Intelligent reflecting surface-assisted 5G high-speed railway station coverage enhancement technology

To facilitate the digital transformation of railways, the 5G for railway (5G-R) system will become the first choice for railways intelligent connections. This paper employs advanced technologies to promote the new generation railway mobile communication, and conducts a research on intelligent reflecting surface (IRS) assisted 5G high-speed railway station coverage enhancement. In this paper, the ray tracing technology is exploited to accurately model the radio propagation characteristics of the high-speed railway station scenario at the 2.1 GHz frequency band. Based on the accurate radio propagation characteristics, the angle relationship among the reflector, transmitter and receiver, the IRS deployment strategies are proposed, and the corresponding IRS beam direction is designed. After obtaining the channel transfer function influenced by IRS, the path loss (PL) model and the shadow fading model are compared in the case of with IRS and without IRS. The outcomes indicate that the IRS deployment delivers a maximum signal gain of 8.1 dB and an average of 4.63 dB to the target area. The PL index reduce from 2.68 to 2.33, and the standard deviation of shadow fading reduce from 9.45 dB to 6.43 dB. Consequently, the deployment of IRS can significantly improve the radio coverage of the outdoor base station, alleviate the impact of the obstruct of the station buildings on the 5G signal transmission. The research can provide theoretical basis and data support for the design and optimization of the 5G-R system in the station scenario.