Analysis on the platform-tolerant radio-frequency identification tag antenna

A new passive radio-frequency identification (RFID) tag antenna for the ultrahigh frequency band is proposed. It consists of a modified inductive feed and a radiating slotted copper trace (SCT). A ground plane is used in the design to make the tag antenna platform-tolerant. The radiating SCT is investigated first, and its return loss, antenna efficiency and radiation pattern characteristics are studied. The read range, differential radar cross section, input impedance and current distribution of the RFID tag that employs the SCT antenna are simulated, and reasonably a good agreement between the simulated and measured results is obtained.