Polarization Reconfigurable Circular Patch Antenna With a C-Shaped

• Published in: IEEE transactions on antennas and propagation Vol. 65; no. 3; pp. 1388 - 1392
• Main Authors: Mak, Ka Ming, Lai, Hau Wah, Luk, Kwai Man, Ho, Kin Lun
• Format: Journal Article
• Language: English
• Published: IEEE 01-03-2017
• Subjects: Bandwidth; Circular polarization (CP); microstrip antenna; patch antenna; Patch antennas; PIN photodiodes; Polarization; polarization diversity; reconfigurable antennas; Slot antennas; Switches
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2016.2640141

Polarization reconfigurable circular patch antenna with a C-shaped slot is proposed in this communication. It is demonstrated that by introducing a reconfigurable C-shaped slot in a circular patch antenna, the polarization of the radiation of the antenna, operating either in a linearly or circularly polarized mode, can be switched effectively. It is switched between vertical and horizontal polarizations for a linearly polarized mode and switched between left hand circularly polarization and right hand circularly polarization for a circularly polarized mode. The polarization reconfigurable characteristic is realized by controlling the states of the two switching diodes mounted over a concentric circular slot incorporated on the patch, so as to vary the orientation of the C-slot. Prototypes of both linear polarization and circular polarization designs were developed and the performances were validated against measurements. Both antennas exhibit over 20% impedance bandwidth (standing wave ratio (SWR) <; 2) and perform broadside radiation over the operating band. The 3-dB axial ratio bandwidth for the circularly polarized case is 4%.