SignalTrace can link device signals to your car

Your phone may be giving a roadside sensor clues about where you go and which devices regularly travel alongside you. Say you carpool to work with the same person most mornings. Your car passes a license plate reader, which records the plate along with the time and location. Meanwhile, another sensor detects wireless signals coming from devices traveling nearby. Your phone might be there. So could a smartwatch, wireless headphones or electronics built into the car.

After enough trips, software may recognize that some of those signals tend to move together. Now there is a recurring electronic pattern associated with that vehicle. Weeks later, one of those signals appears somewhere else, perhaps near a different vehicle connected to an investigation. Police may not know who owns the device yet. However, its previous connections could give investigators a place to start.

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