A Novel Polarization Reconfigurable Annular Ring-Slot Antenna

A novel reconfigurable annular ring-slot antenna with switchable polarization is presented. Circular polarization (CP) radiation of the proposed antenna is obtained by introducing protruded slots and strips in the annular ring-slot structure. Two diodes are used to reconfigure the structure of the annular ring-slot. Switching between right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP) is achieved by turning the pindiodes on or off. The proposed antenna has simple structure and can be controlled easily. An antenna prototype is implemented and the measured results are shown.