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Recycling the radio waves

Glaskowsky explains why the planned FCC auction of radio spectrum in the 700 MHz band is so important.

Yesterday, the FCC voted to apply new "Open Platform" rules to a chunk of the radio spectrum in the 700 MHz band, which is being vacated by UHF TV stations. CNET published a good summary of the situation here.

The chunk in question is just 22 MHz wide. Although the details of how this spectrum will be used are up to the winner of the eventual FCC auction, here are a couple of points of comparison. (These numbers could be off; I don't have all the technical details of the new band plan, just the summary from the FCC website here.)

A powerful one-way broadcasting system, like that used for HDTV, could send perhaps 100 megabits per second to any number of people in a metropolitan area-- but everyone in the area would get the same bits.

A cellphone system, on the other hand, with the need to distinguish among many users and support smaller antennae, might deliver 30 megabits/s of aggregate bandwidth within a single cell (split half and half between upload and download bandwidth)-- but a metropolitan area could support many cells.

In short, how the system will be used determines how it will be configured.

The essence of the Open Platform plan is that this spectrum will go to licensees who "will be required to provide a platform that is more open to devices and applications. This would allow consumers to use the handset of their choice and download and use the applications of their choice in this spectrum block, subject to certain reasonable network management conditions that allow the licensee to protect the network from harm."

That's a pretty reasonable summary, but I haven't seen the details.

I'd like to see something like a commercial version of the amateur-radio market. I'm a ham myself (73 de KE6SFO), and I like the way that market works. Anyone can make a ham radio, and as long as it meets FCC standards, it's legal to use it on the air. In fact, an amateur radio operator can build a radio from scratch.

A digital radio for this Open Platform spectrum would be a lot more complicated, but well within the capabilities of many small businesses-- not to mention non-commercial organizations. There are already open-source cellphone development efforts, such as OpenMoko and TuxPhone, though the latter project seems to have gone inactive. Because these projects are aimed at cellphone networks that are very tightly controlled by a few big companies, they may never achieve wide use.

But on this new 700 MHz spectrum, such projects could flourish, and that could only be good for everyone.

There will be more valuable spectrum opening up as TV broadcasting settles into the digital age; I hope more of it will be placed under similar Open Platform rules so we can have several different kinds of networks. It could be a great opportunity for innovation.