Pinching-Antenna Systems (PASS): Architecture Designs, Opportunities, and Outlook

Flexible-antenna systems have recently attracted significant research attention due to their potential to intelligently reconfigure wireless channels. However, the current flexible-antenna systems still suffer from fundamental limitations, such as free-space path loss and line-of-sight blockage. This article introduces a novel flexible-antenna system, termed the Pinching-Antenna SyStem (PASS). PASS adopts the dielectric waveguides as the primary transmission medium and radiates signals into free space by flexibly pinching discrete dielectric particles, referred to as pinching antennas, along the waveguide. By combining the strengths of both wireless and wired communication, PASS effectively mitigates inherent wireless limitations while offering high antenna reconfigurability. This article reviews the key features of PASS in comparison with conventional wireless systems, analyzes its main advantages, and discusses potential designs, transmission architectures, and application scenarios. Finally, it outlines promising research directions and open challenges associated with PASS.