A Compact Uniplanar Tri-band Antenna for Wearable Smart Watches

In this paper, a uniplanar tri-band antenna for smart watch applications is presented. Implemented on a FR4 substrate and occupying 38× 38 × 0. 8 mm³, the antenna supports Bluetooth, WiFi 2.4/5. 8 GHz and WiMAX 3. 8 GHz bands. The antenna is composed of an edge tapered, bent monopole element with a capacitively coupled inverted L shorting strip supporting the triband operation in 3:1 VSWR standard and exhibiting positive gain in all bands. The specific absorption rate of the antenna is well within the acceptable limits specified by FCC.

I. Introduction

Recent years have witnessed an increasing demand of wearables such as health and wellness devices, activity trackers and smart watches. These devices communicate with smart phones via Bluetooth or even directly through WiFi making them miniaturized multifunctional computers [1, 2]. Owing to the constraints of small size and close proximity with human body, antennas for a smart watches antenna must have high directivity, low profile and low specific absorption rate (SAR) [3].