volume | PIER Journals

Abstract

This paper introduces a hexagon-shaped microstrip fractal antenna over ultra-wideband frequencies for medical purposes when it is positioned in close proximity to the human body. A foam substrate of 2 mm thickness is used with copper as conducting material to investigate the on body performance. The proposed antenna of size 50×38×2 mm³ demonstrated broad frequency coverage from 2.05 to 14.75 GHz and achieved a peak gain of 7.07 dB at 2.5 GHz with maximum return loss of -28.06 dB. The addition of stub has resulted in good impedance matching and is ideal for real-time health tracking, body-centric communication. Its compact size, flexibility, and low-profile nature make it well suited for continuous use in medical environments. A detailed SAR evaluation is performed over a three-layer (Skin, fat, and muscle) phantom equivalent to human tissue for 1 and 10 grams. The on-body, 1 mm and 2 mm away context has been carried out and compared to validate SAR less than the safety threshold as prescribed by IEEE.

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Mr. Prasad A. Pathak

Professor Sanjay Laxmikant Nalbalwar

Professor Abhay E. Wagh

Prof. Jaswantsing L. Rajput