Rethinking Fronthaul Topologies for Cell-Free 6G Networks

2026-07-07

AI Summary

This work addresses the trade-off between scalability and performance in fronthaul topology design for cell-free 6G networks with densely deployed antennas. The authors propose and evaluate a Clos-based fronthaul architecture tailored for large-scale cell-free MIMO systems. Through network modeling, scalability analysis, and system-level simulations, they compare tree-based and Clos topologies across varying deployment scales. The results demonstrate that while tree topologies are suitable only for small-scale deployments, the proposed Clos topology achieves near-optimal performance alongside strong scalability in large-scale scenarios, effectively overcoming the limitations of existing solutions.

Abstract

Due to significant progress in physical layer (PHY) technologies, future 6G networks are expected to feature much denser antenna deployments. Cell-free MIMO network designs are one of the most promising candidates to enable denser networks. While significant effort has been put into its PHY research, the challenges it brings to networking disciplines remain relatively unexplored. In this work, we propose various fronthaul network designs for cell-free MIMO. Our results show that while tree topologies may suffice for small-scale deployments, they become infeasible as the number of antennas increases. In contrast, with growing network size, the proposed Clos topology performs almost as well as the optimal topology.

Problem

• fronthaul topology
• cell-free MIMO
• 6G networks
• network scalability
• antenna deployment

Innovation

• cell-free MIMO
• fronthaul topology
• Clos network
• 6G networks
• scalable architecture