Dualband Wearable UHF RFID Antenna

Based on a system study of the ability to use a commercial RFID system operating in 869 MHz band for the identification of moving sportsmen [1], TAG antennas has been recognized as one of the most sensitive component that affect the proper function of the whole system, especially in case when TAG antenna has to operate in the close vicinity of human body. Single and dual-band weareable patch antenna to cover European (869.5 - 869.7 MHz) and US (902- 930 MHz) RFID bands that are not affected by the presence of human body has been designed, manufactured and measured. The specifics of the design are complex conjugate input impedance to the impedance of the chip used, application of technique to extent the operating band, using of the foam dielectric and conductive cloth. The properties of developed TAG antennas has been compared with meander dipole and patch test antennas in free space as well as in the close vicinity to the human phantom.