WTF??? Your daughter has a 'cell phone problem' and you applaud the school for taking care of YOUR problem?? When did it become the school district's PARENTAL RESPONSIBILITY in the matter?
Take a little responsibility for the actions of your offspring!
AFAIK (yes, I did RTFA), this is tantamount to adding another method of data transmission using more of the envelope. You still have the frequency being used and still have a portion of the carrier plus sideband transmitted, no matter what type or method of transmission is used. This may be used to embed something similar to a sub-carrier, or a unique identifier. More directivity and narrower beamwidth during point-to-point transmissions will do wonders to keep the RF floor down.
If this reduces the waste to a stable (somewhat non-radioactive state) then I'm all for it. But where does the energy come from to convert this? Is this going to require as much energy to render the "sludge" safe enough to dispose of? Or is this another 'Flash in the Pan'? (Sorry, couldn't help myself).