A novel hybrid reflection method is proposed to realize wideband gain enhancement and radar cross section (RCS) reduction properties for Fabry–Perot (FP) antennas. This method adopts two kinds of frequency-selective surface (FSS) units, which are etched on both sides of a single-layer substrate with chessboard arrangement to operate separately as a hybrid surface (HS) and a reflective surface (RS), to form a hybrid partially reflecting surface (HPRS). The two FSSs with different positive reflection phase gradient bands and reflection amplitudes collaborate to expand the 3 dB gain bandwidth and improve the gain enhancement on the RS. Meanwhile, the different compensation phases of the two FSSs can redirect reflected waves to reduce the RCS on the HS, and phase cancellation is applied between the retransmitted waves and reflected waves to further reduce the RCS. The simulated and measured results verify the correctness of the proposed method. The prototyped FP antenna has a measured 10 dB impedance bandwidth of 8.64–12.07 GHz (33.1%), a 3 dB gain bandwidth of 8.6–11.1 GHz (25.4%) with a peak gain of 17.08 dBi at 9.5 GHz, and an RCS reduction bandwidth of 8.6–14 GHz with a peak RCS reduction of 19.5 dB.

中文翻译：

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使用混合反射方法的法布里-珀罗天线的宽带增益增强和 RCS 降低

提出了一种新颖的混合反射方法，以实现法布里-珀罗 (FP) 天线的宽带增益增强和雷达截面 (RCS) 减小特性。该方法采用两种选频表面（FSS）单元，蚀刻在棋盘式排列的单层基板的两侧，分别作为混合表面（HS）和反射表面（RS）工作，形成混合部分反射面 (HPRS)。具有不同正反射相位梯度带和反射幅度的两个FSS协同扩展3 dB增益带宽并改善RS上的增益增强。同时，两个FSS的不同补偿相位可以重定向反射波以减少HS上的RCS，并且在重传波和反射波之间应用相位抵消以进一步降低RCS。仿真和实测结果验证了所提方法的正确性。原型 FP 天线的测得 10 dB 阻抗带宽为 8.64–12.07 GHz (33.1%)，3 dB 增益带宽为 8.6–11.1 GHz (25.4%)，9.5 GHz 时的峰值增益为 17.08 dBi，RCS 降低8.6–14 GHz 带宽，峰值 RCS 降低 19.5 dB。