Movable Antenna Empowered Downlink NOMA Systems: Power Allocation and Antenna Position Optimization

TL;DR

This paper introduces a movable antenna-enabled NOMA system, optimizing power and antenna positions to enhance channel capacity, outperforming traditional methods in sum rate and outage probability.

Contribution

It proposes a joint optimization framework for power allocation and antenna positioning in MA-assisted NOMA systems, a novel approach in this domain.

Findings

MA-assisted NOMA outperforms OMA in sum rate.

MA-assisted NOMA reduces outage probability.

Joint optimization improves channel capacity.

Abstract

This paper investigates a novel communication paradigm employing movable antennas (MAs) within a multiple-input single-output (MISO) non-orthogonal multiple access (NOMA) downlink framework, where users are equipped with MAs. Initially, leveraging the far-field response, we delineate the channel characteristics concerning both the power allocation coefficient and positions of MAs. Subsequently, we endeavor to maximize the channel capacity by jointly optimizing power allocation and antenna positions. To tackle the resultant non-convex problem, we propose an alternating optimization (AO) scheme underpinned by successive convex approximation (SCA) to converge towards a stationary point. Through numerical simulations, our findings substantiate the superiority of the MA-assisted NOMA system over both orthogonal multiple access (OMA) and conventional NOMA configurations in terms of average sum rate and outage probability.