The UHF-RFID antenna is proposed in this paper using the
elliptical patch antenna to radiate the circular polarization. The
antenna structure is simple because it need only single feeder
and it is free from dielectric loss. The parametric study of the
antenna is presented. It is obvious that the antenna radiates
unidirectional beam with the beamwidth in xz- and yz- planes
are 105 and 75 degrees, respectively. The axial ratio is 1.73
dB and the directivity is 8.92 dBic, respectively. From the
results, it can confirm that this antenna can be used as the
reader antenna of the UHF-RFID system