Enabling 6G Performance in the Upper Mid-Band by Transitioning From Massive to Gigantic MIMO

TL;DR

This paper investigates the transition from massive to gigantic MIMO in the upper mid-band for 6G, analyzing antenna requirements, deployment strategies, and challenges to achieve high performance.

Contribution

It introduces a new deployment strategy leveraging near-field effects and discusses practical considerations for implementing gigantic MIMO in 6G.

Findings

Gigantic MIMO can significantly enhance 6G performance in the upper mid-band.

A practical antenna deployment strategy utilizing near-field effects is proposed.

Open challenges in hardware, cost, and algorithms are identified for future research.

Abstract

The initial 6G networks will likely operate in the upper mid-band (7-24 GHz), which has decent propagation conditions but underwhelming new spectrum availability. In this paper, we explore whether we can anyway reach the ambitious 6G performance goals by evolving the multiple-input multiple-output (MIMO) technology from massive in 5G to gigantic in 6G. We describe how many antennas are needed to reach the envisioned 6G peak user rates, how many can realistically be deployed in practical radio equipment, and what the practical spatial degrees-of-freedom might become. We further suggest a new deployment strategy that enables the utilization of radiative near-field effects in these bands for precise beamfocusing, localization, and sensing from a single base station site. Finally, we identify open research and standardization challenges that must be overcome to efficiently use gigantic MIMO dimensions in 6G from hardware, cost, and algorithmic perspectives.