A Contact-Based Data Communication Technique Using Capacitive Touch Screen Panel and Support Vector Machine Classifier

This paper demonstrates a data communication technology based on the capacitive touch screen scheme that can discriminate stylus and finger using a support vector machine (SVM) classifier. The transmitter in a stylus sends the binary data with no-touch and stylus-touch and the receiver in a touch screen panel (TSP) recovers the received data contents. In addition, the proposed transmission protocol implements an artificial finger-touch on the stylus side for initial and terminal codes. Furthermore, to compensate for common-mode drifts caused by HUM noises, upward and downward drift compensation circuits are proposed for the Tx pulse sensing circuit of the transmitter. The proposed method is evaluated by means of 8-inch capacitive TSP, programmable system-on-chip board, and host processor board. It is verified that the proposed method can support the high data rate of 100 bit per second (bps) or more with less bit error rate than 10
^-7
, compared to several bps of previous touch-based communication techniques.