A Novel Multi-polarization UHF RFID Reader Antenna for Near-field Applications

A novel multi-polarized UHF RFID reader antenna for near-field applications is presented. Based on capacitive coupling and standing-wave structure, the antenna is designed and fabricated by microstrip lines. By designing the number of units that consists of an antenna, the interrogated area can be adjusted flexibly and easily. In the interrogated area, the antenna can generate uniform and multi-polarization electric field distributions to detect arbitrarily oriented linearly polarized tags in the horizontal plane. The measured results show that the antenna achieves impedance matching from 893 to 935 MHz.