Metamaterial-Based Sensor With Integrated Real-Time Heartbeat and Respiration Monitoring for IoT-Enabled Clinical Applications

Physiological signals such as respiration and heart rate are critical indicators for real-time health monitoring. Although conventional contact-based sensors like electrocardiograms offer high accuracy, they are limited by discomfort, hygiene concerns, and poor long-term usability. Radar-based and wireless RF sensing technologies have emerged as promising non-contact alternatives; however, they face challenges such as environmental interference, line-of-sight constraints, and limited signal selectivity. Additionally, hardware complexity, phase noise, and low signal-to-noise ratio hinder performance in dynamic environments. To address these limitations, this study proposes a novel physiological sensing system based on spoof surface plasmonic (SSP) metamaterial structures. These SSP-based sensors offer a low-profile design, material compatibility, and strong surface wave confinement, along with radiative capabilities for short-range wireless communication. By integrating SSP waveguides with radiative elements, the system enables passive, indirect-contact, and reliable detection of vital signs, providing improved robustness over traditional radar-based solutions. Furthermore, the system supports remote sensing and IoT-based connectivity, enabling seamless integration into healthcare monitoring networks. Experimental validation confirms the system’s potential for unobtrusive health monitoring in clinical settings. This work lays the groundwork for metamaterial-assisted sensing systems in next-generation biomedical applications.