RFID System for Respiratory Rate Monitoring

Abstract

In this work, an RFID system was developed to monitor the respiratory rate. This monitoring was based on variations in the Received Signal Strength Indicator (RSSI) by the reader due to respiratory movements. In some breath measurement configurations, the maximum read range was greater than 1 m, which is the distance considered in the measurement configurations described in some scientific papers. The RSSI data, obtained by reading the RFID tag, were processed using the Daubechies wavelet of order 3 (db3) and considering three levels of signal decomposition. Less noisy breathing signals were obtained in the measurements with the participant seated and the RFID tag with the polyethylene foam on the abdomen. The respiratory frequencies acquired from the variations of the RSSI parameter were validated by comparison with the results obtained using a vital signals monitor.