Design of RFID reader antennas for UHF RFID handheld systems

Two types of compact wideband UHF reader antennas for handheld applications are proposed. To overcome the narrow bandwidth of a compact patch antenna, an aperture-coupled feeding technique and artificial magneto-dielectric structure are utilized. The proposed antennas have compact sizes of 100 mm × 100 mm × 9.6 mm and 100 mm × 100 mm × 3.2 mm, respectively. In spite of small size, proposed antennas yield the wideband impedance and good axial ratio characteristics. Due to the compact size and wide bandwidth, the proposed antennas are suitable candidates for a handheld RFID reader.