Re: Got to hand it to Microsoft Research
But the whole point of using radio is to make it less easy for the wrong people to capture your information.
Errm, if it's acoustic, then it's not radio. Radio is an electromagnetic emission, acoustics are sound pressure waves. So it's not "software defined radio" as the article describes, it's a software defined modem, but no radio involved.
The idea sounds interesting… 1200 baud AFSK modems abound as mobile apps and elsewhere, there's one called APRSDroid that I use almost daily on my phone (although I have it just report via the Internet, I can plug the headset jack into a radio transceiver and use RF that way). I just hope that on top of the "jamming" they also incorporate some sort of crypto, either public-key variety or maybe use Diffie-Hellman key exchange to derive a shared secret.