Compact-Size Wearable Button Antenna with Low SAR for IOT, Medical and GPS Applications

A compact size wearable button antenna has been designed and presented in this paper. The designed antenna covers widely used 2.4 GHz ISM band for internet of things (IOT) and medical applications. It can also be used for IRNSS-1, S-band (2484 MHz to 2500 MHz) GPS tracking application. The wearable antenna button is designed on a circular piece of low cost FR-4 epoxy substrate with radius 10 mm only. The operating frequency range of the antenna is 2.37 GHz to 2.6 GHz with 230 MHz bandwidth and 2.6 dB peak gain at 2.4 GHz. The usability of the antenna has been examined by on-cloth and on-body performance analyses. The average specific absorption rate (SAR) of the antenna with human body interaction is around 0.1 W/Kg satisfying the guideline of FCC.