Rate-Splitting for Multigroup Multicast Beamforming in Multicarrier Systems

TL;DR

This paper proposes a rate-splitting beamforming method for multigroup multicast in overloaded multicarrier systems, improving spectrum efficiency and resource flexibility over traditional techniques.

Contribution

It introduces a novel rate-splitting approach for multigroup multicast beamforming that handles interference and power constraints more effectively.

Findings

Outperforms classic beamforming in spectrum efficiency

Enables simultaneous delivery of multiple messages

Offers greater flexibility in resource allocation

Abstract

In this paper, we consider multigroup multicast transmissions with different types of service messages in an overloaded multicarrier system, where the number of transmitter antennas is insufficient to mitigate all inter-group interference. We show that employing a rate-splitting based multiuser beamforming approach enables a simultaneous delivery of the multiple service messages over the same time-frequency resources in a non-orthogonal fashion. Such an approach, taking into account transmission power constraints which are inevitable in practice, outperforms classic beamforming methods as well as current standardized multicast technologies, in terms of both spectrum efficiency and the flexibility of radio resource allocation.