Okay I'm as concerned about privasy as everybody else is here but i also gotta admire that its pretty neat they can actually do that. Are they measuring the signal echo like what radar does? If they controlled both the receiver and transmitter i wouldn't be as surprised to find out they can tell when something crosses between them and form a 2-dimensional mesh (like that episode of Star Trek TNG where geordie detects cloaked romulan ships by having starfleet deploy a fleet of ships that send signals back and forth and look for timing variances) but if I'm understanding correctly this is different because they only control a single point in the network?

I wonder if they have enough information to make out shapes or if it's just a simple rangefinder?