随着Wi-Fi和5G技术的迅速发展，对宽带、高增益、低剖面、小型化等高性能天线的需求日益迫切。超材料及其二维形式的超表面均可任意地调控入射电磁波的幅度、相位和极化等电磁参数，因此，高性能超表面天线的设计具有重要意义和应用价值。

（1）设计了一种加载超表面的WLAN天线。在矩形贴片天线的基础上，通过开槽实现双频WLAN天线，进一步加载对应于工作频段的双负超表面来提高天线的增益并改善其阻抗匹配水平。所设计的超表面天线工作带宽分别为2.27GHz~3.45GHz和5.32GHz~6.26GHz，相对带宽分别为41.2%和16.2%，最大增益为8.6dB，且在2.4GHz和5.8GHz两个频点处的增益较未加载超表面的天线分别提高了10.1dB和5.7dB，与同类天线相比，具有高增益的优势。

（2）设计了两种应用于Sub-6GHz频段的超表面天线。首先，通过在WLAN天线中心嵌入圆环来实现目标频率，并设计渐变式馈电结构来展宽带宽，所设计的天线工作带宽为3.08GHz~5.18GHz，相对带宽为50.8%，最大增益为3.6dB。其次，通过研究超表面对天线性能的影响机理，设计了一种正方形的双负超表面，使天线在4.28GHz~5.14GHz频段内最大增益提高至9.84dB。进一步通过改变该正方形双负超表面结构的排列和布阵方式，得到了一种多频双负超表面，将其加载在天线背板后的0.5mm处，使天线的工作带宽为3.02GHz~6.49GHz，相对带宽为73%，比未加载超表面的天线展宽了22.2%，且最大增益为5.8dB，超表面天线尺寸为70mm*70mm*4.1mm，剖面高度仅为0.04λ（λ为最低工作频率所对应的波长）。以上两种超表面天线与同类天线相比，分别具有高增益和宽带低剖面的优势。

基于超表面的高性能天线，同时具备结构紧凑、宽频带、低剖面、高增益和低成本等多个优点，为室内通信系统及宽带无线通信提供高质量的天线设计方法。

With the rapid development of Wi-Fi and 5G technology, the demand for broadband, high gain, low profile and miniaturization antennas is increasingly urgent. Metamaterials and their two-dimensional metasurface can arbitrarily regulate the amplitude, phase and polarization of the incident electromagnetic wave. Therefore, the design of high-performance antennas assisted by the metasurface has important significance and practical value.

Firstly, A WLAN antenna via loading with a metasurface is designed. On the basis of the rectangular patch antenna, a dual-band WLAN slotting antenna is realized; and a double negative metasurface corresponding to the working frequency band is further loaded to increase the gain of the antenna and improve its impedance matching level. The designed antenna has working bandwidths of 2.27GHz~3.45GHz and 5.32GHz~6.26GHz, the relative bandwidths of 41.2% and 16.2%, maximum gain of 8.6dB, at 2.4GHz and 5.8GHz. Compared with the antenna without loading the metasurface, the gain of the antenna is increased by 10.1dB and 5.7dB, respectively. Compared with similar antennas, it has the advantage of high gain.

Secondly, two metasurface antennas for Sub-6GHz frequency band are designed. The target frequency is achieved by embedding a circular ring in the center of the WLAN antenna, and a gradual feeding structure is designed to broaden the bandwidth. The designed antenna working bandwidth is 3.08GHz~5.18GHz, the relative bandwidth is 50.8%, and the maximum gain is 3.6dB. Secondly, by studying the influence mechanism of the metasurface on the antenna performance, a square double negative metasurface was designed to increase the maximum gain of the antenna to 9.84dB in the 4.28GHz~5.14GHz frequency band. Further by changing the arrangement of the square double negative metasurface structure And the array method, a multi-frequency double-negative metasurface is obtained, which is loaded at 0.5mm behind the antenna backplane, so that the working bandwidth of the antenna is 3.02GHz~6.49GHz , and the relative bandwidths are 73% , which are 22.2% wider than the antenna without a metasurface, and the maximum gain is 5.8dB. The size of the metasurface antenna is 70mm*70mm*4.1mm, and the profile height is only 0.04λ(λof the lowest operating frequency point Wavelength). Compared with similar antennas, the above two metasurface antennas have the advantages of high gain and broadband low profile respectively.

The high-performance antenna assisted by the metasurface has the advantages of compact structure, wide-band, low profile, high gain and low cost. It provides the high-quality antenna design solutions for indoor communication systems and broadband wireless communications.

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