One of the items on the agenda for the Nov. 30 FCC Open Meeting includes a notice of proposed rulemaking seeking comments on rules that would facilitate the most efficient use of the UHF and VHF TV bands.
The commission says that the proposals are "an important step toward the agency's spectrum goals as outlined in the National Broadband Plan," and they would eliminate several obstacles to establishment of mobile broadband service in spectrum currently reserved for TV broadcasters. This usage would be made possible through "innovations such as channel sharing and generating increased value within the VHF band."
I've previously discussed the National Broadband Plan (NBP) and its recommendation that 120 MHz—almost half of the usable TV spectrum—be reallocated from broadcast television service (and white space devices) to wireless broadband. The FCC and the Obama administration have said repeatedly that any relinquishment of spectrum, either through channel sharing or giving up off-air broadcasting completely, would be voluntary. However, there are four things that should be looked for in the Nov. 30th NPRM, in order to understand the real impact of the proposed rules on TV broadcasting.
- •Will stations that voluntarily decide not to give up their spectrum be able to stay on their existing channels? For example, WRC-TV, the NBC O&O in Washington DC, is unlikely to give up its spectrum or share a channel, as it's already broadcasting HD, two multicast channels, and Mobile DTV, thus fully occupying the Channel 48 allocation it was given. The CBS O&O in Los Angeles is on Channel 43. The wireless companies want contiguous spectrum. If the FCC follows the same plan as when reallocating channels 70-83 for cellular and SMR and, just last year, channels 52-69, stations in the upper UHF spectrum have reason to worry. This leads to the next question....
- •If the FCC reallocates a contiguous block of spectrum starting at Channel 51—and working down—what happens to the stations on the upper UHF channels? One hint is the agenda note about making VHF spectrum more valuable for broadcasting. Unfortunately, for Mobile DTV (perhaps the most promising and highest value use of spectrum for broadcasting), VHF doesn't work very well. Even the high-band VHF channels have problems getting a signal to handheld devices due to a huge disadvantage in antenna efficiency. Granting a 10 dB boost in effective radiated power will help, but is unlikely to fully offset the loss in antenna efficiency and the high level of electrical noise at VHF. Further, generating this much power at VHF will be difficult due to the size of the transmitting antenna. A VHF antenna with the same gain as a UHF antenna would need to be about four times larger. In most cases, this is not physically possible. Will a UHF station with excellent coverage be forced to take a VHF channel with little indoor—and practically no—handheld DTV coverage?
- •Who pays? Repacking spectrum means moving stations to different channels and possibly different sites. For most stations, changing channels will mean installing at least one new transmission facility in order to avoid interrupting programming. In the event there isn't sufficient space on an existing tower, both an interim and a final facility would need to be constructed. Costs are likely to be close to, or even exceeding, $2 million per station. Will the wireless companies pay for these moves or will broadcasters be forced to pay the cost themselves in order to voluntarily retain their spectrum?
- •What happens if there isn't enough TV spectrum for both the broadcasters who don't voluntarily give up their spectrum and the 120 MHz the FCC wants to give to the wireless companies? Will the Commission accept less than 120 MHz in those markets where there isn't enough spectrum, even if all the stations share channels? Will stations have to compete for the few remaining channels? Who gets stuck on VHF? What happens to the losers?
Remember that the Nov. 30 document will be a Notice of Proposed Rulemaking, not the final law. Congress must pass a law allowing the FCC to carry out its "incentive auction" plan.
Will the Obama administration be able get the Republican House of Representatives to agree to it?
The NBP implies a 2013 date for freeing up this spectrum. I would be surprised if Congressional approval is received and final rules issued before the end of 2011. Considering the amount of time it took the FCC and broadcasters to complete the DTV transition—which involved adding a new service rather than moving an existing one—two years for such a drastic change seems unrealistic unless broadcasters who want to retain their spectrum are able to do so on their existing channels. If the wireless companies and other NBP proponents want fast access to TV spectrum—as I see it—they will have to accept the reality that the spectrum they receive may not be contiguous. Some of it might even be below 300 MHz.
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Doug Lung is one of America's foremost authorities on broadcast RF technology. As vice president of Broadcast Technology for NBCUniversal Local, H. Douglas Lung leads NBC and Telemundo-owned stations’ RF and transmission affairs, including microwave, radars, satellite uplinks, and FCC technical filings. Beginning his career in 1976 at KSCI in Los Angeles, Lung has nearly 50 years of experience in broadcast television engineering. Beginning in 1985, he led the engineering department for what was to become the Telemundo network and station group, assisting in the design, construction and installation of the company’s broadcast and cable facilities. Other projects include work on the launch of Hawaii’s first UHF TV station, the rollout and testing of the ATSC mobile-handheld standard, and software development related to the incentive auction TV spectrum repack.
A longtime columnist for TV Technology, Doug is also a regular contributor to IEEE Broadcast Technology. He is the recipient of the 2023 NAB Television Engineering Award. He also received a Tech Leadership Award from TV Tech publisher Future plc in 2021 and is a member of the IEEE Broadcast Technology Society and the Society of Broadcast Engineers.