A wideband high-efficiency polarization reconfigurable antenna for wireless communication

A single-feed polarization reconfigurable magneto-electric (ME) dipole antenna is presented in this paper. With the manipulation of the diode states, the proposed ME dipole can provide three states of polarization control (one linear polarization and two orthogonal circular polarizations). To improve the effective bandwidth, antenna efficiency and front-to-back ratio, which are critical for wireless communication system, several techniques including a new excitation method, a low-loss reconfigurable perturbation and a box-shaped reflector are developed or selected after careful examining. The antenna is numerically analyzed and then measured. The fabricated prototype features an effective bandwidth of 7.9%, antenna efficiency of 80–90% and back radiation level below −20dB.