2026-08-12
Reconfigurable Intelligent Surfaces Toward 6G: Technologies, Applications, and Open Challenges
By
Progress In Electromagnetics Research M, Vol. 139, 44-68, 2026
Abstract
Reconfigurable Intelligent Surfaces (RISs) have emerged as a disruptive technology with the potential to fundamentally transform 5G and future 6G wireless communication systems. By intelligently controlling electromagnetic (EM) wave propagation through large arrays of reconfigurable meta-atoms, RIS enables dynamic beam shaping, interference mitigation, coverage enhancement, and energy-efficient communication. This paper presents a comprehensive review of RIS technology, focusing on its fundamental principles, classification, architectural design considerations, and diverse reconfiguration mechanisms. Key aspects, including unit cell structures, material advancements, operating modes, spatial resolution, and control strategies, are examined in detail to provide a holistic understanding of RIS functionality. The review further explores RIS performance modelling, electromagnetic simulation techniques, prototyping methods, and measurement approaches used in evaluating real-world deployments. Emerging application scenarios, including mmWave/THz communications, indoor localization, wireless power transfer, UAV-assisted networks, and smart radio environments, are also highlighted to demonstrate RIS's versatility in next-generation networks. Finally, the paper identifies existing challenges, potential limitations, and future research directions that must be addressed to realize RIS-enabled intelligent wireless ecosystems fully. The insights presented herein aim to guide researchers and industry practitioners in advancing RIS technology as a key enabler for the evolution of future 6G communication systems.
Citation
Nur Hasni Marzuki, Muzammil Jusoh, Thennarasan Sabapathy, Mohamed Nasrun Osman, Muhammad Ramlee Kamarudin, Samir Salem Al-Bawri, and Cihat Seker, "Reconfigurable Intelligent Surfaces Toward 6G: Technologies, Applications, and Open Challenges," Progress In Electromagnetics Research M, Vol. 139, 44-68, 2026.
doi:10.2528/PIERM25122403
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