Polarization Diversity Antennas for Body Area Network

Abstract

A design of inverted-J shape wearable antennas for wireless local area network (WLAN) application is introduced in this project. The antenna aims to implement on hearing aid. The dual antennas are implemented orthogonally, which allow the function of switching, selecting and combing the signals, achieving polarization diversity. The antenna consists of a couple of inverted-F antennas placed vertically and laterally, with materials copper, and FR4 substrate behind. The overall dimension of the antennas are 36mm x 32mm. The shape achieved is similar to an inverted-J, which allow user to wear on ears. Two independent coaxial feed in length 80mm are used. The wearable antennas are designed for 2.45GHz. The return loss, radiation patterns and peak gain between simulation and measurement will be presented and compared. The return loss and insertion loss between the two feed will be shown. On human body performances of the antenna are also investigated by measurement. The final results showed that the antenna achieved polarization diversity and is-available for the body area network application.