Apple continues work on iDevice security with movement-based theft detection

Filed with the U.S. Patent and Trademark Office, Apple's patent application calls for the use of a portable device's accelerometer, in cooperation with a specialized controller, to detect whether a "theft condition is present" and sound an alarm. The system is slightly less involved than the security invention Apple filed for in mid-October, however the new patent application's reliance on an accelerometer to detect theft is a novel idea.

Integral to the invention's operation is the controller's analysis of signals generated by the movement of a device, which can determine whether the motion matches a set of parameters in which a theft scenario is likely. Just as important is the rejection of signal data for innocuous events.

According to the application, theft conditions are likely to involve large-scale movements, like carrying the device in one's hand, which generate low frequency acceleration signals. Thus, by instituting a low pass filter that allows only those frequencies associated with probable theft scenarios, the risk of a false alarm is significantly reduced.