Human-body effects on the design of card-type UHF RFID tag antennas

This paper presents design considerations of a UHF-band card-type tag placed on the packet near the chest of a human body for our University-campus applications. Using FEKO simulation tool, we designed four kinds of highly platform-tolerant tag antennas and evaluated the influences of a simple human model on the power transmission coefficient, radiation pattern, and realized gain. Also, the input impedances of the tag antennas are measured by a test fixture and a two-port network analyzer to verify the simulation results and confirm the availability of the simulation tool. Finally, a better tag antenna is chosen a candidate for student-card RFID applications.