利用高阻抗表面缩减天线雷达截面的新方法

Application of the high impedance surface for RCS reduction of the antenna

针对现有雷达截面(RCS)减缩技术会导致天线辐射性能退化,体积、重量和成本增加,减缩性能受安装精度影响而不稳定的缺点,提出了一种缩减天线RCS的新方法.将高阻抗表面(HIS)与天线制作于介质板的同一表面,使HIS的同相反射相位带隙的频率与天线工作频率重合,通过高阻抗表面与天线的散射场的对消来减小天线的雷达散射截面,从而实现对垂直照射的天线工作频带内的同极化威胁雷达波的隐身.实验结果表明:在天线工作频带内,其RCS得到了5.3dB以上的减缩,同时,带外RCS亦得到了有效的抑制,S11的-10dB并未展宽,天线间的互耦得到了有效抑制.

This paper investigates the application of the high impedance surface （HIS） to reduce the radar cross section （RCS） of the antenna. The HIS elements are fabricated on the same surface together with the antenna. Around the operational frequency of the HIS elements, the reflection of the HIS and PEC have the opposite phases, so for any normal incident plane wave the reflections cancel out, thereby reducing the RCS. Thus the HIS can be used to reduce the RCS of the antenna which has a PEC surface radiator. To assess the validity of the proposed method, the HIS is employed to reduce the RCS of two microstrip patch antennas. Simulated and measured results show that the RCS in-band of the two mierostrip patch antennas with HIS is reduced by at least 5.3 dB compared with the common antennas, with the impedance bandwidth （S11 ≤ -10 dB） not changed.