Clevertex - Grado Zero Espace Srl

Foster-Miller also researches on wearable antennas: For the US Army, they integrated data and
communication loop-type antennas into a soldier uniform. They first constructed embedded antenna
prototypes and evaluated loop antenna designs. The project aims at developing a soldier ensemble of
the future, which will monitor individual health, transmit and receive mission-critical information, protect
against numerous weapons, but at the same time it should maintain full antenna performance,
together with the same ergonomic functionality and weight of an existing uniform [79].
Fig. 29 Soldier Uniform of the future [79]
Scientists at the TITV Greiz developed a textile transponder antenna integrated into a label, which can
be attached permanently to textiles. This antenna is flexible, washable and has a good reading range.
It consists of three fabric layers serving different functions. Thus, if a contact point of conductive
threads is desired, the lower and upper layers are responsible for isolation, while the middle layer
incorporates conductive threads in warp and weft direction. For the other case, if no contact point is
desired, the conductive threads are inserted in the lower and upper layer, while the middle layer is
responsible for isolation. However, the conductive threads in this model can also be brought into
contact by a spool structure and therefore can serve as a transponder aerial. As conductive threads,
the research group uses silvered metallised polyamide fibres with a silver layer of approximately 1µm.
In order to achieve a good conductivity they treated these fibres galvanic. They deposited metals such
as gold, platinum, copper, nickel and zinc, as well as the additionally silver on the fibres. However, this
woven layer construction is suitable to be used for electroluminescent light sources which still require
an optical transparent electrode [18, 80, 81, 82, 83, 84].
Another example of a textile transponder was presented by the German company Deister Electronic
GmbH at Avantex 2005, the so-called Textag ® . It is a woven textile structure with an incorporated
aerial thread along with a RFID chip. The aerial thread is a metal wire supplied by the company
Elektrisola Feindraht. The antenna facilitates the storage of production and delivery data directly within
the finished product, enabling each individual process such as production, despatch, shelf time and
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