Influence of body proximity on the efficiency of a wearable textile patch antenna

The performance of a textile patch antenna designed on a small ground plane for wireless off-body communication applications is assessed when the antenna is brought in close proximity to a human body. The study looks at the effects on the reflection coefficient and efficiency of the antenna as it is placed on the body. Simulated and measured results show that the antenna does not experience any signifiant detuning effects when it is placed on the phantom. The on body 3D radiation patterns were measured along with the efficiency compared to a monopole antenna. It was found that increasing textile ground plane size had a relatively small impact on efficiency. Spacing the antenna away from the body however produced over 75% increase in efficiency and may therefore constitute a robust solution in order to increase the overall efficiency of a wearable communication system. The performance of the antenna was compared to two patch antennas printed on substrates of FR4 and RT/Duroid 5880.