Reconfigurable intelligent surfaces (RISs), as a promising technology for 6 G
communications, have received considerable attention. Herein, we investigate the downlink …

Recently, reconfigurable intelligent surfaces (RISs) have emerged as a potential technique
for future 6G communications. Considering the practical hardware constraints of RISs, eg …

Hybrid beamforming (HBF) design is a crucial stage in millimeter wave (mmWave) multi-user
multi-input multi-output (MU-MIMO) systems. However, conventional HBF methods are still …

Owing to the unique advantages of low cost and controllability, reconfigurable intelligent
surface (RIS) is a promising candidate to address the blockage issue in millimeter wave …

In reconfigurable intelligent surface (RIS)-assisted wireless communication systems,
channel estimation is of paramount importance to unleash the full advantage of the high …

Reconfigurable intelligent surfaces (RISs) have been proposed as a key enabler to improve
the coverage of the signals and mitigate the frequent blockages in millimeter wave …

To alleviate the high cost of hardware in mm-wave systems, hybrid analog/digital precoding
is typically employed. In the conventional two-stage feedback scheme, the analog …

The focus of this paper is on multi-user multi-input multi-output transmissions for millimeter-
wave systems with a hybrid precoding architecture at the base station. To enable multiuser …

We introduce a novel deep reinforcement learning (DRL) approach to jointly optimize
transmit beamforming and reconfigurable intelligent surface (RIS) phase shifts in a multiuser …

The tradeoff between narrow beams and low training overhead is deemed to a bottleneck for
millimeter-wave (mmWave) systems. Particularly, in multi-user (MU) scenarios, the training …