A Wideband Folded Dipole RFID Tag with Improved Impedance Matching Technique

This paper comes up with a novel design of compact and broadband folded dipole tag antenna at 2.45GI3z (Microwave RFID). The compactness is carried out by meander-line structure with a size of 0.35 λ
₀
X 0.3, λ
₀
X 0.002 λ
₀
, where λ
₀
is the free-space wavelength corresponding to the resonant frequency. Input impedance of the antenna can easily be matched with complex embedded IC chip at resonant frequency by means of calibrating the meander arm length and adding a small inductive loop inside the structure. The antenna is fed by this inserted loop. This planar antenna attains a wide bandwidth of 10,.2% with a moderate gain of 3.16 dBi over the operating frequency band. Simplicity and compactness with unique complex impedance matching network makes this wideband planar antenna suitable for microwave RFID tag design.