Optical transparent metasurface lenses and their wireless communication efficiency enhancement
Authors: Li Hao , Pang Yong-Qiang , Qu Bing-Yue , Zheng Jiang-Shan , Xu Zhuo ,   Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi’an Jiaotong University, Xi’an 710049, China,   School of Electronic Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China
Published: June 2024

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.