Design of a novel UHF RFID reader antenna for near-field applications

A UHF RFID reader antenna for near-field applications is presented in this paper. The design is based on EM coupling between two open-ended microstrip meander lines. The corresponding currents flowing along the two microstrip meander lines are reverse direction with approximately identical amplitudes. The impedance bandwidth of the proposed antenna is 15 MHz, from 914 MHz to 929 MHz. The results show that the antenna has uniform magnetic field with the reading region of 200 mm × 480 mm × 20 mm and uniform linear electric field with the reading region of 420 mm × 420 mm × 300 mm. Due to the unique characteristics of the antenna, it´s suitable for the commercial near-field applications.