MIMO Evolution toward 6G: End-User-Centric Collaborative MIMO

TL;DR

This paper proposes a collaborative MIMO framework for 6G that groups multiple devices to create a virtual array of antennas, overcoming space limitations on user equipment and enhancing performance.

Contribution

It introduces the UE-CoMIMO framework utilizing device collaboration with relays to improve diversity, rank, and localization in 6G networks, supported by system-level simulations.

Findings

Significant performance gains demonstrated through simulations

Device collaboration enhances diversity and localization

Framework addresses antenna space limitations on user devices

Abstract

In 6G, the trend of transitioning from massive antenna elements to even more massive ones is continued. However, installing additional antennas in the limited space of user equipment (UE) is challenging, resulting in limited capacity scaling gain for end users, despite network side support for increasing numbers of antennas. To address this issue, we propose an end-user-centric collaborative MIMO (UE-CoMIMO) framework that groups several fixed or portable devices to provide a virtual abundance of antennas. This article outlines how advanced L1 relays and conventional relays enable device collaboration to offer diversity, rank, and localization enhancements. We demonstrate through system-level simulations how the UE-CoMIMO approaches lead to significant performance gains. Lastly, we discuss necessary research efforts to make UE-CoMIMO available for 6G and future research directions.