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Abstract-The emergence of wearable textile systems in recent years exhibited the need for wireless communication tools integratable into garments. In literature, several planar antenna designs based on textile materials have been presented, however, without an adapted feeding structure for wearable applications. An aperture-coupled patch antenna (ACPA) meets this requirement since the rigid coaxial feed is replaced by a microstrip feed line that couples its power into the antenna through an aperture in the ground plane. This letter presents the first ACPA entirely made out of textile material. The result is a highly efficient, fully flexible, and wearable antenna that is integratable into garments.

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®, Shieldit™ 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.

The design and manufacturing of several new textilebased rectangular-ring antennas for body area networks operating in the ISM-band (2.4 GHz-2.4835 GHz) is described. Fleece fabric is applied as antenna substrate, whereas the conducting antenna plane and ground plane are constructed based on a commercially available electrotextile called Flectron. We compare the characteristics of two prototypes that were assembled using different glueing techniques. The influence of bending on the characteristics is investigated. The proposed antennas are the first circularly polarised antennas that cover a bandwidth of more than 190 MHz, using a substrate material with a thickness less than 3 mm. The antennas provide sufficient antenna gain for use in practical wireless links. They allow direct integration into garments.