The annular slot antenna consists of a circular slot on a square, metal ground plane that is fed by a microstrip line, designed on the bottom of the Duroid substrate. The mean length of the slot circumference is approximately 3 λs/2 at the frequency of 5.8 GHz. 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. Abstract:This paper reports a planar polarization-reconfigurable antenna with a simple switching topology. A dual-mode substrate integrated waveguide (SIW) cavity is adopted for the element antenna having two input ports.
A polarization reconfigurable slot antenna is proposed in this paper. The antenna consists of a microstrip line-to-slotline transition structure, two radiation slots and a switchable feeding network. The feeding network is a gradually changed ring slot with six switching diodes on it. By controlling the diodes states, the antenna can generate y-direction polarization, z-direction polarization, left-hand circular polarization and right-hand circular polarization. Detailed design considerations of the proposed antenna, simulated and measured results are presented and discussed. Measured results agree well with simulated. The results proved that the antenna can realize polarization reconfiguration effectively at 5 GHz.