The use of textile materials to design wearable microstrip patch antennas

So-called "wearable textile systems" are intended to improve the quality of life by enhancing the wearer's functionalities. Garments having the ability to monitor biosignals and communicate with the environment can, for example, provide continuous information about a person's state of health. These data can be valuable medical input, but also in emergency operations such as fire extinguishing, it can be a tool to decide on the operability of the fire fighter. However, wireless communication with the environment requires antennas. When preserving textile properties such as flexibility and comfort is an issue, antennas should be made fully integratable into garments and, thus, manufactured from textile material. This paper shows the feasibility of the use of textile materials in the design of antennas working in the dedicated 2.45 GHz frequency range. We used a commercial electromagnetic field simulator to design microstrip patch antennas fabricated from both conductive (electrotextiles) and nonconductive textile material. For the antenna and the ground plane, readily available electrotextiles were assessed: FlecTron (R), Shieldit (TM) Super and Zelt., while a fleece fabric was used for the antenna substrate. We found that such antenna prototypes had an efficiency of more than 75%, which was comparable to conventional non-textile antennas. This research is an initial step in designing textile antennas and paves the way for a new generation of communicating garments.