Abstract:
High-speed train (HST) communication plays a crucial role in providing reliable data services to passengers inside the trains. However, due to the train’s high mobility, ...Show MoreMetadata
Abstract:
High-speed train (HST) communication plays a crucial role in providing reliable data services to passengers inside the trains. However, due to the train’s high mobility, a fast time-varying channel generally exists between the static BS and high-speed users, resulting in severe communication performance degradation. To address this issue, we propose in this paper an intelligent reflecting surface (IRS)-aided HST relaying system, where an IRS is integrated with the relay to aid the data transmission from the BS to the relay. Specifically, an optimization problem is formulated to maximize the received signal-to-noise ratio (SNR) at the relay by jointly optimizing the active transmit beamforming at the BS, the active receive beamforming at the relay, and the passive reflect beamforming at the IRS. To solve this problem, we first decouple it into two simpler sub-problems by leveraging the low-dimensional channel decomposition of the high-dimensional BS-relay channel matrix, and then solve them in closed-form with low complexity. Additionally, an efficient transmission protocol tailored for HST communication systems is proposed to implement channel estimation and beam tracking with low complexity. Simulation results verify the performance gains of the proposed IRS-aided HST relaying system, compared with the traditional relaying scheme without IRS and other benchmark schemes.
Published in: IEEE Transactions on Wireless Communications ( Volume: 23, Issue: 12, December 2024)