Performance of Uplink NOMA with User Mobility Under Short Packet Transmission

TL;DR

This paper analytically evaluates uplink NOMA performance with user mobility in short packet regimes, deriving PER expressions and insights for ultra-reliable low-latency communication systems.

Contribution

It provides closed-form PER formulas considering mobility and channel correlation, and offers practical power allocation strategies for NOMA in short packet scenarios.

Findings

PER expressions under Rayleigh fading and mobility

Optimal power allocation derived from PER formulas

Insights for ultra-reliable low-latency communication

Abstract

The scenario of an uplink two-user non-orthogonal multiple access (NOMA) communication system is analytically studied when it operates in the short packet transmission regime. The considered users support mobility and each is equipped with a single antenna, while they directly communicate with a multi-antenna base station. Power-domain NOMA is adopted for the signal transmission as well as the successive interference cancellation approach is performed at the receiver for decoding. The packet error rate (PER) is obtained in simple closed formulae under independent Rayleigh faded channels and for arbitrary user mobility profiles. The practical time variation and correlation of the channels is also considered. Moreover, useful engineering insights are manifested in short transmission time intervals, which define a suitable setup for the forthcoming ultra-reliable and low latency communication systems. Finally, it turns out that the optimal NOMA power allocation can be computed in a straightforward cost-effective basis, capitalizing on the derived PER expressions.