I've been following the discussion of using so called white space as yet another wireless data channel for some time now. And I've been back and forth in my opinion of whether the concept might work and whether deployments should be licensed. There's certainly been a lot of recent activity and several recent articles that you might want to peruse on the subject. For now I'm thinking that the bulk of the white space may have to be licensed to move the technology forward, although I'm not terribly comfortable with some of the consequences of licensing.
If you haven't followed the discussion, white space refers to unused TV channels and also the space called guard or buffer bands between used channels. In any given market, many channels lay unused and the buffer bands add to the potentially available spectrum. White space proponents see that unused spectrum as a resource that should be leveraged and claim no negative impact of doing so. Not everyone agrees. Wireless microphones use the space already although arguably the makers of such products are homesteaders of the spectrum at best.
If you want more detail, Jack Shandle recently wrote an excellent white space article that appeared in EE Times. I also recently clipped a Washington Post article that ran locally in our San Diego Union Tribune. The article portrayed Qualcomm as one of the major proponents of licensing white space " thus the San Diego angle. You can also find a recent story on the topic over at TechInsights' competitor EDN.
I don't think we'll see the white space technology deployed in any form very quickly. Proponents such as Google clearly think that if unlicensed deployment were allowed that there would be a groundswell of products and deployment that many liken to what happened with Wi-Fi. What most people either don't remember or never knew is that companies such as Lucent Technologies (pre Agere) and the old Proxim worked on wireless LAN in the background for a decade before it became a technology hit. Any white space deployments will wait on a lengthy standards battle, and for unlicensed to work, development of new technologies to avoid interference with other wireless schemes. I realize that work is happening in these areas but these things always take far longer that what one might reasonably expect.
I think the technology could probably move forward more quickly with licenses sold to a few broadly-based service providers. Unfortunately that might mean dealing with the same inept carriers we deal with today in the mobile wireless space. But licensed deployment on a regional basis would allow for an authority to approve the channels that a service provider might use in a defined geography. Moreover it would allow the service provider to turn-up transmit power and serve a wider range of subscribers. One of the reasons that the spectrum in question is seen as very valuable is because of range and the ability of the signals to travel through walls.
Still I'm a Wi-Fi fan and have lived the advantages of unlicensed deployment. It would be nice if perhaps there was a way to carve out an unlicensed niche. Unfortunately the white-space frequency map looks different in every city. So I'm not sure how reserving a piece of the spectrum for unlicensed usage might work. Perhaps unused channels could be reserved for licensing while the no-license crowd could get the buffer bands assuming that they can develop non-interfering technology work. But the service providers don't want to invest money and have free competitors in similar spectrum.