Wireless spectrum explained: What's the deal with all these MHz, anyway?

Billions are spent by carriers to get a piece of wireless spectrum action

The wireless spectrum, and the way it's regulated by the FCC, can be a little confusing to the novice, but gaining a layperson's understanding of the national airwaves isn't graduate-level stuff.

We’re guessing you know the basics of radio communication, so we don’t need to spend much time on the science – the upshot is that the range of frequencies useful to us for radio communication is somewhat limited. Very low frequencies can’t carry as much information as higher ones, and you need a big antenna to capture their outsized waves. Very high frequencies don’t propagate well through the Earth’s atmosphere, giving them limited range.


Given that, the U.S. government regulates radio communication via the Federal Communications Commission, with the aim of minimizing interference between the huge array of different services using the busiest parts of the spectrum. The FCC currently regulates the spectrum between the frequencies of 9KHz and 275GHz.

In particular, the frequencies between 700MHz and about 3GHz are highly sought-after for their utility in providing mobile data and voice services. A handy dashboard, provided by the FCC, offers an overview of that and more besides.

It’s important to note that the government, technically, owns the airwaves – what Verizon, AT&T, Sprint and T-Mobile are all paying billions for is a license – the exclusive right to operate on a given set of frequencies in a given area.

Licenses range in geographic size and spectrum reach. The 2008 auction for the 700MHz block divided the lower 48 states into just six mega-licenses, while other spectrum is sold in more than 700 individual metropolitan statistical areas (MSA). Auction 96, for the licenses to 10MHz worth of spectrum in the 2GHz range, is happening as of this writing, and uses still a third system – “economic areas,” which are larger than MSAs and smaller than full regions – to subdivide the country into 176 pieces.

So yes, it’s complicated – no question – but it isn’t hard to grasp the general principles.

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