Design and SAR Analysis of AMC-Based Fabric Antenna for Body-Centric Communication
Usman Ali, Sadiq Ullah, Abdul Basir, Babar Kamal, Ladislau Matekovits, Hyoungsuk Yoo
Abstract
This study designed and analyzed an artificial magnetic conductor (AMC)-based fabric antenna for body-centric communication. The antenna was made of felt and had a loss tangent of 0.044 and relative permittivity of 1.3. The proposed antenna was built to function in the frequency band centered at 2.45 GHz, widely used in wireless communication devices. The antenna’s performance was evaluated using the electromagnetic simulation software CST MWS. A 50 Ω SubMiniature version connector was used to excite the proposed antenna. A 2 × 2 AMC array was integrated into the antenna below it to improve its performance in terms of radiation efficiency, gain, and backward radiation reduction. The antenna and AMC array were fabricated on flexible fabric substrates. The total volume of the AMC-integrated antenna is 0.55λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.55λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.016λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> . It was demonstrated that adding an AMC array enhanced the radiation properties of the antenna and significantly decreased its back lobes. The on- and off-body maximum gains of the AMC-integrated antenna are (≥ 4.11 dBi) and 5.23 dBi, respectively. Furthermore, employing the AMC array, a significant reduction in the specific absorption rate value, which is (≤ 0.43 W/kg) for human body tissue chest/back and (≤ 0.75 W/kg) for human body tissue arm, was obtained, ensuring safety for human use. The simulated and measured results were in agreement. The tested on- and off-body radiation efficiencies in the frequency band centered at 2.45 GHz is (>67%) and (>83%), respectively. The proposed antenna can potentially be used in various applications such as healthcare monitoring, wearable electronics, and Internet of Things (IoT) systems, where reliable and efficient communication is required in a body-centric environment.