Modeling and Performance Analysis for Fluid Antenna System Enabled UAV Near-Field Communications
2026-08-10 • Information Theory
Information Theory
AI summaryⓘ
The authors study a new way to model and use fluid antenna systems (FAS) on drones to improve their wireless communication with ground users. They create a detailed model that considers how the antenna ports change and how signals behave close to the drone, including the drone's movement. To manage the complexity of multiple antenna ports, they design a smart method to group active antenna parts efficiently, improving signal quality while reducing computation. Their work helps understand how different factors affect communication and supports real-time drone communication using FAS.
fluid antenna systemsunmanned aerial vehiclesair-to-ground communicationnear-field channel modelingline-of-sightnon-line-of-sightsubarray partitioningchannel capacityUAV dynamicsantenna port selection
Authors
Hao Jiang, Wangqi Shi, Zhentian Zhang, Xusheng Zhu, Kai-Kit Wong, Hyundung Shin
Abstract
Fluid antenna systems (FASs) offer a promising solution for unmanned aerial vehicle (UAV) air-to-ground (A2G) communications by enabling reconfigurable radiation characteristics. Addressing the limitations of traditional models in capturing the dynamic port configuration of FAS and the near-field nature of UAV communications, this paper proposes a dynamic port-reconfigurable near-field channel model for FAS-assisted UAV-to-mobile user (MU) links. Furthermore, we develop a FAS-adaptive subarray partition scheme utilizing a greedy strategy. By decomposing line-of-sight (LoS) and non-line-of-sight (NLoS) components and integrating UAV motion dynamics with FAS port activation states, the proposed model accurately characterizes the non-uniform spatial distribution of near-field channels. The subarray partition scheme dynamically groups active ports to satisfy near-field conditions while significantly reducing computational complexity, supported by a dynamic update algorithm that efficiently handles subarray adjustments during port switching. To avoid low effective gain and deep-fading ports in dense FAS configurations, a channel gain-based selection strategy is employed to prioritize high-gain ports. We derive and analyze the modeling accuracy and channel capacity, investigating the impact of FAS dimensions, port spacing, active port count, and UAV dynamics on system performance. Finally, the computational complexity of the subarray partition scheme is evaluated, verifying its advantages for real-time applications and providing a theoretical foundation for the design and analysis of FAS in dynamic scenarios.