Broadband CPW-Fed Circularly Polarized Square Slot Antenna With Three Inverted-L-Shape Grounded Strips

• Published in: IEEE antennas and wireless propagation letters Vol. 10; pp. 274 - 277
• Main Authors: Felegari, N, Nourinia, J, Ghobadi, C, Pourahmadazar, J
• Format: Journal Article
• Language: English
• Published: New York IEEE 2011; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna measurements; Axial ratio (AR); Bandwidth; broadband; Broadband antennas; Broadband communication; circularly polarized (CP); Slot antennas; square slot antenna
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2011.2135832

A new form CPW-fed broadband circularly polarized square slot antenna (CPSSA) with three inverted-L-shape grounded strips around the corners of the slot is proposed and fabricated. In comparison to the previous CPSSA structures, the axial-ratio (AR) bandwidth of the antenna is increased, which is two times wider than the previous proposed design. By embedding the L-shape strip to the ground plane and using the vertical stub to the feed line, very good axial-ratio bandwidth is obtained. The measured impedance bandwidth and AR of the realized CPSS antenna with optimized parameters is from 2 to 7 GHz (3.5:1, 110%) for VSWR ≤ 2 and 2-5 GHz (2.5:1; 85%) for AR ≤ 3 dB respectively. Throughout this letter, the improvement process of the AR and S 11 properties is completely presented and discussed.