That is the funny part, and it would work. If you wore conductive clothing you could create a faraday cage around yourself thus preventing RF energy from crossing that boundary.
On a related note, discussing this offline with some friends they pointed out that the pCell system is getting feedback from the phone about its signal strength, and your body wouldn't be giving that feedback, so you would have to have something tied into the pCell on your person (or not move). Your phone could work for that. The question then is how far away from the phone can the energy be localized while the feedback from the phone would still be accurate enough. That I don't know.
Yea that's one thing I'm not sure about is how easily one could create it without that feedback. I'm sure it'd be possible but certainly more difficult.
On a related note, discussing this offline with some friends they pointed out that the pCell system is getting feedback from the phone about its signal strength, and your body wouldn't be giving that feedback, so you would have to have something tied into the pCell on your person (or not move). Your phone could work for that. The question then is how far away from the phone can the energy be localized while the feedback from the phone would still be accurate enough. That I don't know.