Linearly Polarized and Dual-Polarized Magneto-Electric Dipole Antennas With Reconfigurable Beamwidth in the H-plane

Linearly polarized and dual-polarized magneto-electric (ME) dipole antennas with a dynamic beamwidth control in the H-plane are presented. The design methodology uses tunable parasitic dipoles placed on the sides of a driven ME dipole along its H-plane. Each parasitic dipole is loaded with a varactor diode to change the strength of the mutual coupling; therefore, the overall radiation pattern produced by the driven ME dipole and the two parasitic dipoles can be tuned. Two fully functional prototypes with more than 10% impedance bandwidths are developed and tested, demonstrating the H-plane beamwidth with a continuously tuning range from 80° to 160° for the linearly polarized antenna and from 72° to 133° for either polarization mode of the dual-polarized antenna. The radiation efficiencies are better than 80% in all states of operation for both antennas.