Rate-Splitting Random Access Mechanism for Massive Machine Type Communications in 5G Cellular Internet-of-Things

TL;DR

This paper introduces a rate-splitting random access mechanism for massive IoT devices in 5G networks, significantly improving access success rates by utilizing rate splitting and RSMA techniques.

Contribution

It proposes a novel RSRA mechanism that enhances RACH performance for large-scale MTC in cellular IoT, addressing inefficiencies of existing methods.

Findings

RSRA significantly increases RACH success rates.

Performance improves with more devices and higher received power differences.

Extensive simulations validate the effectiveness of RSRA.

Abstract

The cellular Internet-of-Things has resulted in the deployment of millions of machine-type communication (MTC) devices. These massive number of devices must communicate with a single gNodeB (gNB) via the random access channel (RACH) mechanism. However, existing RACH mechanisms are inefficient when dealing with such large number of devices. To address this issue, we propose the rate-splitting random access (RSRA) mechanism, which uses rate splitting and decoding in rate-splitting multiple access (RSMA) to improve RACH success rates. The proposed mechanism divides the message into common and private messages and enhances the decoding performance. We demonstrate, using extensive simulations, that the proposed RSRA mechanism significantly improves the success rate of MTC in cellular IoT networks. We also evaluate the performance of the proposed mechanism with increasing number of devices and received power difference.