Energy-Efficient Port Selection and Beamforming Design for Integrated Data and Energy Transfer Assisted by Fluid Antennas

2025-03-06

AI Summary

This paper addresses the joint optimization of wireless energy transfer (WET) efficiency and wireless data transmission (WDT) performance in fluid antenna-enabled simultaneous wireless information and power transfer (IDET) systems for 6G low-power scenarios. We first model the latency and energy overhead induced by fluid antenna (FA) port switching—a previously unaccounted factor in IDET design. To tackle this, we propose an alternating optimization framework jointly optimizing transmit-port selection and beamforming, and develop a constraint-aware soft actor-critic (C-SAC) algorithm to maximize long-term WET efficiency under hardware-imposed constraints. The proposed method achieves significant improvements in both short-term and long-term WET efficiency while preserving WDT performance—outperforming existing benchmarks. Key contributions include: (i) the first incorporation of FA port-switching overhead into IDET system modeling; (ii) establishment of a novel WET/WDT co-optimization paradigm; and (iii) a hardware-constrained deep reinforcement learning policy tailored for practical FA-based IDET deployment.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Search and Optimization: Sampling/Simulation-based Search
• Multiagent Systems: Agent Communication

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines

Abstract

Integrated data and energy transfer (IDET) is considered as a key enabler of 6G, as it can provide both wireless energy transfer (WET) and wireless data transfer (WDT) services towards low power devices. Thanks to the extra degree of freedom provided by fluid antenna (FA), incorporating FA into IDET systems presents a promising approach to enhance energy efficiency performance. This paper investigates a FA assisted IDET system, where the transmitter is equipped with multiple FAs and transmits wireless signals to the data receiver (DR) and the energy receiver (ER), which are both equipped with a single traditional antenna. The switching delay and energy consumption induced by port selection are taken into account in IDET system for the first time. We aim to obtain the optimal beamforming vector and the port selection strategy at the transmitter, in order to maximize the short-term and long-term WET efficiency, respectively. The instant sub-optimal solution is obtained by alternatively optimizing the beamforming vector and port selection in each transmission frame, while a novel constrained soft actor critic (C-SAC) algorithm is proposed to find the feasible policy of port selection from the long-term perspective. Simulation results demonstrate that our scheme is able to achieve greater gain in terms of both the short-term and long-term WET efficiency compared to other benchmarks, while not degrading WDT performance.

Problem

• Optimize beamforming and port selection for energy efficiency in IDET systems.
• Address switching delay and energy consumption in port selection for IDET.
• Propose a C-SAC algorithm for long-term port selection policy optimization.

Innovation

• Fluid antennas enhance IDET energy efficiency
• C-SAC algorithm optimizes long-term port selection
• Simultaneous WET and WDT without performance loss