Polarization reconfigurability patch antenna with improved axial ratio bandwidth

In this paper, the patch antenna with polarization reconfigurability feature is proposed. The antenna composed of circular patch on the top substrate embedded with four equal-length slits, and is fed at the diagonal of the structure using the coaxial fed technique. To obtain the reconfigurability feature, four switches (copper strips) are appropriately located at the specific position across the slit. This will change the slot length, and then consequently altered the polarization excited by the antenna. By controlling the state of the switch, the polarization of the proposed antenna is able to be reconfigured between linear polarization, left-hand circular polarization and right-hand polarization. Triple layers of substrate are utilized in the design in order to have the broader axial ratio bandwidth. The simulated results of the proposed antenna are presented and discussed. This antenna is operated and covered the whole wireless local area network (WLAN) frequency band.