A novel triple band antenna for RFID handheld reader

This article presents a novel simple and compact triple band RFID reader antenna for handheld applications. The antenna is a microstrip antenna and fed by a feeding strip. By cutting a rectangular slot on the radiation patch to change the surface currents distribution, and then adjusting the dimensions and position of the rectangular slot to achieve a tri-band antenna. Radiation patch and the ground plane are printed on the opposite side of the substrate, which might be common for multi-layer reader circuitry. The antenna shows broad impedance bandwidths (VSWR <; 2) of 27.9, 15.5 and 14.6% accordingly in UHF (840-960MHz), 2.45 GHz and 5.8 GHz RFID bands and high return loss of 19.04 dB, 20.2 dB and 26.73 dB in the centre frequencies of 0.93, 2.34 and 5.94 GHz respectively. It is worth mentioning that the UHF band of the proposed antenna is universal for UHF RFID applications worldwide.