基于有源超表面天线罩的窄截面方向图可重构天线

针对无人机数据链通信存在抗干扰性能差、防捕获能力弱等问题,提出了一种具有良好气动性能的基于有源超表面天线罩的窄截面方向图可重构天线。该天线由宽带平面印刷全向天线、窄截面有源超表面天线罩以及双频阻抗匹配网络组成。当超表面天线罩上二极管均截止(未加偏置电压)时,天线罩处于全透波状态,天线工作于宽带全向通信模式。当超表面天线罩特定区域二极管导通时,该区域天线罩处于全屏蔽状态,天线工作于双频定向通信模式,此时通过引入双频阻抗匹配网络显著改善天线的阻抗匹配。全向通信模式下,天线相对带宽达到44.6%,全向增益可达1.37 dBi,不圆度小于2.5 dBi;定向模式下,双频天线上下频带分别为1.4 GHz和1.8 GHz,相对带宽分别为9.1%和15.3%,最大定向增益达5.2 dBi。该天线具有窄截面、低成本等优点,能够在宽带全向通信和双频定向通信工作模式之间灵活切换,有望提高无人机抗干扰、防捕获的性能。

A Narrow Cross-Section Pattern Reconfigurable Antenna Based on Active Meta-Surface Radome

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.