volume | PIER Journals

Abstract

This study presents a compact patch antenna in the form of a circle, suitable for use in medical and wearable Internet of Things (IoT) devices. The recommended antenna has been proposed to operate on a polyamide material with a dielectric constant of 3.5 and loss tangent of 0.008, at 2.4 GHz and 5.8 GHz bands. The IoT wearable antenna has a specific absorption rate (SAR) obtained at 2.4 GHz that is 0.6 W/kg, while at 5.8 GHz it is 0.8 W/kg for 1 g of body tissue. Both values are significantly below the Federal Communications Commission (FCC) exposure limit, confirming the safe operation of the compact IoT-enabled wearable antenna. The antenna achieves simulated gains of 7.54 dBi and 7.96 dBi with radiation efficiencies of 85.45% and 87.55% at 2.4 GHz and 5.8 GHz, respectively. The proposed system integrates the proposed antenna with an ESP8266 microcontroller, which enables the transmission of vital signs data over an IoT platform. A Modbus protocol and Node-RED platform are utilized for data acquisition, processing, and visualization. This makes it a small, cheap, and reliable solution for IoT-enabled healthcare systems.

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Mr. Rama Krishna Merugumalli

Dr. Subba Rao Chalasani