U.S. RF Spectrum Policy Under Fire

The Aspen Institute Communications and Society Program released its report on its June 2004 annual Conference on Telecommunications Policy, titled Challenging the Theology of Spectrum - Policy Reformation Ahead. The report asserts that the idea of "frequencies" as the defining units of spectrum needs to be changed to recognize that new technology allows emissions to share the same frequencies through the technologies such as CDMA--code division multiplexing, cognitive radios that can adapt their use of frequencies or codes in real time in response to the needs of other uses, and interference temperature.

The report said that change might not come easily. "Many of the technologies are unproven in the field, and wholesale abandonment of the current policy regime therefore is not in order; instead, the idea of letting a thousand flowers of experimentation bloom or at least a bouquet or two seemed to capture the group's mood."

The participants included experts from government, investment firms, education, and the broadcast and communications industry, including Edmond Thomas, FCC Chief Engineer, Robert Pepper, Chief of Policy Development at the FCC, Preston Padden from Walt Disney/ABC, Marsha MacBride from the NAB, and Michael Gallagher with the National Telecommunications and Information Administration. See Challenging the Theology of Spectrum - Policy Reformation Ahead for the complete list of the 27 participants.

Broadcasters received much attention. The report indicates this may have been "because they occupy such large swaths of the most valuable spectrum and do so under policies worked out more than 50 years ago, when technology was entirely analog and genuinely harmful interference was a serious problem."

While it isn't unusual for engineers to simplify explanations for non-technical audiences, I was surprised at some of the quotes attributed to FCC personnel at the conference. Ed Thomas, the FCC chief engineer, was quoted as saying, "Broadcasters want to exert rights over, say, channel 6 in New York City even though [as a white space buffer] nobody has a right to it on grounds it might interfere with 5 and 7. What really bothers me is, here's a group of incumbents trying to exercise rights even on spectrum they have no license for."

Although the interference between adjacent channels has been a problem for analog broadcasting, in many congested areas adjacent channels are already in use. In the Los Angeles area (including San Bernardino and Riverside), for example, there are TV stations on channels 28, 29, 30, 31, 32, 33 (LPTV), 34, 35 and 36. Channel 37 is reserved for radio astronomy, but channels 38, 39, 40, 41, 42, 43, and 44 are all currently allocated or in use.

The comments about incumbents trying to exercise rights on spectrum they have no license for doesn't seem to hold, at least in Los Angeles, the nation's second largest market. Broadcasters also opposed the use of channel 7 in a market where there is a channel 6 because of interference. Of course, channel 7 (174 MHz lower edge) is separated by 86 MHz from channel 6 (upper channel edge of 88 MHz) so there no chance of adjacent channel interference between these stations. However, interference is possible from the second harmonic of the channel 6 signal, which could be generated in the receiver front end in a strong signal environment, since FCC rules limits harmonic emissions from TV transmitters.

Robert Pepper, the FCC chief of policy development, said that TV channels occupy only 196 MHz of the TV spectrum in Los Angeles. Using the FCC database and counting stations in the DMA with coverage into Los Angeles, I see 42 6-MHz wide channels are in use by full power stations, totaling 252 MHz of spectrum. If LPTV stations are added, this increases to at least 282 MHz. If adjacent market channels such as those in Santa Barbara, Palm Springs and San Diego are included, the amount of spectrum "unused" is even less, even without including UHF TV channels already allocated for public safety and other two-way radio use.

Of course, when analog broadcasting ends, almost half of this spectrum--LPTV stations don't have two channels--will be returned, although stations on channels 52-69 will have to find new channels between 2 and 51, excluding channel 37 and the low UHF channels already allocated for other services.

Marsha McBride, from NAB, explained broadcasters point of view by saying that broadcasters aren't going away any time soon and because they are local, they are more connected to their communities than cable. She recommended policymakers engage the industry cooperatively rather than try to force mandates on broadcasters.

The report's topics are organized by "old assumption/new perspective." One of the "old assumptions" that affects broadcasters is "The public's investment in consumer premises equipment (CPE) needs to be protected, and any attempt to reduce the value of CPE may create massive political backlash." The "new perspective" is "Public fears can be handled readily by using a small fraction of the efficiency gains from policy change for subsidies.

Walt Disney Company's Preston Padden said people still watch analog TV sets and will "give them up with the greatest reluctance. "The U.S. Congress knows there are no votes to be had in turning off people's television sets. Years ago, when just 200,000 rural satellite dish owners got upset with a policy change, they tied Congress into knots." The counter argument is that new efficiency gains from totally clearing broadcast spectrum would cover the cost of installing cable to subscribers' extra televisions and making free basic digital cable or satellite service available to non-subscribers.

Not all new perspectives are as controversial as the fate of broadcast spectrum. For example, one "Old assumption" is "Transmitter technology is more important and more important to regulate than receiver technology." The "New perspective" on this is "Receivers are more important, and setting standards and regulating receivers may be the proper emphasis." For the "interference temperature" approach to have a chance of working, receiver performance in the presence of other signals has to be well defined.

See the report for details on this and other discussions at the Conference. Challenging the Theology of Spectrum - Policy Reformation Ahead is a summary of comments from the top decision makers and policy setters in the communications and spectrum manager. Therefore, it is likely we will see these proposals being pushed in Congress and at the FCC.

Other commentators are echoing these new perspectives. See America Needs Unchained Spectrum by Gregg Blonder in Business Week's online edition.