中文摘要：

本文设计了一种基于磁/电介质混合型基体的宽带超材料吸波体,吸波体基本单元由电阻膜、磁/电介质混合型基体以及金属背板组成.采用时域有限差分法对超材料吸波体吸波性能进行了仿真,使用遗传算法优化了反射率小于-10 d B的带宽.仿真结果表明,当超材料吸波体厚度为2.5 mm时,在7.8—18 GHz频率范围内的反射率小于-10 d B,具有厚度薄、宽带、极化不敏感等优点.通过等效电路模型对其工作机理进行了分析与讨论.最后制备样品进行测试,测试结果与仿真结果一致.

英文摘要：

In this paper, a broadband metamaterial absorber is designed based on a hybrid substrate consisting of the dielectric and magnetic materials. The absorber is composed of the resistance film, dielectric layer, magnetic layer, and metal backboard. Numerical simulation of the absorbing properties is performed by means of the finite-difference time-domain method, and the bandwidth of the reflectivity below-10 d B is optimized by the genetic algorithm. Simulated results indicate that a bandwidth of reflectivity below-10 d B can be achieved over the frequency range from 7.8 to 18 GHz when the thickness of the absorber is only 2.5 mm. The proposed metamaterial absorber has many advantages, such as thin thickness, broadband, and polarization insensitivity. The operation mechanism of the absorber has also been analyzed and discussed within the model of equivalent circuit. In the end, an absorber sample is fabricated based on the design. It is found that the experimental result is well consistent with the design requirements.