Wednesday, November 19, 2008

Obama's FCC guy is big on open spectrum

Today I read perhaps the most positive thing about Obama as I've read in a long time: one of the two people heading his "FCC transition team" is a vocal proponent of open spectrum. His name is Kevin Werbach, and he's written the most complete and compelling open spectrum manifesto that I've ever read (despite the fact that it's six years old). He veers off into silly analogies (the highway analogy halfway through irked me a lot) that muddle his point more than anything, so skip those, but other than that, highly recommended. However, it's really, really, really long, so I've just excerpted some of the best parts.

First, a great two-sentence summary of open spectrum:

The assumptions underlying the dominant paradigm for spectrum management no longer hold. Today’s digital technologies are smart enough to distinguish between signals, allowing users to share the airwaves without exclusive licensing.

And here, an explanation of what interference is, and why it's all relative:

“Interference” is thus highly contingent on real-world factors. Again, this shouldn’t be surprising. Put two television sets next to one another, and you may get a sharp picture on one but a fuzzy image on the other. The difference is that one set has a better tuner. Do we register “interference” when it shows up on one set, or both? Should the most poorly designed set define the requirements for everyone else? What if there is no set in the room but a hypothetical set with certain characteristics might experience a degraded picture there? Under current spectrum policy, such hypothetical “interference” prevents frequency sharing.

Whatever rules we set will influence behavior. If “interference” is defined with reference to a dumb receiver, vendors will try to save money and make receivers as dumb as possible. If, on the other hand, manufacturers have no guarantee of spectrum exclusivity, they will have the opposite incentive. They will build devices robust enough to deal with a variety of situations...

...and this is something I had know idea about: the sinking of the Titanic set the precedence for the laws that still regulate our spectrum. Imagine that...the fate of the Titanic had profound consequences for the telecommunications industry for almost a century!

Here he explains that all of the "science" that current spectrum regulation is based on is flat-out wrong, and we don't even know enough today to say how much we can really jam into the thing (though this question is mostly theoretical...the limit is definitely very high):

Nonetheless, the licensed spectrum model has been the dominant paradigm for so long that there is a surprising amount we simply don’t know about how radios work. For example, we don’t know as a theoretical matter what the maximum capacity is of a geographically defined system filled with randomly distributed radios.

We do know that many of our intuitions are wrong. Research has shown that many factors we believe should decrease the capacity of a system—adding more transmitters, creating more alternative paths for signals to travel, or putting receivers in motion, for example—can actually increase capacity. This occurs because the more data a smart receiver has about the surrounding environment, the better it can do in distinguishing the desired signal.

The commercial viability of any system using these techniques will depend on business conditions.

I'll stop there, because there's just so much in it to quote that I don't even know how to excerpt it all. But if there's one tech-related thing you read this year, it should be this. Let's just hope this guy's thoughts are actually borne out during Obama's presidency.

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