Is That Cell Phone Tower Watching Me?

An anonymous reader writes "Cell phone networks, FM radio towers and television antennaes could all turn into pieces of cheap and dirty tracking networks that use passive radar, according to this fairly comprehensive article. These new systems are only a couple years away from roll out for uses such as small airport radar coverage but wild possibilities abound including using cell phone networks to track speeders, terrorists or even individuals walking on city streets."

Comments

Passive vs. Active Systems

[billstewart]

The article's pretty good, though the author does spend a couple of paragraphs confusing what you can do with active vs. passive tracking systems.

It's really really hard for a passive system to track a specific car mixed in with a bunch of other cars, especially if you don't have a solid identification of when it enters and leaves the system, or when there are bridges, tunnels, etc. That's a good job for active systems, like GPS-transmitting bugs or simply the regular signals from cell phones. Passive systems are much better at telling you that _some_ airplane just showed up. Passive systems could tell you that the average speed of cars on the freeway is 25 mph, but it's probably easier to dig that kind of information out of a cell-phone system that tracks the motions of cars into and out of cells, or to use a video processor on a camera, or for that matter those old rubber-hose-across-the-road detectors.