Design and Analysis of a High Isolation Dual Element MIMO Antenna for Wireless Body Area Network Application

Incorporating multiple-input multiple-output (MIMO) antenna systems into wearable health monitoring platforms significantly enhances reliability and efficiency of wireless data communication. When MIMO technology is integrated within biosensing devices, it improves signal robustness and system functionality, allowing for more accurate and uninterrupted real-time monitoring of physiological parameters. This study presents a dual-element MIMO antenna with an equilateral triangular shape patch, designed for excellent port-to-port isolation, manufactured on a textile substrate, and utilizing the 2.45 GHz ISM frequency range. With compact dimensions of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.51 \lambda_{0} \times 0.44 \lambda_{0}$</tex> (where <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\lambda_{0}$</tex> is the electromagnetic wavelength at 2.4 GHz in vacuum), this design is pertinent for synchronised integration into WBAN (Wireless Body Area Network) scenarios. The proposed framework with a multiport antenna incorporates a decoupling structure that improves isolation by approximately 57 % and achieves a peak gain of 3.71 dBi. The diversity metrics of the MIMO antenna, including an Envelope Correlation Coefficient (ECC) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\leq 0.01$</tex>, Diversity Gain (DG) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\geq 9.98 ~\text{dB}$</tex>, Total Active Reflection Coefficient (TARC) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\leq-10 ~\text{dB}$</tex>, and Channel Capacity Loss (CCL) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\leq 0.4 \text{bit} / \mathrm{s} / \text{Hz}$</tex>, featuring a specific absorption rate (SAR) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1.07 ~\mathrm{W} / \text{kg}$</tex>, validate the viability of the design for wearable health monitoring deployment.