In this paper a broadband radio frequency identification (RFID) tag antenna for the ultrahigh-frequency (UHF) band is designed. The proposed antenna consists of a first-order Hilbert fractal structure and a spiral structure. In order to ensure the conjugate matching between the tag antenna and the electronic chip, a T-matching structure is employed. The interaction between two radiating elements makes the proposed antenna a fractional bandwidth of 20% over the frequency range of 820 MHz-1010 MHz and a small size of 0.2092λ0×0.099λ0. Simulated and measured results validate the good performance of the designed tag antenna.
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