This paper presents the design of circularly polarized elliptical patch antenna (EPA) that radiates unidirectional beam. A circularly polarized patch antenna was investigated for the reader of the radio frequency identification (RFID) at ultra high frequency (UHF) band. The center frequency is 923 MHz with the bandwidth from 920 MHz to 925 MHz. The antenna structure is simple because we use the single feed for circular polarization. The prototype antenna was fabricated to measure the antenna characteristics. The pattern is unidirectional pattern with directivity of 8.93 dBi and axial ratio of 1.88 dB at the center frequency. The obtained bandwidth is 15 MHz.
Published in:
Microwave Conference, 2007. APMC 2007. Asia-Pacific
Date of Conference: 11-14 Dec. 2007