A Null-Filled Axisymmetric Secant-Square-Shaped Beam Antenna for Unmanned Aerial Vehicles

In this letter, an antenna with a null-filled axisymmetric secant-square-shaped beam for the unmanned aerial vehicle is proposed. The proposed antenna consists of four monopoles with sequentially rotated feed and a coupling-fed grooved circular patch. The radiation power ratio of the monopoles and the patch is used to shape the axisymmetric beam. The effect of the ground is also investigated to operate positively on beam shaping. A prototype was fabricated to validate the method and the performance of the proposed antenna. The gain curves of the proposed antenna coincide well with the secant-squared (sec(2)) curve from theta = 0 degrees to. = 60 degrees in all azimuthal angles with root mean square error (RMSE) below 1.35 dB in 5.5-5.7 GHz.

Automated summary

In this paper, an antenna design for unmanned aerial vehicles with a null-filled axisymmetric secant-square-shaped beam is proposed. The antenna consists of four monopoles with sequentially rotated feed and a coupling-fed grooved circular patch. The radiation power ratio is utilized for beam shaping, and the ground effect is also examined. A prototype is manufactured to validate the proposed method and antenna performance. The gain curves of the antenna align well with the secant-squared curve in the 0 to 60 degree range, with an RMSE below 1.35 dB at 5.5-5.7 GHz.