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| The Open Spectrum movement sees a future in which the community can directly access the airwaves, writes ELLIE RENNIE, and Dewayne Hendricks is showing how it can be done IN 2010, or thereabouts, the Australian government plans to switch-off analogue television transmitters. The electromagnetic spectrum, or radio waves, currently occupied by the free-to-air analogue channels will be vacated. You might call it an eviction, except that most of the current tenants (the commercial and national television broadcasters) have already been given the equivalent of rent-controlled penthouse suites on another band reserved for digital television. So what will happen to the old “analogue” spectrum? Will it be auctioned off to the highest bidder or left for media squatters to inhabit? The media experts have been assuming that the leftover channels will be used for new digital television services. But recent developments in the US and UK indicate that the vacant radio waves may be put to a different use altogether. Ofcom (the UK’s Office of Communications) is currently undertaking a “Licence-Exemption Framework Review” which proposes to set aside greater bandwidth for devices that can transmit information without needing permission from the regulator. In other words, we may see new portions of the airwaves turned into a public commons which anyone can use as long as they comply with some basic rules. “Licence exempt” does not mean that you can start transmitting a new London-wide television channel from a bedsit in Brixton – at least not in the near future. But it may pave the way for new communications technologies that will transform the communications landscape in ways that are perhaps even more radical. Licence exempt use of the airwaves already exists in Austalia, but only for very low power and short-range communication. Every time you turn on a baby monitor, connect to wireless broadband or operate your garage door you are participating in the spectrum commons. The Ofcom review states that UK citizens should expect to see “more intensive use of future bands set aside for licence-exempt applications and perhaps eventually of existing bands, resulting in more exempt devices, higher data rates from existing devices, or a combination of both.” The review paper glances over the fact that new technologies are already in development that could see a vastly more efficient use of the airwaves – including ubiquitous broadband and a level of connectivity and speed far beyond current services. For this to eventuate, a significant shift in communications regulation is required. The current Ofcom review may only be proposing a small shift, but it suggests that incremental change is now underway. Australia’s current regime for spectrum management remains locked into a “property” model, which was developed to accommodate what are now considered to be out-of-date, “dumb” or “impolite” receivers such as standard clock radios and television sets. The assumption behind this arrangement is that spectrum is a scarce resource and that untamed signals result in interference. Therefore, each licensee is allocated a specific frequency on which to transmit their signals, with room in between to ensure that their signals don’t overlap. Although digital transmission technology compresses broadcast signals – allowing for more channels – spectrum is still essentially “limited.” Thus, regulation has tended to allocate portions of spectrum to specific services, in the same way that land is divided for occupancy by land-owners and tenants. Spectrum scarcity has been under fire from technical experts for decades. David P. Reed, one of the internet’s original architects, has been arguing that problem lies not in the amount of spectrum available but in the receivers (“There’s no scarcity of spectrum any more than there’s a scarcity of the colour green”, Reed once stated). In other words, the problem lies not with the amount of spectrum, but with unsophisticated technology. An impolite receiver gets confused if there are two signals at or near the same frequency – because it cannot differentiate between them, information appears garbled at the point of reception. New technologies, such as software-defined radios (SDRs), are able to distinguish between signals, and receive (and relay) information across non-adjacent bands. This “polite” technology has been slow to develop as there has been little use for such devices, given the limitations of spectrum allocation. In January 2002, Wired magazine published an article on tech-guru Dewayne Hendricks, a ham radio enthusiast and former Silicon Valley entrepreneur. The “broadband cowboy,” as he was dubbed, has remained at the forefront of open spectrum technologies – designing, testing and implementing the wireless networks of the future. Since the article was published, Hendricks has been demonstrating that ubiquitous, high-speed broadband can be delivered using radio spectrum, releasing broadband from the constraints of cable whilst maintaining the decentralised, self-regulating structure of the internet. In order to achieve this, Hendricks needed to find some UHF spectrum that would not land him with a court order from the FCC. The solution was to work on Native American lands with communities who were prepared to evade FCC laws on the basis of Indigenous sovereignty. As a result, residents of Sandoval County in New Mexico (home to seven Native American Pueblos, three Navajo Chapters and an Apache reservation) will soon have greater bandwidth coming into their homes than people in the cities with a cable connection. Adding a whole new dimension to the phrase “Backing Indigenous Ability,” Hendricks’s smart radio devices can stretch up to 30 miles across the New Mexican terrain with a two-foot dish using UHF spectrum. So far, the FCC has not tried to stop him or the county from using the spectrum. In fact, Hendricks has a seat on the Federal Communications Commission (FCC) Technology Advisory Council. More technologies (and cowboys/girls) are likely to emerge in a spectrum commons. Opening up spectrum for experimentation is the first step. As Lawrence Lessig suggests in The Future of Ideas: The Fate of the Commons in a Connected World (Random House, 2001) innovation is best stimulated via technologies that allow for widespread participation in their own design. Keeping the barriers to creativity low encourages people to design, develop and extend existing technologies. The argument for unlicensed access to UHF spectrum is therefore more than a matter of equity (the classic “digital divide” argument); it is central to the cultivation of new technologies in the post-industrial economy. Groups at the forefront of community media are also considering a licence-free future. Prometheus Radio in the US began as an advocacy and training group for illegal “microradio” stations. In 2000 they succeeded in convincing the FCC and Congress to create a new class of radio licences, Low Power FM (LPFM), reinvigorating America’s community radio landscape along the way. Prometheus, however, have also continued to challenge the property model of spectrum access which has marginalised community-based media over the past century. They hope that LPFM will be replaced (or complemented) by more of a commons-style, open spectrum regime – something closer to the premise and practices of community media: “If it were possible for the public to directly access the airwaves,” they write, “without having to negotiate with an intermediary – the FCC or one of its sanctioned industry kingpins – then perhaps it would be possible to expand vital community media services to all communities. It may even be possible for community-based communications providers, and home-grown communications tools built in-house by organizations who need them, to grow and thrive to spring up and build out on an as-needed basis.” Such a future is still very far off. The biggest obstacle remains the commercial broadcasting industry. As long as over-the-air broadcasting has a viable business model, commercial broadcasters are likely to resist any attempt to liberate the airwaves. The advocacy group Open Spectrum UK, which has the weight of former BT Chief Technologist Peter Cochrane behind it, has been focusing its efforts on liberating spectrum after analogue switch off. Robert Horwitz, of Open Spectrum International, writes that “opening a licensed band to shared use by unlicensed devices is easier than completely clearing a band of licensed users. So if you think of Open Spectrum as something that can be introduced gradually, this is an important option.” In February, the FCC reiterated its preference to open up so-called white spaces in the broadcast band to unlicensed advanced wireless devices. So far, this doesn’t mean much; we are likely to see long-range baby monitors before any radical change in the communications landscape. But baby steps may one day get us there. • |
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