Flexible and cost effective reconfigurable UHF RFID antenna system

In this paper a reconfigurable matching network for achieving frequency agility of an electrically small UHF RFID patch antenna is proposed. In order to allow switching under high power transmission a state-of-the-art SP3T CMOS switch is employed for selecting specific components and thus achieving a proper matching in the EU and US frequency bands. Moreover, in the proposed design, only one switch is used instead of four needed in standard aperture tuning approaches. An optimized design of a RFID microstrip antenna has been simulated, showing good performance and high degree of flexibility of this technique, which for its low cost and high integration rate, can become an alternative to aperture tuning for frequency agility purposes.