Research Article

A New Sensors-Based Covert Channel on Android

Figure 9

Example of the simple process to smooth the accelerometer signal and applying a dynamic threshold to produce a pulse train in which the width of each pulse is the delay of one of two alternate vibration states, on or off. The hidden message is encoded in those delays: the on state represents one or more 1 bit and off state stands for one or more 0 bits.
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