Generalized Pinching-Antenna Systems: A Tutorial on Principles, Design Strategies, and Future Directions
Yanqing Xu, Jingjing Cui, Yongxu Zhu, Zhiguo Ding, Tsung-Hui Chang, Robert Schober, Vincent W. S. Wong, Octavia A. Dobre, George K. Karagiannidis, H. Vincent Poor, Xiaohu You
TL;DR
This work formalizes generalized pinching-antenna systems as a flexible framework that creates on-demand radiating sites along a transmission medium, enabling user-centric coverage and robust LoS links for next-generation networks. It surveys dielectric-waveguide, LCX, and surface-wave realizations, develops fundamental propagation models, and analyzes representative architectures from single to multi-waveguide configurations, including OMA/NOMA and uplink scenarios. Key contributions include closed-form antenna-placement results under LoS conditions, WMMSE/BCD-based optimization for multi-antenna deployments, and learning-based strategies, as well as integrated discussions on ISAC, security, WPT, and near-field capabilities. The paper also outlines open challenges in radiators, EM modeling, robust design, large-scale ELAA, and real-time control, charting a practical path toward deployment of pinching antennas in future wireless networks.
Abstract
Pinching-antenna systems have emerged as a novel and transformative flexible-antenna architecture for next-generation wireless networks. They offer unprecedented flexibility and spatial reconfigurability by enabling dynamic positioning and activation of radiating elements along a signal-guiding medium (e.g., dielectric waveguides), which is not possible with conventional fixed antenna systems. In this paper, we introduce the concept of generalized pinching antenna systems, which retain the core principle of creating localized radiation points on demand, but can be physically realized in a variety of settings. These include implementations based on dielectric waveguides, leaky coaxial cables, surface-wave guiding structures, and other types of media, employing different feeding methods and activation mechanisms (e.g., mechanical, electronic, or hybrid). Despite differences in their physical realizations, they all share the same inherent ability to form, reposition, or deactivate radiation sites as needed, enabling user-centric and dynamic coverage. We first describe the underlying physical mechanisms of representative generalized pinching-antenna realizations and their associated wireless channel models, highlighting their unique propagation and reconfigurability characteristics compared with conventional antennas. Then, we review several representative pinching-antenna system architectures, ranging from single- to multiple-waveguide configurations, and discuss advanced design strategies tailored to these flexible deployments. Furthermore, we examine their integration with emerging wireless technologies to enable synergistic, user-centric solutions. Finally, we identify key open research challenges and outline future directions, charting a pathway toward the practical deployment of generalized pinching antennas in next-generation wireless networks.