from the patent, the "detection" system is actually separate from the armor itself, and uses a variety of techniques.

Radars regularly detect things that are very "small" in consideration to their coverage area. There's no reason you couldn't have many of them, to. You could also use visual sensors, as a back up.

The actual system could be quite modest in size. A few wires, some attachment pads, and a power pack/control system the size of a cell phone would do it.

There's ways to defeat it, but there's ways to defeat absolutely any defensive system ever devised. I could see definite uses and applicability for this for stuff like (say) the inauguration or public speaking events.

FWIW, they also DO mention using it on soldiers or a group of soldiers, to protect them from sniper fire, most likely in situations where they'd not normally be expecting it (ie, a field hospital or a depot or such).

Google SMS is much better, almost as good as having an active internet connection.