A Metal Zipper Antenna for Application of Wearable System

The idea of making use of the metal zipper in the clothes to serve as an antenna is proposed and simulations together with the elementary measurements have been carried out. The radiation patterns of the zipper antenna are like that of the monopole antenna to some extent, while the diversity and the freedom of the former one are more suitable for wearable systems. And the diversity in direction can be changed by dragging the handle of the zipper up and down. No matter the zipper is totally closed, opened half, opened a quarter or three quarters or is even totally opened, the antenna can operate with an acceptable performance. Thus, it is naturally reconfigurable in radiation pattern. The feeding point can be located in the bottom of the lower head of the zipper or around it, including the top or the left and the right side of it. Also, the excitation can appear at certain tooth of the zipper. The location variations would bring the changes in the reflection coefficients. Special impedance transforming structure could be designed if certain frequency bands or points are demanded. The measured results indicate reasonable approximations to that of the simulations in the matching and radiation performance for the zipper antenna, which seems to be a promising candidate for wireless wearable electronic equipment and systems.