高Q值超薄完美吸波体设计方法研究

为了增强完美吸波体的吸波性能，提出了一种高Q值超薄完美吸波体的设计方法. 该方法将基片集成波导技术与一般完美吸波体设计方法有机结合，通过合理添加金属过孔实现了高Q值的完美吸波体设计. 利用该方法设计出了厚度0.0065λ、半波功率带宽5.8%的完美吸波体，其吸波率Q值为33.9，比普通完美吸波体吸波率Q值提升了20%以上；其1.5和3 dBsm的雷达散射截面缩减Q值分别提高了54%和67%以上；同时该方法消除了传统设计中的频率偏移问题. 实测与仿真结果表明所设计的吸波体具有高Q值特征，也具有良好的雷达散射截面缩减效果，散射截面缩减最高达14 dBsm. 仿真和实测验证了设计方法的可靠性. 关键词： 基片集成波导技术 频率偏移 吸波率 雷达散射截面

Design of the ultra-thin perfect metamaterial absorber with high Q-factor

A novel method to design an ultra-thin perfect metamaterial absorber (PMA) with high quality factor (Q-factor) at microwave frequencies is proposed to improve the absorption performance. The PMA achieves a high Q-factor by appropriately loading the metal cavity based on the substrate integrated waveguide (SIW) technology and the common PMA. An ultrathin absorber with a thickness of 0.0065λ and a full-width at half-maximum of 5.8% is designed. The Q-factor of absorptivity of the absorber is 33.9, which is enhanced by 20% compared with that of the conventional PMA. Meanwhile its Q-factors for radar cross section (RCS) reductions of 1.5 and 3 dBsm respectively increase 54% and 67% higher than those of the conventional PMA. The measured results show that the proposed SIW-PMA eliminates the frequency drift between the infinite periodic array and the finite periodic array, which occurs in the conventional design process. The simulated and measured results show that the proposed PMA has high Q-factor of absorptivity and excellent effect of RCS reduction. Its RCS reduction can reach a maximum value of 14.1 dBsm at the response frequency.
Keywords： substrate integrated waveguide technology frequency shift absorptivity radar cross section