels.
In a proceeding that could have such a major impact on broadcasting in the United States and the relatively small in percentage—but large, in total number of off-air TV viewers—it's amazing the FCC is allowing only 19 days for comments.
Given the power and influence of the wireless companies that want this spectrum for their businesses, it is difficult to imagine broadcasters will make it through 2010 without some change in their channel allotments. While it will take some time to work out the details, the big question is whether these will be voluntary changes, such as broadcasters giving up spectrum for cable carriage rights, shared bandwidth on another channel and some financial compensation. Or would there be a ruling that essentially forced broadcasters off-air by some mechanism such as excessive spectrum fees in order to free up spectrum for the cell phone companies?
My worst fear is the FCC might allocate all of the UHF TV spectrum to the cell phone companies, requiring TV broadcasters to squeeze into channels 2-13, and limit broadcast content available to viewers by putting multiple stations on one channel when they run out of space in major markets such as New York, Washington D.C. and Los Angeles. Rural viewers, of course, would be out of luck due to interference zones between television markets when such a small number of channels were used. In any event, it seems likely that some, and perhaps many, broadcasters would have to move to another channel.
I'm hoping that unlike the original transition, which gave back 108 MHz of spectrum, broadcasters will not have to bear the entire cost of the channel changes needed to free up even more spectrum for auctioning to wireless providers.
Doug Lung is one of America's foremost authorities on broadcast RF technology. He has been with NBC since 1985 and is currently vice president of broadcast technology for NBC/Telemundo stations.
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