# On the Fundamental Limits of Random Non-orthogonal Multiple Access in Cellular Massive IoT

## TL;DR

This paper investigates the fundamental limits of random non-orthogonal multiple access (NOMA) in cellular massive IoT, analyzing throughput and energy efficiency under realistic conditions with random packet arrivals.

## Contribution

It provides a system performance characterization of NOMA in massive IoT, including stability conditions and analysis of throughput and energy efficiency.

## Key findings

- Derived stability conditions for NOMA in IoT systems
- Quantified throughput and energy efficiency limits
- Analyzed impact of random packet arrivals on system performance

## Abstract

Machine-to-machine (M2M) constitutes the communication paradigm at the basis of Internet of Things (IoT) vision. M2M solutions allow billions of multi-role devices to communicate with each other or with the underlying data transport infrastructure without, or with minimal, human intervention. Current solutions for wireless transmissions originally designed for human-based applications thus require a substantial shift to cope with the capacity issues in managing a huge amount of M2M devices. In this paper, we consider the multiple access techniques as promising solutions to support a large number of devices in cellular systems with limited radio resources. We focus on non-orthogonal multiple access (NOMA) where, with the aim to increase the channel efficiency, the devices share the same radio resources for their data transmission. This has been shown to provide optimal throughput from an information theoretic point of view.We consider a realistic system model and characterise the system performance in terms of throughput and energy efficiency in a NOMA scenario with a random packet arrival model, where we also derive the stability condition for the system to guarantee the performance.