A dual-band Quasi-Yagi wearable antenna with high directivity

A Quasi-Yagi wearable antenna is presented in this paper for dual-band operations at WiFi bands with high individual directivities. The proposed antenna structure consists of a single-stage director, two arms of driven elements and a concave parabolic reflector. The measurement results show a directivity of 6.8 dBi with 12% bandwidth at 2.45 GHz and a directivity of 5.3 dBi with 10% bandwidth at 5 GHz, respectively. Both the lower band and the higher band can be tuned by changing the length of the two driven arms with stable radiation patterns. The size of this dual-band antenna is only 55 mm × 48 mm × 0.25 mm. The proposed antenna is promising for the applications of both wireless power transfer and wireless communication for wearable devices.