Non-Orthogonal Multiple Access and Network Slicing: Scalable Coexistence of eMBB and URLLC

TL;DR

This paper explores how Non-Orthogonal Multiple Access (NOMA) combined with network slicing can enhance the coexistence of eMBB and URLLC services in 5G, ensuring reliability and scalability in dense, latency-sensitive scenarios.

Contribution

It introduces a NOMA-based approach for uplink resource sharing in network slices, improving connectivity and reliability for URLLC in industrial IoT scenarios.

Findings

NOMA enables simultaneous transmission of multiple URLLC users with guaranteed reliability.

Overlapping transmissions with NOMA maintain service quality for both eMBB and URLLC.

The approach improves the number of URLLC users supported in 5G networks.

Abstract

The 5G systems will feature three generic services: enhanced Mobile BroadBand (eMBB), massive Machine-Type Communications (mMTC) and Ultra-Reliable and Low-Latency Communications (URLLC). The diverse requirements of these services in terms of data-rates, number of connected devices, latency and reliability can lead to a sub-optimal use of the 5G network, thus network slicing is proposed as a solution that creates customized slices of the network specifically designed to meet the requirements of each service. Under the network slicing, the radio resources can be shared in orthogonal and non-orthogonal schemes. Motivated by Industrial Internet of Things (IIoT) scenarios where a large number of sensors may require connectivity with stringent requirements of latency and reliability, we propose the use of Non-Orthogonal Multiple Access (NOMA) to improve the number of URLLC users that are connected in the uplink to the same base station (BS), for both orthogonal and non-orthogonal network slicing with eMBB users. The multiple URLLC users transmit simultaneously and across multiple frequency channels. We set the reliability requirements for the two services and analyze their pair of sum rates. We show that, even with overlapping transmissions from multiple eMBB and URLLC users, the use of NOMA techniques allows us to guarantee the reliability requirements for both services.