Wideband Printed Half Bow-Tie Antenna Array Based on a Quad-Mode Reconfigurable Feeding Network for UAV Communications

In this article, a wideband printed half bow-tie antenna array based on a quad-mode reconfigurable feeding network for unmanned aerial vehicle (UAV) communications is presented. The proposed array consists of four printed half bow-tie antennas in the top substrate, two supports with a tapered balun, and a reflector with the reconfigurable feeding network in the bottom substrate. For UAV communications caused by wide beam coverage, the proposed reconfigurable feeding network using one single-pole-fourthrow (SP4T) and two single-pole-three-throw (SP3T) switches can adjust the phase and amplitude to the antenna element. By controlling the switches, the proposed array can be operated on four linear polarization modes. The simulated and measured results prove the proposed array reconfigurability of the main beam in four directions with 45° steps in the azimuth plane. In addition, the proposed array achieves the wide 10-dB impedance bandwidth of approximately 29.6% (1507 MHz) from 4.1 to 5.6 GHz. The peak gain and half-power beamwidths (HPBWs) on azimuth and elevation planes of the proposed array are approximately 5.9 dBi, 240°, and 99°, respectively. The overall volume size of the proposed array is 60 × 60 × 18.3 mm3 (~λ0 × λ0 × 0.3λ0 at 5.1 GHz).