A new way to thwart electronic car thieves
Here’s how a man-in-the-middle attack might work for stealing a car: Your keyless entry fob sits on your kitchen table. Unfortunately, the RF signal it puts out is strong enough to reach the outside of your house. A car thief sits just outside your house with his laptop and picks up the keyless fob signal. His laptop relays the fob signal to his accomplice who stands next to the locked door of your car. Using another laptop, the accomplice regenerates the fob signal. Your car thinks the laptop signal is actually coming from the fob. It obligingly opens the door and lets the thieves drive your car away. The way to defeat this scenario, says NXP, is to employ fobs and receivers that incorporate time-of-flight information. So signals originating from a fob that is more than an arm’s length away from the door are ignored. That was the subject of a demo using a UWB chip called the NCJ29D0. A related chip called the DW1000 can be found in a product called Pixie from decaWave which is used to locate missing keys, remotes, pets, and similar household objects. The DW1000 is a single-chip CMOS device based on the IEEE802.15.4-2011 standard.