NR-U and Wi-Fi Spectrum Sharing: Design Challenges and Solutions (database)

This work provides an in-depth analysis of the

Listen-Before-Talk (LBT) procedures that cellular technologies

must adhere to for operation in the unlicensed spectrum. In par-

ticular, we provide detailed insights into the 5G New Radio Un-

licensed (NR-U) standalone design according to the latest 3GPP

standard-compliant Type 1 Channel Access Procedure (CAP).

We highlight some of the challenges and propose improved

mechanisms for channel access. We carry out the performance

evaluation study using a full-stack end-to-end network simulator.

We built a realistic 3GPP-compliant coexistence scenario in which

5G NR-U and Wi-Fi networks operate indoors in the unlicensed

sub-7 GHz bands, and the users of both operators run eXtended

Reality applications. Through an extensive evaluation study, we

analyse the interplay between the NR-U numerologies and the

CAPs used in shared channel access and evaluate their common

impact on the end-to-end performance of both technologies

by considering various quality of service metrics. The results

reveal some of the main pitfalls of the standard-compliant LBT

procedure defined by 3GPP in TS 37.213 and demonstrate the

clear advantages of our proposed solutions. Our work provides

valuable insights and solutions and sets the groundwork for

future research by providing a pioneer open-source network

simulation platform to simulate the coexistence scenarios with

NR-U standalone employing standard-compliant Type 1 CAP.