Andrew W. Chu

Body-Worn E-Textile Antennas: The Good, the Low-Mass, and the Conformal

Support of ever increasing applications for wireless data and communications on a body-centric platform requires novel antenna systems that can be integrated with the body-worn environment, while maintaining free-range of movement and minimal mass impact. E-textile antennas show great promise due to their ease of integration with other textile materials, and they are inherently low-mass and flexible relative to conventional antenna materials. Much attention has been given recently to multiple-antenna communication systems due to the increased performance compared to conventional single-antenna systems. For body-centric applications, the low-mass, flexibility, and integration simplicity of e-textile antennas can enable multiple-antenna systems, which otherwise would be precluded by the rigidity and mass of conventional antenna materials. Several examples of this are considered here with e-textile antennas in an array environment. A conventional microstrip array constructed with e-textiles is shown to have robust performance with moderate amounts of bending, similar to that which might be seen with body-worn arrays. In addition to the conventional array, a wideband multiple-antenna system to support a variety of wireless communication protocols, while maintaining polarization diversity and excellent coverage over a majority of the radian sphere is demonstrated.

The radiation pattern of a monopole antenna attached to a conducting box

A system investigation was undertaken to determine the radiation patterns of a monopole antenna mounted on a cubical conducting box over a ground plane. The effects of the location of the monopole and the electrical size of the box were noted as compared to similar patterns measured over a flat ground plane. Experimental results were also compared with numerically predicted values obtained from a method of moments patch code. It was concluded that the location at which a monopole antenna is mounted on a conducting box and the electrical size of the box clearly affect the overall radiation pattern of a monopole antenna. In general, mounting the antenna away from the center of the box will increase the depth of the nulls. >