RAN Slicing Performance Trade-offs: Timing versus Throughput Requirements

TL;DR

This paper analyzes the trade-offs in RAN slicing for 5G uplink scenarios, comparing OMA and NOMA schemes for broadband and intermittent users, highlighting NOMA's advantages in most cases.

Contribution

It provides a comparative analysis of OMA and NOMA for RAN slicing, demonstrating NOMA's superior performance with packet-level coding for diverse service requirements.

Findings

NOMA with packet-level coding achieves near-optimal LR with only 2% throughput loss.

NOMA generally outperforms OMA in balancing throughput and timing constraints.

In extreme cases, OMA can outperform NOMA in throughput at the cost of higher PAoI.

Abstract

The coexistence of diverse services with heterogeneous requirements is a fundamental feature of 5G. This necessitates efficient radio access network (RAN) slicing, defined as sharing of the wireless resources among diverse services while guaranteeing their respective throughput, timing, and/or reliability requirements. In this paper, we investigate RAN slicing for an uplink scenario in the form of multiple access schemes for two user types: (1) broadband users with throughput requirements and (2) intermittently active users with timing requirements, expressed as either latency-reliability (LR) or Peak Age of Information (PAoI). Broadband users transmit data continuously, hence, are allocated non-overlapping parts of the spectrum. We evaluate the trade-offs between the achievable throughput of a broadband user and the timing requirements of an intermittent user under Orthogonal Multiple Access (OMA) and Non-Orthogonal Multiple Access (NOMA), considering capture. Our analysis shows that NOMA, in combination with packet-level coding, is a superior strategy in most cases for both LR and PAoI, achieving a similar LR with only slight 2% decrease in throughput with respect to the upper bound in performance. However, there are extreme cases where OMA achieves a slightly greater throughput than NOMA at the expense of an increased PAoI.