Compact Dual-band Meander-line Antenna Backed by AMC for High-gain IoT Applications

In this paper, a compact dual-band meander line antenna backed by a metamaterial-based artificial magnetic conductor (AMC) is presented for IoT and wearable biomedical applications such as WBAN and health monitoring systems. The proposed antenna operates at 2.45 and 5.0 GHz Wi-Fi/WLAN bands, which are commonly used ISM bands for IoT and wearable devices. The dual resonant behavior in a highly compact structure is designed with the help of a folded meander-line radiating structure, which is backed by an AMC reflector behind the antenna to enhance broadside gain and minimize the radiation toward the human body to reduce Specific absorption rate (SAR). The deep learning-based surrogate modeling and inverse optimization framework is used to design the AMC unit cell, which efficiently predicts reflection phase i.e. 0o phase at both the operating frequencies. The use of AMC backing ensures the enhancement of the gain of the proposed low-profile antenna of approximately 3.4 dB at 2.45 GHz and 3.1 dB at 5.0 GHz. The equivalent circuit modeling and parametric analysis of the antenna and AMC unit cell are analyzed to get further insights into the design. Full wave simulation of AMC-backed antenna in the presence of Phantom confirms the impedance matching at both the operational bands and directional radiation patterns with improved front-to-back ratio. The proposed AMC-backed antenna design confirms the potential of a combination of deep learning-driven AMC unit cell design in the enhancement of gain and reduction in SAR for IoT and Wireless Body Area Network (WBAN) applications.