MEMS-based reconfigurable and flexible antenna for body-centric wearable applications

Abstract

The current study presents an MEMS switche-based frequency reconfigurable antenna for conformal and wearable applications. This is a circular ring-shaped monopole antenna loaded with spokes attached to the circular ring and fed by co-planar waveguide feeding (CPW). The antenna is designed on the flexible Liquid crystal polymer substrate material with 40 × 28 × 0.1 mm3. The reconfigurability of the antenna was achieved by placing RF MEMS SP4 T (ADGM 1304) switches. The antenna has a dual-band with reconfigurability at 2.5 GHz (2.12–2.9 GHz) and 5.4 GHz (4.5–5.8 GHz). The measured results demonstrate the antenna operates at 1.73–3.2 GHz and 4.54–6.3 GHz with resonating frequencies of 2.5 and 5.6 GHz. When placed on the human body, the gain of the antenna variesg from 5.32 to 8.38 dBi for different reconfigurable conditions. SAR analysis results in between 0.15 W/Kg and 1.37 W/Kg for different switching conditions, and the simulation results match with the measurements.