A Survey on STAR-RIS Enabled Joint Communications and Sensing: Fundamentals, Recent Advances and Research Challenges
Wali Ullah Khan, Chandan Kumar Sheemar, Syed Tariq Shah, Manzoor Ahmed, Symeon Chatzinotas
TL;DR
This paper surveys STAR-RIS-enabled joint communications and sensing (JCAS) as a core 6G capability, highlighting how full-space wave control via STAR-RIS can mitigate the traditional trade-offs between data rate and sensing accuracy. It provides a unified framework covering fundamentals, STAR-RIS signal models, operating protocols, architectures (passive/active), and a broad spectrum of applications, then delves into recent advances in architectural design, waveform strategies, security/privacy, energy efficiency, NOMA/RSMA interfaces, and mobility/UAV contexts. The work identifies key open challenges—CSI acquisition, hardware coupling, control overhead, near-field effects, and cross-layer integration—and outlines forward-looking research directions including hardware-aware modeling, low-complexity real-time optimization, mobility-predictive control, and prototyping. Overall, the survey demonstrates STAR-RIS-enabled JCAS as a viable pathway to perceptive, adaptive, and efficient 6G networks, with substantial implications for V2X, IoT, indoor localization, and aerial networks.
Abstract
The joint communications and sensing (JCAS) paradigm is envisioned as a core capability of sixth-generation (6G) wireless networks, enabling the integration of data communication and environmental sensing within a unified system. By reusing spectrum, waveforms, and hardware resources, JCAS improves spectral efficiency, reduces system complexity, and hardware cost, while enabling new use cases. Nevertheless, the realization of JCAS is hindered by inherent trade-offs between communication and sensing objectives, limited controllability of wireless propagation, and stringent hardware and design constraints. Simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RIS) have recently emerged as a promising technology to address these challenges by enabling full-space programmable manipulation of electromagnetic waves. This survey provides a systematic and in-depth review of STAR-RIS-enabled JCAS systems. Specifically, we first introduce the fundamental principles of JCAS and STAR-RIS. We then classify and review the state-of-the-art research on STAR-RIS-assisted JCAS from multiple perspectives, encompassing system architectures, waveform and beamforming design, resource allocation, optimization frameworks, and learning-based control. Finally, we identify key open challenges that remain unsolved and outline promising future research directions toward intelligent, flexible, and perceptive 6G wireless networks.