A Review on Intelligent Reflecting Surfaces: Challenges and Opportunities Towards Secured Communications

Abstract

ABSTRACTThis review examines the advanced development and implementation of intelligent reflecting surfaces (IRSs) in smart radio environments (SREs) to enhance secure communications. IRS technology, including intelligent walls and software‐controlled metasurfaces, is designed to manipulate electromagnetic waves, thereby significantly improving wireless communication. The study highlights the importance of dynamic, nearly passive IRS, which combine multiple elements to create surfaces capable of diverse wave manipulations. Cutting‐edge techniques such as nonorthogonal multiple access (NOMA) and machine learning are employed to optimize IRS functions, enhancing secrecy rates and resilience against eavesdropping. Despite their ease of reconfiguration and affordability, IRSs are vulnerable to several security threats, a concern that has not been extensively explored in current research. This review aims to fill this gap by offering a comprehensive analysis of the security challenges associated with IRS‐enabled wireless networks. The effectiveness of IRS is compared to traditional wireless relays, with special attention to the simultaneous transmitting and reflecting intelligent reflecting surface (STAR‐IRS) model that provides 360° coverage. Key findings suggest that IRS can greatly enhance secure communications, improving wireless network performance, reliability, and adaptability. This paper underscores the pivotal role of IRS technology in the future of wireless networks, presenting new opportunities for secure and efficient communication systems.