A Wideband Directional Antenna Based on Hybrid Mode Dipole

This communication presents a wideband directional antenna that consists of a hybrid mode dipole, a feed structure, and a reflector. The hybrid mode dipole is evolved from a conventional half-wave dipole resonating at 1.8 GHz. By adding two open-circuit stepped branches to one of the radiating arms of the half-wave dipole and full-wave modes at 2 and 2.15 GHz can be stimulated. The asymmetric structure of the hybrid mode dipole is beneficial to obtain a large input current near the feed point and good input impedance matching when the antenna works in the full-wave mode. The proposed antenna can provide a 24% bandwidth from 1.7 to 2.17 GHz with a compact size of $65\times 12\times31.5$ mm3 ( $0.41\times 0.08\times 0.2\lambda ^{3}$ ). To verify the design, the single antenna, and its $4\times4$ array is fabricated and tested. Results show that the antenna has a good application prospect in communication systems.