Impact of human presence on the read zones of passive UHF RFID systems

In this paper, we study the impact of human presence on the read zones of passive UHF RFID systems using the finite-element method (FEM) with a full length model of a homogeneous human body, consisting of 8 mm tetrahedrals and a total of 334,733 tetrahedrals. The study presented analyses UHF RFID systems operating in the FCC allowed band of 902 MHz to 928 MHz with a typical 7.4 dB gain RFID reader patch antenna located at 0°, 45° and 90° angles in the front, back, top and side of the human body. This paper presents evidence for the first time that allows a visualisation of the deformation of the RFID reader antenna read zones when in the presence of a human body and derives theory using modelling techniques from experimental as well as simulation results.