Fluid Antenna Multiple Access Assisted Integrated Data and Energy Transfer: Outage and Multiplexing Gain Analysis

TL;DR

This paper investigates a fluid antenna multiple access system integrated with data and energy transfer, deriving outage probabilities and analyzing multiplexing gains to optimize performance trade-offs for low-power wireless devices.

Contribution

It introduces a novel FAMA-assisted IDET system with closed-form outage probability analysis and explores port selection strategies for improved data and energy transfer performance.

Findings

Closed-form outage probabilities for WDT and WET are derived.

Optimal port selection enhances the trade-off between data and energy transfer.

System performance improves with the number of UEs optimized for IDET.

Abstract

Fluid antenna multiple access (FAMA) exploits the spatial opportunities in wireless channels to overcome multiuser interference by position (a.k.a.~port) switching, which can achieve better performance compared to traditional fixed multiple-input multiple-output (MIMO) systems. Additionally, integrated data and energy transfer (IDET) is capable of providing both wireless data transfer (WDT) and wireless energy transfer (WET) services towards low-power devices. In this paper, a FAMA-assisted IDET system is investigated, where a base station (BS) equipped with $N$ fixed antennas provides dedicated IDET services towards $N$ user equipments (UEs). Each UE is equipped with a single fluid antenna, while the power splitting (PS) approach is conceived for coordinating WDT and WET. The outage probabilities of both WDT and WET are derived and approximated into closed-forms, where the fluid antenna (FA) at each UE selects the optimal port to achieve the maximum signal-to-interference-plus-noise ratio (SINR) or the energy harvesting power (EHP). The IDET outage probabilities are defined and subsequently derived and approximated into closed-forms. Further, multiplexing gains of the proposed system are defined and analyzed to evaluate the performace. Numerical results validate the theoretical analysis, while also illustrate that the trade-off is achieved between WDT and WET performance by exploiting different port selection strategies. Furthermore, the number of UEs should be optimized to achieve better IDET performance of the system.