光学透明超表面透镜及其无线通信效率增强

Optical transparent metasurface lenses and their wireless communication efficiency enhancement

玻璃作为目前室内常用的建筑材料,无线信号通过玻璃时较大的插损会降低通信效率.本文设计了一种工作在2.4 GHz Wi-Fi频段的光学透明超表面,通过贴到玻璃两侧将无线信号实现区域聚焦以提高通信效率.为了获得满足区域聚焦的相位设计,超表面由耶路撒冷十字形和圆环两种双层结构组成,透明导电薄膜采用导电性好、光学透明度高的铜网.通过在微波暗室中扫描场强空间分布验证超表面的区域聚焦效果,与空白玻璃对比,在设计的整个聚焦区域均实现7.3 dB以上的场增强,与仿真结果较为符合.进一步测试了不同场景下的下载速度和网速稳定性验证透明超表面玻璃增强无线通信效率.结果表明,在实际使用环境中,设计的超表面玻璃较空白玻璃的下载速度可提高10 Mb/s,且下载速度浮动平稳.本文设计的光学透明超表面结构简单,使用便利,同时具备可移动性,可以根据通信增强需要进行随意摆放,为室内通信增强提供了一种可行的技术途径.

This paper presents the design of an optically transparent metasurface tailored for the 2.4 GHz Wi-Fi band.It is optically transparent and attaches to both sides of the glass to improve communication efficiency.The shape of focusing region is a rectangle with an area of 5 cm by 5 cm and a length of 10 cm.The metasurface attaches to both sides of the glass and realizes area focusing.To meet the requirements for area focusing,the metasurface possesses a double-layer structure of a Jerusalem cross and a circle,and the conductive thin film is a conductive and optically transparent copper mesh.The spatial distribution of field strength in a microwave unreflected chamber is scanned to verify the regional focusing effect of the metasurface.Compared with ordinary glass,the metalens achieves field enhancement of more than 7.3 dB in the designed aggregation region,with an average download speed increasing 20.2 Mb/s.Subsequently,the download speed and network speed stability in different scenarios are tested.The standard deviation is used to calculate the dispersion of the download speed.The results demonstrate that in the focusing area,comparing with ordinary glass,the average download speed of the signal across is increased by 13.8 Mb/s in the indoor environment,accompanied by a reduction in the standard deviation by 0.5.In the stairwell,the average download speed of the signal across of the metalens is observed to increase 12.1 Mb/s,accompanied by a reduction in the standard deviation by 1.4.In conclusion,the metasurface lens demonstrates the better ability to significantly reduce the standard deviation of download speed data in both indoor and stairwell test environments than in air and ordinary glass.This results in the effective smoothing out of the speed uctuations and the enhancing of signal transmission stability.Therefore,the ability of metalens to effectively reduce the amplitude of download speed fluctuations in various indoor environmental contexts confirms its key role in adapting to complex environments and improving the wireless communication performance.Moreover,the download speed of signals passing through the metalens is increased by more than 12 Mb/s in both test environmentsthan that of ordinary glass.This effectively improves not only the signal strength but also the communication efficiency.Concurrently,the designed optically transparent metasurface lens is straightforward in structure and user-friendly,and at the same time,it is moveable and can be positioned according to the needs of communication enhancement.The optically transparent metasurface lens scheme proposed in this study provides a potential solution to the high penetration loss problem currently encountered in indoor wireless communication.