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Share that spectrum

"Now that all those greedy broadcasters have had to give up those free channels the government gave them, we can get some real products and services in that space."

I wanted to crawl through the PC monitor as I read the above excerpt from a blog post. The writer was complaining that TV stations had been sucking up all the spectrum for their greedy owners and was only now reluctantly giving it up because of government mandates. The post was probably being written by some goofball who wouldn’t know Hertz from hurts.

Another article I read called for “free spectrum for everyone.” Geez!

The basis for this writer’s perspective is a set of position papers from the New America Foundation. According to the article’s author, “spectrum is abundant if you treat it right.” Want to see how these think tank experts think spectrum should be used? Here’s how this guy explains it.

For example, weather radar and traffic control radar are really only part-time users of spectrum. You see, the radar is really looking at one direction at a time. That means if the transmitted beam width is but a few degrees, say 15 degrees, there’d be 345 degrees of space that “smart radios” could use. While that geographic space would constantly change as the radar turns, a smart radio with “knowledge of the transmitter’s behavior” could share the band with the radar systems.

Now I don’t know about you, but I’m okay with traffic and weather radar systems being given exclusive use of certain spectrum. Keeping planes from bumping into each other and being able to tell people if there’s a tornado bearing down on their house is really important to me. I’d prefer that Marge’s baby monitor and George’s Wi-Fi connection not interfere with those services. But, that’s exactly what these "experts" are claiming should be done.

The key, according to them, is a combination of smart radios and a comprehensive database of local authorized transmitters. Somehow, the individual smart radio is supposed to “tap into a vast database” that will tell it what frequencies to avoid or use based on the radio’s location. Here is one example the article writer promotes. Suppose the Air Force uses a frequency for missile testing, but in only three U.S. locations. "Everyone else could make use of the band thanks to the database.” Uh, don’t ya think we need to be sure the Air Force’s missile isn’t misdirected by some apartment’s Wi-Fi connection that’s been equipped with an illegal power booster?

The New American Foundation’s vice president and director of the Wireless Future Program, Michael Calabrese, claims that a 2004 study showed that the “highest occupancy on the prime beachfront spectrum below 3GHz was just 13 percent in New York City. “The average across locations studied was just 6 percent.”

New America’s staffers are big backers of the FCC’s white space initiative (despite the fact that the smart radios didn’t work), and now that Google’s Eric Schmidt is in charge of Obama’s new think tank, expect real changes in spectrum usage. Combined, these are the kind of people who will be making recommendations on spectrum usage.

Add to this all the reception problems that were revealed when VHF TV stations discovered that their signals didn’t propagate as well as expected, do you really want to share your spectrum based on the performance of some offshore manufactured radio whose company couldn’t care less how well it worked?

I expect this financial (not technical) battle to be controlled by those with political connections to the current administration — not engineers who understand that RF doesn’t respect state boundaries, or always behave as predicted.