Development of flexible durable multi-slotted antenna for wearable applications.

In this study, a multi-slotted antenna is designed and characterized that can be used for wearable applications by utilizing a flexible, durable silicone rubber substrate. Flexible material has become increasingly popular among researchers in recent years for the development of wearable antennas for body area networks (BAN). The flexible device should be small in size so that it can be easily worn on the human body by integrating with wearables for transmitting and receiving signals over a sufficiently long distance. Unlike conventional flexible and semi-flexible substrate, presented work utilize silicon rubber substrate owing the advantages of good thermal stability and good resistance in varying environmental conditions. The designed antenna's surface offers a compact size of 14 × 12 mm with a thickness of 2 mm. The resonance frequency of the designed antenna is optimized at 5.8 GHz with a peak gain of 2.46 dBi. The specific absorption rate (SAR) achieved for the proposed antenna is 1.56 W/kg for 1 g of tissue which fulfills the FCC standard. The design offers radiation efficiency of around 80 % when loaded with hand model over the operational band of 5.5 GHz-6.5 GHz. The bending characteristics of multi-slotted antenna are also analyzed, which offers stable performance as compared to antenna without any bend. Compactness as well as high radiation efficiency have been accomplished that makes the proposed antenna a strong candidate for military applications, medical applications, GPS, RFID, and fitness tracking.