Tunable Compact UHF RFID Metal Tag Based on CPW Open Stub Feed PIFA Antenna

<table>Theoretical and experimental read ranges for the open stub feed patch antenna (<i>EIRP</i> = 4 W).</table>

International Journal of Antennas and Propagation

Figure 8: Tunable Compact UHF RFID Metal Tag Based on CPW Open Stub Feed PIFA Antenna 