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Now, there are many, many frequencies that qualify as "unlicensed," but only a handful get used in our phones, routers, and walkie talkies. Frequencies that weren't so high that they sacrificed broadcast penetration (through walls, for example), but weren't so low that they required foot-long antennae. All these gadgets needed frequencies that didn't require licenses, but which were nestled between the ones that did. Our phones were one the cusp of losing their cords, and in the near future, broadband internet connections would come into existence and become magically wireless. The current ISM standards were established in 1985, and just in time. The ISM is, in effect, a ghetto for unlicensed wireless transmission, recommended first by a quiet little agency in a Swiss office of the UN, called the ITU, then formalized, modified and codified for practical use by the governments of the world, including, of course, our own FCC.

If routers and cordless phones and whatever else are relegated to a small band 2.4 GHz, then their radio waves won't interfere with, say, cellphones operating at 1.9 GHz, or AM radio, which broadcasts between 535 kHz and 1.7 MHz. You don't need a license to operate on them." That's Ira Kelpz, Deputy Chief, Office of Engineering and Technology at the Federal Communications Commission, explaining precisely why these ISM bands are attractive to gadget makers: They're free to use. "A lot of the unlicensed stuff - for example, Wi-Fi - is on the 2.4-GHz or the 900-Mhz frequencies, the ISM bands. A band of frequencies clustered around 2.4 GHz has been designated, along with a handful of others, as the Industrial, Scientific, and Medical radio bands.

It seems, well, regulated.Ī glance at FCC regulations confirms any suspicions. The question, then, is why so many of your gadgets operate at 2.4 GHz, instead of the ~2,399,999,999 whole number frequencies below it, or any number above it.