Don't freak out or anything, but those wireless signals you bask in everyday could be watching you. Or at least they might, someday, if the work from a group of researchers at the University of Utah makes it beyond the lab. As Technology Review's Physics arXiv blog reports, they've devised a means to modify a standard 802.15.4 wireless network (commonly used by home automation services like ZigBee
) to actually "see" movement through walls, and with some degree of accuracy, no less. As you might expect, however, that's not quite as simple as a firmware upgrade, and currently requires a 34-node network to keep watch on a standard living room, which is apparently enough to pin down moving objects within a meter or so. To do that, the system essentially bombards the space with an array of wireless signals and keeps watch on any changes in signal strength, building up a "picture" of the room in the process. No promises on a commercial version just yet, but the researchers see plenty of potential for it, and are even talking about a portable, GPS-equipped version that police or emergency responders could use before entering a dangerous area.