A beamwidth and beam direction reconfigurable antenna based on multi-mode parasitic coupling

Abstract

A beamwidth (BW) and beam direction (BD) reconfigurable antenna based on multi-mode parasitic coupling is proposed. Two pairs of metal strips connected by only two positive-intrinsic-negative diodes are added as parasitic structures over the driven element, a circular microstrip patch, constituting a simple antenna design. By controlling the diode switching state, four pattern reconfigurable modes can be realised. Two beam-pointing deflection modes in the E-plane are realised based on the Yagi–Uda principle. Besides, the BW reconfigurability is achieved due to a joint effect of the Yagi principle and beam-stacking principle. All the reconfigurable modes share a 10% impedance bandwidth from 5.8 to 6.3 GHz. Simulation and measurement results show that the BW can be switched between 67° and 120° in an omni-directional plane, and the BD can be switched between 0° and ±30° in the E-plane.