Active Filter and RFID Based Identifier for Heartbeat Monitoring

In this work, we present an autonomous system for monitoring the heart rate that has been conceived by using a piezoelectric sensor, an active bandpass filter (ABF) and a Radio Frequency Identifier (RFID) tag combined with an external tag reader. The system can be implemented in a single chip for wearable and portable applications. A sensitive piezoelectric sensor generates a voltage signal from the heartbeat and this signal acts as a control voltage for the ABF and RFID accordingly to the heart rate detection. The piezoelectric sensor and the RFID system that have been considered now are commercial components, while the ABF is the core of the proposed system since it has been designed in such a way that it changes its transfer function allowing the RFID matching, and so the transmission, when a heartbeat occurs.