Massive machine-type communications in 5g: physical and MAC-layer solutions

TLDR

Massive machine‑type communications (mMTC) are critical for 5G, requiring scalable, efficient connectivity for billions of short‑packet devices, yet current cellular systems fall short in coverage, cost, and energy efficiency. The study aims to present PHY and MAC layer solutions from the METIS project to overcome mMTC connectivity challenges. The authors develop and describe METIS PHY and MAC layer techniques designed to provide scalable, low‑cost, energy‑efficient connectivity for massive machine‑type traffic.

Abstract

MTC are expected to play an essential role within future 5G systems. In the FP7 project METIS, MTC has been further classified into mMTC and uMTC. While mMTC is about wireless connectivity to tens of billions of machinetype terminals, uMTC is about availability, low latency, and high reliability. The main challenge in mMTC is scalable and efficient connectivity for a massive number of devices sending very short packets, which is not done adequately in cellular systems designed for human-type communications. Furthermore, mMTC solutions need to enable wide area coverage and deep indoor penetration while having low cost and being energy-efficient. In this article, we introduce the PHY and MAC layer solutions developed within METIS to address this challenge.