An Improved Gain Antenna Array for Telehealth Monitoring on the Internet of Things Platform

The Internet of Things (IoT) has revolutionized the healthcare sector by connecting at-home patients to doctors. In this article, an improved gain antenna array is proposed to further improve the telehealth monitoring systems on the IoT platform. The proposed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times 2$ </tex-math></inline-formula> antenna array has ultracompact footprints of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.38{\lambda }_{g}^{2}$ </tex-math></inline-formula> and operates at 2.4 and 5.8 GHz bands. The antenna array is implanted inside a multilayer (skin-blood–fat-muscle) canonical phantom model in the simulation environment to validate its performance. Also, the proposed antenna array’s performance is checked in the gel-based skin phantom for experimental verification. The improved performance of the designed antenna array is proved by comparing it with the single antenna. The gain improvement in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times 2$ </tex-math></inline-formula> antenna array configuration is due to the reduced cross-polarization component and increased gain in the boresight direction. However, a single antenna element has comparatively high cross-polarization, leading to low gain in the boresight direction. Due to this, compared to the single antenna element, an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times 2$ </tex-math></inline-formula> antenna array has 10.1 and 4.1 dB improvement in total gain at 2.45 and 5.8 GHz frequency bands, respectively. And improvements in efficiency and front-to-back ratio (FBR) at 2.45 and 5.8 GHz are 10% and 28% and 5.3 and 6.4 dB, respectively. The antenna array is chosen over multiple-input-multiple-output (MIMO) as it provides significant benefits for wireless biotelemetry, including directional beamforming, interference reduction, range extension, and energy efficiency, making it particularly suitable for IoT applications. To date, as per the authors’ literature survey, this is the most compact implantable antenna array with significantly improved gain, bandwidth, efficiency, FBR, and low cross-polarization proposed for telehealth monitoring on the IoT platform.