Additively Manufactured Semipassive Rotman Lens-Based RIS-Assisted mmID Tag System for Beyond-5G Wireless Networks in Complex Environments

• Published in: IEEE transactions on microwave theory and techniques Vol. 73; no. 1; pp. 650 - 660
• Main Authors: Chen, I-Ting, Lynch, Charles A., Eid, Aline, Hester, Jimmy G. D., Zeng, Kai, Tentzeris, Manos M.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2025; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: 5G mobile communication; Array signal processing; Communication; Inkjet printing; Lenses; Millimeter waves; Oscillators; Pins; Power demand; Radar cross sections; Radio signals; Reconfigurable intelligence surface (RIS); Reconfigurable intelligent surfaces; Rectifiers; Rotman lens; Switches; Wireless networks
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/TMTT.2024.3422386

The authors present a semipassive Rotman lens-based reconfigurable intelligent surface at 28 GHz for beyond-5G applications. One proof-of-concept prototype is inkjet-printed on a thin Rogers substrate using a masking technique followed by etching. The system is characterized by its autonomous mode switching, power consumption, radar cross section (RCS) against angle, and mid-range performance. This millimeter-wave identification (mmID) tag system detects radio frequency (RF) signals with a half-wave rectifier and retransmits signals in selective directions with a 270-kHz amplitude shift keying modulation. This proposed system consumes <inline-formula> <tex-math notation="LaTeX">65~\mu </tex-math></inline-formula>W in the detection mode and <inline-formula> <tex-math notation="LaTeX">143~\mu </tex-math></inline-formula>W in the communication mode, suggesting the potential to be further developed into a fully passive and energy-autonomous system for long-range applications in complex environments. To switch between detection and communication modes, the rectifier oscillates between 6.1 and 9.7 mV, which means that the Rotman lens-based RIS-assisted mmID tag system can operate up to 75 m away for communication mode and 89 m for the detection mode.