A PDMS-Based Low-Profile Monopole Antenna for Wearable Applications

A planar monopole antenna using polydimethyl-siloxane (PDMS) as a substrate is presented for on-body wearable applications. Three shorting vias with angular separation of 120 degrees are employed to achieve a low-profile structure with monopole-like radiation pattern. The antenna operates at the Industrial, Scientific and Medical (ISM) band of 5.8 GHz with impedance bandwidth of 4.3% covering frequencies from 5.7 to 5.9 GHz. The proposed antenna is flexible and offers a small size of
$0.53\lambda\times 0.53\lambda\times 0.06\lambda$
at its lowest operating frequency. The experimental validation was carried out in free-space and on-body environment and it demonstrates that the proposed antenna is suitable for on-body wearable applications.