A 3GPP Perspective on Spectrum Sharing for the 5G-to-6G Migration: From DSS to MRSS

TL;DR

This paper reviews spectrum sharing strategies from 4G to 5G and explores how lessons learned inform the design of multi radio access technology spectrum sharing (MRSS) for 6G coexistence.

Contribution

It analyzes LTE-NR DSS experiences and discusses how these lessons influence the development of efficient MRSS solutions for 6G.

Findings

Lessons from LTE-NR DSS highlight coexistence challenges.

Efficiency is now the key factor for MRSS success.

MRSS is a promising tool for 5G-6G spectrum migration.

Abstract

Dynamic spectrum sharing (DSS) played an important role in the 4G-to-5G transition by allowing 5G new radio (NR) to enter valuable legacy spectrum without immediate static refarming. Yet practical deployments also exposed the cost of coexistence of NR with long-term evolution (LTE), including overheads, control-channel bottlenecks, neighbor-cell interference, etc. As 6G begins to take shape, spectrum scarcity below 7 GHz is again making 5G-6G spectrum sharing a migration tool of interest. Multi radio access technology spectrum sharing (MRSS) is being considered by the 3rd generation partnership project (3GPP) as a key mechanism for 5G-6G coexistence. This article reviews the lessons learned from LTE-NR DSS and examines how those lessons should shape MRSS design. The main challenge is no longer basic coexistence feasibility, but coexistence efficiency which determines whether MRSS will become a broadly usable framework for 5G-to-6G spectrum migration.