Dual Gradient Descent EMF-Aware MU-MIMO Beamforming in RIS-Aided 6G Networks

TL;DR

This paper introduces a Dual Gradient Descent EMF-aware beamforming scheme for RIS-aided 6G MU-MIMO networks, optimizing capacity while respecting electromagnetic field exposure limits.

Contribution

It proposes a novel Dual Gradient Descent-based beamforming method that accounts for EMF constraints in RIS-assisted 6G MU-MIMO systems, enhancing network capacity.

Findings

Improved network capacity under EMFE constraints.

Effective beamforming design for RIS-aided 6G systems.

Compliance with electromagnetic exposure regulations.

Abstract

Reconfigurable Intelligent Surface (RIS) is one of the key technologies for the upcoming 6th Generation (6G) communications, which can improve the signal strength at the receivers by adding artificial propagation paths. In the context of Downlink (DL) Multi-User Multiple-Input Multiple-Output (MU-MIMO) communications, designing an appropriate Beamforming (BF) scheme to take full advantage of this reconfigured propagation environment and improve the network capacity is a major challenge. Due to the spatial dimension provided by MIMO systems, independent data streams can be transmitted to multiple users simultaneously on the same radio resources. It is important to note that serving the same subset of users over a period of time may lead to undesired areas where the average Electromagnetic Field Exposure (EMFE) exceeds regulatory limits. To address this challenge, in this paper, we propose a Dual Gradient Descent (Dual-GD)-based Electromagnetic Field (EMF)-aware MU-MIMO BF scheme that aims to optimize the overall capacity under EMFE constraints in RIS-aided 6G cellular networks.