A Novel Energy-efficient Health Monitoring System with Electromagnetic- reducing Dual-band Antenna
Tam Nguyen Thanh, Mai Chi Nguyen, Minh Thuy Le, Nguyen Quoc Dinh, Quoc Cuong Nguyen, Kien Nguyen
IEEE Sensors Journal, vol.25, no.10, pp.18201-18212, May, 2025. [pdf document]

<Abstract>

This work presents a novel energy-efficient health monitoring system equipped with an electromagnetic-reducing dual-band antenna. The system features three adaptive measurement modes to save power consumption, Bluetooth low energy (BLE)/Wi-Fi communication, a health status display, and real-time alerts. This article introduces four contributions including: 1) a dual-band wearable antenna operating in the industrial, scientific, and medical (ISM) band; 2) an electromagnetic band gap (EBG) layer that minimizes interaction between the antenna and the human body, reducing specific absorption rate (SAR) values and enhancing performance; 3) a custom-built circuit comprising processing and power management modules; and 4) a dynamic algorithm that adjusts the measurement interval based on the patientfs condition. The EBG layer achieves a significant SAR reduction at 2.45 and 5.8 GHz, lowering values from 3.51 to 0.34 W/kg and 2.4 to 0.43 W/kg, respectively. Unlike traditional systems that rely on fixed monitoring cycles, this device can adaptively adjust its measurement frequency, reducing energy consumption by up to 80.1%. The system was tested and validated across four devices, a gateway, and a Thingsboard platform, achieving an improved signal-to-noise ratio (SNR) of 3?9 dB compared to commercial counterparts and a system latency of under 50 ms.