Beamwidth reconfigurable slotted-patch antennas

A design for beamwidth reconfigurable antennas is described. The antenna structure is mainly composed of dual coplanar slotted-patch antennas fed with a power divider, a metallic reflector, and several PIN diodes. By controlling the states of the diodes, the operation of the slotted-patch antennas can be switched between a slot mode and a monopole mode, and the two modes can respectively generate unidirectional radiations with narrow beamwidth and wide beamwidth. Accordingly, A beamwidth reconfigurable prototype is constructed, and the experimental results show that the prototype operating between 2.15 and 2.53 GHz can offer broadside radiations with H-plane half power beamwidths of 130°±10° and 55°±1° besides, for each radiating mode, good impedance matching and low cross polarization are also achieved within the operating bandwidth.