Privacy-Aware Communication for Smartphones Using Vibration

We propose a novel communication method between smart devices using a built-in vibrator and accelerometer. The proposed approach is ideal for low-rate private communication and its communication medium is an object on which smart devices are placed, such as tables and desks. When more than two smart devices are placed on an object and one device wants to transmit a message to the other devices, the transmitting device generates a sequence of vibrations. The vibrations are propagated through the object on which devices are placed. The receiving devices analyze their accelerometer readings to decode incoming messages. Unlike radio-based wireless communication where eavesdropping of private communication is possible without the knowledge of the user, the proposed method can guarantee privacy as long as the object used for communication is secured. The proposed method is implemented on Android smart phones and comprehensive experiments are conducted to show its feasibility.