基于共形超表面的波束聚焦研究

Study of Beam Focusing based on Conformal Metasurface

设计仿真了一款由圆环相切构成的反射型超表面单元,通过改变单元尺寸,10 GHz时其反射系数相位变化可达430°,反射系数幅值大于0.9。基于广义斯涅耳定律和相位梯度原理,将45×45个单元组成超表面阵列,共形于圆心角为90°的部分柱体,可使喇叭天线垂直入射的电磁波实现反射波束在柱面法线方向上的汇聚。仿真结果表明,10 GHz时,共形超表面与金属共形目标体相比,其反射波束的增益提高10 dB以上。通过对共形超表面的研究,可将传统的超表面的应用从平面延伸到曲面上,拓展超表面的实际应用场景。

In this paper,a reflective metasurface unit composed of circles tangent is designed and simulated.By changing the size of the metasurface unit,the phase change of the reflection coefficient can reach 430°,and the amplitude of the reflection coefficient is greater than 0.9 at 10 GHz.Based on the generalized Snell’s law and the principle of phase gradient,the metasurface array consisting of 45×45 elements is conformal to a part of the cylinder with a central angle of 90°.The electromagnetic waves incident vertically on the horn antenna can converge the reflected beam in the normal direction of the cylinder.The simulation results show that at 10 GHz,the gain of the reflected beam increases by more than 10 dB with the conformal metasurface.The conformal metasurface proposed indicate that:the traditional metasurface can be extended from plane to curved surface,and the application of metasurface can be expanded.