Enormous Fluid Antenna Systems (E-FAS): Rethinking the Future of Wireless Communications

Enormous Fluid Antenna Systems (E-FAS): Rethinking the Future of Wireless Communications | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Enormous Fluid Antenna Systems (E-FAS): Rethinking the Future of Wireless Communications Kai Kit Wong, Kin-Fai Tong, Haizhe Liu, Wee Kiat New, Fan Wun, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8002084/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 9 You are reading this latest preprint version Abstract For decades, wireless communication embodied the promise of ubiquitous connectivity---radio waves weaving invisible paths through obstacles to connect distant nodes. However, as next-generation mobile systems increasingly shift toward higher frequency bands to meet escalating data demands, the wireless channel has become more fragile---exhibiting reduced penetration, limited coverage, and heightened sensitivity to environmental conditions. Concurrently, with the majority of mobile services now taking place indoors, it is both timely and imperative to rethink how wireless connectivity is delivered to achieve greater performance and efficiency. In this article, we address this challenge by reviewing a novel concept that reimagines intelligent surfaces---not merely as passive smart reflectors, as in conventional reconfigurable intelligent surfaces (RIS)---but as multifunctional electromagnetic (EM) interfaces capable of both signal routing and emission. This expanded functionality introduces a fundamentally new degree of control over signal propagation. We define the concept of the enormous fluid antenna system (E-FAS), which conceptualizes a distributed ensemble of intelligent surfaces as a single, massive, reconfigurable antenna embedded within the environment itself. E-FAS enables signal propagation to predominantly occur along surfaces, thereby enhancing energy efficiency, reducing interference, and ensuring reliable service delivery. Crucially, it guarantees that users are served with a line-of-sight (LoS) path---either through direct contact with the surface itself or via short-range wireless links radiated from nearby surface elements. We further explore the potential of deploying E-FAS on building exteriors to guide radio waves around structural obstructions, enabling the restoration of LoS connectivity for users located behind buildings. This vision positions E-FAS as a transformative architectural paradigm for future wireless systems. Physical sciences/Engineering Physical sciences/Mathematics and computing Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 14 Dec, 2025 Reviews received at journal 14 Dec, 2025 Reviews received at journal 05 Dec, 2025 Reviewers agreed at journal 16 Nov, 2025 Reviewers agreed at journal 11 Nov, 2025 Reviewers invited by journal 10 Nov, 2025 Editor assigned by journal 10 Nov, 2025 Submission checks completed at journal 10 Nov, 2025 First submitted to journal 31 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8002084","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":545718896,"identity":"3e336079-06dc-46d3-a1ec-1e74f9caa7f5","order_by":0,"name":"Kai Kit 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