Design criteria for full passive long range UHF RFID sensor for human body temperature monitoring

Abstract

Although the insertion of a sensor in a full passive UHF RFID tag for long range is a challenge itself, the main goals of this paper are discussing the real constraints of RFID tags and providing the design criteria to optimize the different blocks in order to achieve long distances. The design has been focused on the matching network, the voltage multiplier, the ASK demodulator, the load modulator and the temperature sensor. The numerical results have been obtained using 0.35 mu m technology from XFAB (XL035) and operating at the 868MHz ISM Europe band.