Abstract:Aimed at the problems that military unmanned aerial vehicle (UAV) data link communication is poor in anti-interference performance and weak in anti-captured capability, a narrow cross-section patternreconfigurable antenna is proposed based on an active meta-surface radome with excellent aerodynamic performance.The antenna is comprised of a broadband planar omnidirectional antenna, a narrow cross-section active meta-surface radome with excellent aerodynamic performance, and a dual-frequency impedance matching network. When all the diodes on the meta-surface radome are off (without bias voltage applied), the radome is in a fully transparent state, and the antenna operates in a broadband omnidirectional communication mode. However, when specific diodes on the meta-surface radome are turned on, the corresponding area of the radome becomes fully shielded, and the antenna works in a dual-frequency directional communication mode. In this case, the impedance matching of the antenna is improved significantly by introducing a dual-frequency impedance matching network. In the omnidirectional communication mode, the antenna exhibits a relative bandwidth of 44.6%, a maximum gain of 1.37 dBi, and an out-of-roundness of less than 2.5 dBi. In the directional mode, the dual-frequency antenna has upper and lower frequency bands of 1.4 GHz and 1.8 GHz, respectively, with relative bandwidths of 9.1% and 15.3%. The maximum directional gain can reach 5.2 dBi. The proposed antenna offers the advantages of a narrow cross-section and low cost while allowing flexible switching between broadband omnidirectional communication mode and dual-frequency directional communication mode. The proposed antenna is expected to enhance the anti-interference and anti-capture performance of UAVs.