Wideband and Low-Profile Omnidirectional Circularly Polarized Patch Antenna

• Published in: IEEE transactions on antennas and propagation Vol. 62; no. 8; pp. 4347 - 4351
• Main Authors: Pan, Y. M., Zheng, S. Y., Hu, B. J.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.08.2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna measurements; Antennas; Applied sciences; Bandwidth; Business and industry local networks; Circular polarization; Circularity; Exact sciences and technology; Frequency measurement; Ground plane; Guidelines; Impedance; low-profile antenna; Networks and services in france and abroad; omnidirectional antenna; patch antenna; Patch antennas; Product design; Prototypes; Radiocommunications; Reflection coefficient; Telecommunications; Telecommunications and information theory; Teleprocessing networks. Isdn; Wideband; wideband antenna; Wireless LAN; Prototype; Parametric analysis; Circular polarization; Wireless telecommunication; Non directive antenna; Printed antenna; patch antenna; Broadband antennas; Antenna gain; Impedance matching; Wide band; Simulation; omnidirectional antenna; wideband antenna; Radiation pattern; Axial ratio; low-profile antenna; Reflectance
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2014.2323412

A wideband low-profile omnidirectional circularly polarized (CP) patch antenna is proposed and investigated in this communication. The design utilizes two monopolar modes of a circular patch which connects to a modified ground plane by a set of conductive vias, to achieve wide-band impedance matching. The curved branches introduced at the edge of circular ground plane excite a degenerate mode and create CP fields. To verify the design, a prototype operating at 2.4 GHz-WLAN band has been fabricated and measured. Measured reflection coefficient, axial ratio (AR), radiation pattern, and antenna gain agree well with simulation results. The proposed prototype has a low profile of 0.024 λ0, a 10-dB impedance bandwidth of 19.8% and a 3-dB AR bandwidth of 19.3%. To further characterize the design concept, a parametric study of the proposed antenna is carried out using HFSS, and general design guidelines are provided.