A Circular Polarized Metallic Patch Antenna for RFID Reader

A novel single feed circularly polarized metallic patch antenna for RFID reader is proposed. The proposed antenna has a simple structure, it has corner truncated square patch, ground plane and a probe feed. In addition to structure of the proposed antenna is simple and low cost. Experimental results of a constructed prototype with the center operating frequency at 911 MHz showed that the antenna has an impedance bandwidth (2: 1 VSWR) of about 23 MHz, a 3 dB axial ratio of about 9 MHz, and a gain level of about 9 dBi.