The FCC is working under a Congressional deadline of February 17, 2010 to develop a National Broadband Plan. That work includes looking for additional spectrum for wireless broadband services.
On December 2, 2009, the FCC issued a Public Notice asking for more comment on spectrum licensed to broadcast TV stations, and on market-based mechanisms that would encourage broadcasters to make spectrum available for wireless.
TV broadcasters generally like their spectrum as it is. They argue that over-the-air TV is a public service. It is the only source of video programming for some. A large investment was made in the recent DTV transition. They are working on advanced technologies including Mobile DTV and other content delivery platforms. Multicasting provides greater choice in programming without the need to subscribe to a cable or satellite service.
Some broadcasters question the notion of a spectrum shortage for wireless broadband. MSTV and NAB, in a proposed framework accompanying their comments, find fault in analyses showing a need of hundreds of additional megahertz. Technologies such as femtocells, they say, can increase wireless system capacity. To the extent that more spectrum is needed, they want the FCC to conduct a comprehensive inventory of all spectrum users.
Several lesser-known companies propose new technologies for broadcasters. Adaptrum, a startup developing cognitive radio technology for white space, proposes allowing TV stations to deploy broadband services within their coverage contours. CTB proposes a distributed, cellular architecture for broadcasters that would allow them to provide both broadcast and two-way broadband services. Sezmi has a system in which popular video programming is delivered via broadcast, and the remaining programming is delivered via broadband.
Many wireless proponents acknowledge broadcasters’ public service but encourage the FCC to look at repacking the spectrum such that wireless services get more spectrum while broadcasters’ audiences continue to be served. Motorola, CTIA, and CEA suggest distributed antenna systems, also known as Single Frequency Networks (SFNs). Multiple antennas transmitting at lower power would reduce interference, reduce the frequency separation required between stations, and allow TV stations to be repacked into a smaller portion of the spectrum. CTIA and CEA estimate that 100-180 MHz of spectrum might be made available for mobile broadband. An advantage of this approach is that today’s TVs are not made obsolete, and the current 19.4 Mbps digital data stream is still available to stations. Presumably, those benefiting from this new scheme would help pay the broadcaster’s transition costs.
Professor and former FCC Chief Economist Thomas Hazlett draws on his previous writings to propose an overlay auction of the TV band. In his plan, the 294 MHz DTV band is divided into seven national overlay licenses, each 42 MHz wide. These licenses are sold at auction. Those auction winners have exclusive, flexible-use rights. Existing TV stations are grandfathered and protected. The overlay licensee, however, can negotiate with the TV station and pay it to modify its operation or even agree to go off the air. It is estimated that the broadcaster’s use of spectrum is worth two or three orders of magnitude less than the same spectrum deployed for more-flexible wireless purposes.
The emerging white-space ecosystem is at risk in some of these plans. Any scheme that repacks the broadcast spectrum more efficiently, such as SFN, reduces white space. Google, Dell, and Microsoft – all supporters of unlicensed white-space services – are concerned about this.
Several dozen sets of comments were received in response to the December 2 Notice. It is likely the FCC will not decide all these issues related to TV spectrum by its February 17 deadline, and will them further, perhaps in a rulemaking proceeding.