透镜和天线的组合可实现更高的增益和更窄的波束，在通信、雷达等领域中具有广泛应用。传统的透镜存在体积大、加工制造复杂等问题，而惠更斯超表面是一种新型的电磁材料，具有灵活调控电磁波的特性，可用于设计小型化的透镜，以满足现代通信和雷达等领域中对小型化器件的需求，因此本文主要基于惠更斯超表面的电磁特性及其在超透镜天线方面的应用展开研究。

针对传统贴片天线辐射方向性差、增益低的问题，设计一个单极化超透镜。基于惠更斯原理，提出了一个透射系数高于0.8时实现相位全覆盖的超表面单元，然后按聚焦相位分布排列组合成超透镜。在5.8-6.3 GHz内，超透镜能够将以0-5°方向入射的y极化波在30-55 mm内汇聚。将超透镜与一个贴片天线组合成透镜天线，在距离天线30-55 mm内，超透镜可以将贴片天线辐射的球面波转化为平面波，提高辐射波束的方向性。与贴片天线相比，超透镜天线的增益提高了11 dBi。通过自由空间法对超透镜天线进行了实验测试，测试结果与仿真结果吻合。

针对当前惠更斯超透镜只能实现单一极化波聚焦的问题，设计一个双极化超透镜。基于惠更斯理论提出了一个透射系数高于0.86时实现相位全覆盖的双极化超表面单元，然后按聚焦相位分布排列成超透镜。在18-21 GHz内，超透镜能够将以0-20°方向入射的x极化波和y极化波在30-55 mm处内进行汇聚。将超透镜加载到贴片天线上，超透镜能够将贴片天线辐射的球面波转化为方向性较高的笔形波束，并将贴片天线的增益最大提升14.57 dBi。通过自由空间法对超透镜天线进行了实验测试，测试结果与仿真结果吻合。

实测结果表明，所设计的单极化、双极化超透镜能够较好地改善贴片天线辐射性能和提高天线增益，为超透镜的设计提供一定的理论参考价值。

The combination of lenses and antennas can achieve higher gain and narrower beamwidth, which has wide applications in communication, radar, and other fields. Traditional lenses have problems such as large volume and complex manufacturing, while the Huygens metasurface is a new type of electromagnetic material with the flexible control of electromagnetic waves, which can be used to design miniaturized lenses to meet the demands of miniaturized devices in modern communication and radar fields. Therefore, this paper mainly focuses on the electromagnetic properties of Huygens metasurface and its application in metalens antennas.

To address the issues of poor radiation directionality and low gain of traditional patch antennas, a single-polarization metalens is designed. Based on the Huygens principle, a metasurface unit is proposed that achieves phase coverage with a transmittance coefficient greater than 0.8, and is arranged in a focusing phase distribution to form a metalens. At 5.8-6.3 GHz, the metalens can converge y-polarized waves incident in the 0-5° direction within 30-55 mm. When combined with a patch antenna, the metalens can convert the spherical wave radiated by the patch antenna into a planar wave within 30-55 mm from the antenna and improve the directionality of the radiation beam. Compared with the patch antenna, the gain of the metalens antenna is increased by 11 dBi. The metalens antenna is experimentally tested using free space methods, and the results match the simulated results.

To address the problem that the current Huygens' metalenses can only focus on single-polarization waves, a dual-polarization Huygens' metalens is designed. Based on the Huygens' principle, a dual-polarized metasurface unit that achieves full phase coverage at transmission coefficients higher than 0.86 is proposed, and then arranged into a metalens according to the focusing phase distribution. At 18-21 GHz, the metalens can converge x-polarized and y-polarized waves incident in 0-20° direction within 30-55 mm from the antenna. When loaded onto a patch antenna, the metalens can convert the spherical wave radiated by the patch antenna into a pencil-shaped beam with high directionality, and increase the gain of the patch antenna by a maximum of 14.57 dBi. The experimental test of the metalens antenna is carried out by the free-space method, and the test results are consistent with the simulated results.

The experimental results show that the designed single-polarization and dual-polarization metalenses can effectively improve the radiation performance of patch antennas and increase antenna gain, providing certain theoretical reference value for the design of metalenses.

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