Ris-assisted integrated sensing and communication: applications, challenges and usecase scenario

The sixth-generation (6G) speculations are intensifying with the validation of fifth-generation (5G) standardization. Recently introduced as promising enablers of 6G physical platforms, reconfigurable intelligent surfaces (RISs) have demonstrated significant potential to enhance data rates and coverage in next-generation wireless networks. However, despite their scalability and cost-effectiveness, RISs face several critical challenges including hardware imperfections, limited reconfigurability, channel estimation complexity, synchronization issues, and susceptibility to security threats. In this study, a comprehensive examination of the RIS-assisted integrated sensing and communication (ISAC) system is presented. The paper explores various aspects of RIS within ISAC, such as path loss mitigation, energy-efficient techniques, security vulnerabilities, and other existing challenges. Furthermore, key 6G applications are discussed along with the prospective roles of RIS in enhancing ISAC systems. This study also integrates mathematical models to optimize path loss, enhance signal quality, and improve resource allocation. Different use-case scenarios and targeted solutions are analyzed. Based on the modeling results, RIS-assisted NOMA with optimized power allocation is identified as the best-performing approach, offering superior throughput, fairness, and interference resilience compared to existing schemes. This article concludes by outlining the remaining challenges and limitations, providing direction for future research in RIS-assisted ISAC systems.