5G NR-LTE Coexistence: Opportunities, Challenges, and Solutions

TL;DR

This paper reviews the coexistence of 5G NR and LTE, discusses 3GPP solutions, and proposes a new spectrum sharing scheme to enable efficient coexistence and migration.

Contribution

It provides a comprehensive review of LTE-NR coexistence challenges and introduces a novel spectrum sharing scheme for improved coexistence management.

Findings

Catalogs major LTE-NR coexistence scenarios

Summarizes 3GPP contributions to coexistence solutions

Proposes a new spectrum sharing scheme

Abstract

5G New Radio (NR) promises to support diverse services such as enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC). This requires spectrum, most of which is occupied by 4G Long Term Evolution (LTE). Hence, network operators are expected to deploy 5G using the existing LTE infrastructure while migrating to NR. In addition, operators must support legacy LTE devices during the migration, so LTE and NR systems will coexist for the foreseeable future. In this article, we address LTE-NR coexistence starting with a review of both radio access technologies. We then describe the contributions by the 3rd Generation Partnership Project (3GPP) to solving the coexistence issue and catalog the major coexistence scenarios. Lastly, we introduce a novel spectrum sharing scheme that can be applied to the coexistence scenarios under study.