Touch Detection System for Mobile Terminals

Knowledge when the terminal is in the hand of the user is important information that can be exploited in mobile applications. We present a touch detection system for mobile terminals based on impedance measurements. Experiments for recognizing touch of various objects are presented. The results show that the system is capable of recognizing if the device is touched with different objects such as bare hands, cotton (used e.g. in pockets of trousers) and leather carrying case.